Automotive engine oil pan 1, defects that appear The product is an essential part of the car engine, the working environment is harsh, and it is required not to leak oil. We mainly encounter the sensor hole air holes in the production of this product that can not meet the requirements, large plane local air holes into pepper powder, it is difficult to lift. 2, the reasons for the generation 1) Oil sump is a deep cavity part, aluminum liquid from the water mouth to the water tail, the process is long, easy to produce cold material. And the sensing air hole is an isolated part, which is not conducive to the discharge of cold material. 2) The principle of product die-casting release agent is manual spraying, the amount of spraying changes every time, and there are more unstable factors, causing the product to be easily deformed. 3) Bad exhaust. 3, Solution 1) Open a slag collection bag in the sensor part to facilitate the discharge of cold material in this part. 2) Use ABB robots to ensure stable and fast spraying. 3) Open an exhaust block on the mold to get the best exhaust effect. Thermostat housing 1, Defects that occur The product needs not to show water under high temperatures and pressure, so the sealing groove of the product is required to be very strict. Product sealing slot requirements do not allow air holes, such as in production, the end of the product often appear pepper-like air holes, will cause the product scrap; and the proportion of air leakage caused by more. 2, the reasons for the generation 1) complex structure of the product, more tabs in the middle, the aluminum liquid is not smooth in the flow, at the end of the product is easy to produce rolled gas. 2) The wall thickness of the product varies too much, the smallest place is only 4 mm, but the thickest place can reach 30 mm, and it is easy to produce shrinkage and shrinkage holes in the wall thickness. 3) There is an 85 mm long sliding block on the product, which is easy to pull on and crack the product, causing air leakage. 3, Improvement measures 1) Add a vacuum exhaust device to the mold to reduce the amount of gas in the mold cavity. 2) Open a partial extrusion pin at the product wall thickness to reduce the product shrinkage and shrinkage hole. 3) Make program changes to the machine, set core extraction spraying, and spray lubrication to the oblique extraction core to reduce the phenomenon of strain and cracking. Aluminum alloy base 1, defects The problem of casting inlet buckling, buckling crack, and deformation after cooling occurs during the trial production of the product. 2, Causes of occurrence 1) Casting heat sink with the thin and narrow wall, in order to cast water tail heat sink forming good and take high speed and high-pressure molding, resulting in a large impact on the inlet port buckling die buckling crack. 2) The casting is too long, uneven wall thickness, different crystallization strength of each part, and the shrinkage in cooling have different differences causing distortion and deformation. 3, improvement measures 1) Do surface cloaking treatment at the inlet of the mold to improve the buckling mold. 2) Take vacuum die-casting, not to reduce the inner gate speed and improve the internal quality when reducing the injection speed and pressure, so as to reduce the impact on the inlet port during the injection and improve the buckling mold. 3) Adopt cooling without water spout to reduce the deformation by pulling the casting during cooling. 4) Pre-align the product in the condition of semi-cooling of the casting, when the internal stress of the product is not completely released. Gear chamber 1, Defective problem Air leakage was found during product air inspection. 2, Cause Analysis The casting structure is complex, and in order to achieve a good appearance and required strength, the filling speed is up to about 60m/s and the specific pressure is more than 820kg/cm2. Therefore, a great impact on the part shown, so that the product surface burns, sticky aluminum; at the same time, due to the large difference in wall thickness of the part, the cooling rate is not the same and will lead to shrinkage, shrinkage crack, and these defects will lead to air leakage in the product in the gas inspection. 3, solution 1) Adopt point cooling method for die cooling in the corresponding part, which increases the local cooling effect; adopt local extrusion pin process to solve the problem of shrinkage. 2) Do surface cloaking treatment at the inlet of the mold to improve the buckling die and solve the burn. The gas station connection body 1, defect problem Casting both sides of the core extraction cavity buckling injury and lamination, the fixed mold forming surface of the two fixed columns has water lines or cold separation. 2, cause analysis 1) Due to the thin and long cores on both sides, the casting is wrapped by aluminum liquid, the temperature rises quickly, causing the cores to adhere to the inner cavity of the casting, and strains when taking off the mold. 2) After closing the mold, the core and the mold with a gap, resulting in feeding, forming a flying edge, after opening the mold, the core extraction, the flying edge can not be normal off, was caught in the mold, after closing the mold, the flying edge with the core inserted, the next filling, aluminum liquid in the flying edge on both sides of the molding, forming a sandwich. 3) The two fixed pillars on the molding surface of the fixed mold extend into the mold 35 mm, and are slender, with cooling water inside the mold, the top of the pillar is closer to the cooling water channel, after opening the mold, the pillar position cools down faster, and when spraying, the mold release agent is easy to remain because of the small space in the cavity of the pillar. 3, Solution 1) Install additional cooling points inside the extractor core on both sides of the mold to take away the heat from the end properly. 2) Polish the surface of the extractor core to stick to aluminum and cloak it to prevent the flying edge from sticking. Enable deceleration, deceleration position 525 mm to prevent flying edge. 3) Open 1/3 of the cooling water at the two pillars after normal, reduce the mold temperature appropriately, and blow out the residual mold release agent in the inner cavity after spraying in the fixed mold.

Factors affecting the size of die castings are broadly the following. 1, molding compression is caused by the size of the error. Molding shrinkage is the main factor affecting the size of die castings. Because molding compression is a complex process, so the shrinkage rate has a wide range of choices. According to the external shape of the die casting and structural characteristics, respectively, select the size of each part of the appropriate molding shrinkage and determine the size of the molding, is to ensure that the die casting size accuracy of the key issues. 2, the manufacturing error of molding parts. 2.1, the molding parts of the insert, mold processing datum, and the impact of processing technology. 2.2, machining errors of molded parts. 2.3, assembly errors of molded parts. 2.4, the error caused by the slope of the molded parts of the mold. 3, the influence of fluctuations in molding shrinkage during die-casting. 3.1, the influence of die-casting molding process parameters, such as press injection ratio pressure and internal gate speed. 3.2, the effect of mold temperature. 3.3, the effect of the temperature of the die casting when the mold is removed. Die castings in the shrinkage process, broadly divided into the following three stages. a, liquid shrinkage, after die casting, still in the liquid metal liquid temperature reduction caused by shrinkage; b, solidification shrinkage, in the cooling and solidification process, the metal liquid from the liquid to solid crystallization stage shrinkage; c, solid shrinkage, metal completely solidified when the crystallization is completed stage and out of the mold body shrinkage. In die casting, because the superheat temperature of the metal liquid is not high, so the volume shrinkage in the liquid shrinkage stage is not large; shrinkage in the solidification stage, although larger, but is completed in the mold forming parts, and therefore by the molding parts, especially the core of the resistance limit. When the die-casting die temperature decreases and can reach the temperature of the mold, die castings from the mold body, only after the free shrinkage state, that is, the solid-state shrinkage stage. This shrinkage process has continued until the die casting reaches room temperature before the basic end. Therefore, it can be said that the temperature of the mold of the final shrinkage of the die casting plays an important role in determining the amount. 4, the error caused by the phase time movement of the structural parts. 4.1, mold closing errors. 4.2, the movement error of the side-drawing core and the movable core. 4.3, the error caused by the precision of the die-casting machine and the instability of the process performance. 5, punching error. 5.1, molding parts by the impact of pressure injection deformation caused by the error. 5.2, forming parts surface by the metal liquid or impurity erosion generated by the error. 5.3, subject to pressure injection stamping, template, or forming parts to produce elastic deformation or plastic deformation and the formation of forming part of the size error.

1, structural process analysis of die casting 1.1 The reasonable choice of materials used in die casting. Aluminum alloy because of its good die-casting performance, specific strength, and specific stiffness is high, high and low-temperature mechanical properties are also good, its surface has a dense oxide film, and certain corrosion resistance and in the production of die castings are used in large quantities, widely. 1.2 The minimum wall thickness of the die casting is 3mm, and the minimum wall thickness is also by the process requirements, and the 3mm*54mm rib on the two long sides, 8mm*4mm rectangular hole, R4mm flange, etc. are also by the requirements of the die casting process. 1.3 Because of the strong affinity between aluminum alloy and iron at high temperatures, it is easy to bond with the pressure chamber, and the die-casting mold design should use a cold chamber die-casting machine as far as possible. 2, the choice of parting surface According to the middle shell for the long frame hollow parts, both sides of the long side have different side convex, step, small rectangular hole structure characteristics. The die casting parting surface of this die casting, except for the horizontal parting between the moving die and the fixed die, is chosen in the upper face of the shell, and the forming of both long sides needs to adopt the lateral parting mold structure form (i.e. the form of lateral core extraction of the inclined pin slider). 3, the determination of the pouring system Due to the thin wall thickness of the four sides of the intermediate shell and the difference between the plant and width dimensions, to prevent cold separation and ensure the thermal balance of the mold, the pouring system uses side gates. The molten alloy is pressed in simultaneously from both ends of the long side of the casting, and a larger overflow slot is set at the part where the metal liquid meets or is likely to produce eddy currents. A larger overflow slot can be set both exhaust role and can set slag and conducive to the thermal balance of the mold. 4, the choice of die-casting machine The middle shell is no insert die-casting, can choose horizontal cold room die-casting machine, according to the actual production of enterprises to choose the appropriate die-casting machine, to meet the actual production requirements. 5, die-casting mold forming parts working size calculation and determination By die-casting alloy comprehensive shrinkage rate list data can be seen: aluminum alloy shrinkage rate in the free shrinkage rate of 0.50%-0.75%; hindered shrinkage rate of 0.40%-0.65%. After separate analysis and calculation, it is determined. 6, die-casting process protocol The process protocol is mainly to determine the process parameters of die-casting production. Die-casting production process parameters mainly include die-casting with new, old material reasonable ratio (old material is impossible to abandon, new, old material unreasonable ratio will affect the material performance and shrinkage rate), determine the die-casting production process protocol, equipment, the correct use of paint (because it has the role of improving the working conditions of the mold, improve molding conditions, improve the quality of castings and extend the life of the mold and essential), etc. 7, die-casting mold assembly design There are two structural options in the design of die assembly. Program one: die-casting forming castings, the shape of the inner cavity mold forming part are designed into the form of the overall structure; program two: forming castings, the shape of the mold work parts are designed into the set, set block set combination of structural form. After analysis and comparison, although program one uses less material, good strength, short processing cycle, but the mold manufacturing accuracy is difficult to ensure that the mold damage and wear are not easy to repair. While the second option increases the use of alloy steel, the processing cycle is extended, but the precision of the working parts of the mold is easy to ensure, and the size adjustment of the working parts of the mold and the wear and damage formed after a certain period of production is also convenient to repair and replace. In the assembly structure of the mold, the fixed mold insert and the fixed mold insert of the fixed mold part are set into the fixed mold plate in the form of grouping. For the moving side, the moving die insert and the moving die insert are inserted into the moving template in a group. The die plate is made of medium carbon steel. The working parts are made of hot work die steel for die casting, the strength, and processing accuracy of the die can be guaranteed, and the adjustment of each forming size is also convenient. Because the hollow shell of die casting has long sides of rectangular holes, flanges, convex tendons, and other structures respectively. So both sides need to use different slider structure forming, tilt pin core parting, wedge tight block locking lateral forming form. Considering the thin wall thickness around the middle shell, and the size of the overflow groove has been enlarged, so pushrods are set on the overflow groove and the cross sprue, and 8 rectangular sheet pushrods are set on both sides of the long side of the die casting to ensure the smooth and synchronous launch of the overflow groove, cross sprue and die casting. The mold is reset by the reset rod to push the pushrod fixed plate to reset.

In the ordinary casting process, the initial crystal grows in the way of dendrites, and when the solid phase rate reaches about 20% the dendrites form a continuous network skeleton and lose macroscopic mobility. If strong stimulation is applied during the solidification of metal, the dendritic network skeleton easily formed during ordinary casting will be broken into dispersed particles suspended in the remaining liquid phase, and this alloy prepared by stirring is generally called a non-dendritic semi-solid alloy. This semi-solid alloy still has good fluidity when the solid phase rate reaches 50%-60% and can be formed using conventional forming processes such as pressure casting, extrusion casting, continuous casting, vacuum casting, etc. to achieve metal forming. 1, Preparation of semi-solid alloys To realize the semi-solid die-casting, first of all, we must prepare the semi-solid alloy slurry with the non-dendritic organization. The current preparation methods of semi-solid alloy slurry mainly include mechanical stirring method, electromagnetic stirring method, strain-induced melting activation method, jet casting method, semi-solid isothermal heat treatment method, near liquid phase line casting method, and chemical grain refinement method, etc. 2, The application of semi-solid die-casting It is expected that the main market for semi-solid die-casting is the automobile industry for quite a long period of time, and aluminum alloy and magnesium alloy are the main materials for semi-solid die-casting in the automobile manufacturing industry. Through the die-casting process real-time control research, so that the whole die-casting process is under dynamic monitoring, improve the performance of die-casting, reduce die-casting scrap, and can make an ordinary die-casting machine for semi-solid metal die-casting forming. Automotive wheel hubs are mostly made of steel, to reduce the quality of the car now increasingly use aluminum alloy, its forming process is mainly low-pressure casting, but low-pressure casting has a high scrap rate, low productivity shortcomings. The use of semi-solid die-casting forming, can customer service the above disadvantages, and improve the strength of the product, reduce the quality. The semi-solid metal forming process has various characteristics and advantages that traditional processing and forming technology does not have, in the past decade, the rapid development of semi-solid forming technology, has gradually become a new field of competition, known as a new generation of emerging metal forming technology.

1, Thermal fatigue cracking Die casting production, die repeatedly by the role of cold and heat, forming surface and its internal deformation, mutual involvement and repeated cycles of thermal stress, resulting in structural damage and loss of toughness, triggering the emergence of micro-cracking, and continue to expand, once the crack expands, there is molten metal liquid extrusion, coupled with repeated mechanical forces are to accelerate the expansion of the crack. Therefore, in actual production, most of the mold failure is thermal fatigue cracking failure. 2, Brittle cracking Under the action of pressure injection force, the mold will sprout cracks at the weakest point, especially the mold forming surface scribing traces or electric machining traces are not polished, or forming at the angle of inclination will be the first to appear fine cracks, when the grain boundary exists brittle phase or grain coarse, that is easy to fracture. When the brittle fracture is present in the grain boundary or the grain is coarse, it will be easy to fracture. The expansion of the crack is very fast. The brittle failure of the mold is a very dangerous factor, the mold material's plastic toughness is the most important mechanical property corresponding to this phenomenon. 3, Dissolution corrosion Commonly used die casting alloys are zinc alloys, aluminum alloys, magnesium alloys, and copper alloys, but also pure aluminum die casting, Zn, Al, Mg is more active metal elements, they have a good affinity with the mold material, which is due to the combined effect of mechanical and chemical corrosion. Especially Al is easy to bite the mold, molten aluminum alloy shot into the cavity at high speed, resulting in mechanical corrosion of the cavity surface, at the same time, the metal aluminum and mold material to generate brittle iron-aluminum compounds, become a new source of hot crack sprouting, in addition, aluminum filling to the crack and crack wall mechanical action, and superposition with the thermal stress, intensify the tensile stress at the tip of the crack, thus accelerating the expansion of the crack. When the mold hardness is higher, the corrosion resistance is better, and if there are soft spots on the forming surface, it is not good for corrosion resistance. However, in actual production, the dissolution corrosion is only the local place of the mold, generally, the part where the inner gate is directly flushed (core, cavity) is prone to dissolution corrosion, as well as the hardness is soft where the aluminum alloy is prone to sticky mold. Improve the high-temperature strength and chemical stability of the material is conducive to enhance the corrosion resistance of the material.

1, Adjustment content After the die casting mold manufacturing is completed, it should be adjusted after the mold test to choose the correct die casting conditions in order to achieve stable die casting of qualified castings. Before the mold test, mold test personnel should do die casting with alloy materials for inspection, to understand the characteristics of alloy materials and die casting characteristics; should also understand the mold structure, die casting machine performance, die casting conditions, and operating methods. The correct choice of die casting formation conditions is the key to die test adjustment. Often encountered even if the mold design and manufacturing are correct, due to improper selection of die casting forming conditions, the same can not press qualified castings. On the contrary, in some cases, can be used to adjust the die casting forming conditions, to overcome the shortcomings of the mold, press out the qualified castings. For this reason, mold test personnel must be familiar with the role of the die casting molding conditions and the relationship between, mold action principles, in order to correctly select and reasonably adjust the die casting molding conditions. Die casting molding conditions of the adjustment of the following points. 1) Material melting temperature, die temperature, and solution temperature during die casting. 2) The injection pressure of the die casting machine, clamping force, mold opening force, and the required injection ratio pressure, injection speed size, etc. according to the condition of the parts. 3) The condition of the die-cast product should be trimmed in order to get a perfect part. 2, Trial mold process Mold test is the last part of the mold manufacturing, is in the die casting machine on the die casting mold molding effect of the field inspection process. The purpose of the mold test is not only to test the mold design and manufacturing but also to seek the best molding process conditions for formal production. The process of mold trial is divided into three stages: mold loading, mold trial, and adjustment. 1) Mold assembly Mold assembly includes pre-inspection, mold installation, and adjustment, etc. 2) Mold test The main contents of mold trial are as follows: ① mold preheating ② the pouring temperature ③ select the ratio of pressure injection ④ to select the speed of pressure injection ⑤ to determine the filling time 3, Adjustment method Possible defects, causes, and adjustment methods in die casting mold trial

Parts processing inspection is the fundamental guarantee and basis of parts accuracy and mold product quality, mold parts inspection content and inspection means depending on different production conditions and production scale and different. Because the mold processing belongs to the single-piece production, processing processes, parts surface complex, its quality inspection, and conventional testing are slightly different. At the same time for the mold cavity hardness, corrosion resistance and ornamental processing requirements are difficult to achieve through the general testing methods, only through certain processing methods and process measures to ensure. Sometimes the test results of mold parts can not be evaluated by qualified or not, such as the cavity surface polishing usually indicates the quality of polishing. This is the difference between mold parts testing and ordinary parts testing. Mold parts inspection content Mold parts inspection content is mainly geometric inspection, including size tolerance, shape tolerance, position tolerance, surface roughness and threaded core, cavity tolerance, etc. Dimensional tolerance requirements are to ensure the accuracy of the size of the parts, with dimensional tolerance requirements, are to ensure the interchangeability of the parts, the accuracy of the fit of the motion vice, fit clearance, and deviation. There are two kinds of dimensional tolerances: linear dimensional tolerance and angular taper tolerance. Shape tolerance requirements are to ensure the accuracy and working performance of the mold. Shape tolerance is for a single element, including straightness, flatness, roundness, cylindricity, line contour, and surface contour, etc. Position tolerance is for the associated elements, including parallelism, perpendicularity, inclination, coaxial, position, and symmetry, etc. Surface roughness is an indicator that characterizes the microscopic morphological error of the workpiece surface. Thread inspection includes single-content inspection (such as pitch, tooth angle, mid-diameter, etc.) and comprehensive inspection. 1. Mold plate parts This type of parts mainly affects the closing accuracy and movement accuracy of the mold and is also an important reference surface in the process of processing and assembly, which needs to focus on the inspection of the surface roughness of the upper and lower plane, parallelism, flatness, perpendicularity with the side, cylindricity of the hole system, perpendicularity, hole size, and hole spacing size. 2. Cavity type parts These parts are directly related to the dimensional accuracy of the plastic parts, which is the core part of the mold processing but also needs to focus on the content of the inspection. The inspection of cavity parts includes almost all the contents of dimensional tolerance, shape tolerance, position tolerance, surface roughness and tolerance of threaded core and cavity, etc. At the same time, there are also requirements of release slope and surface quality inspection, such as the evaluation of polishing quality and the judgment of whether the plating is off. 3. Structural parts These parts have the function of guidance and movement, such as guide pillars, guide bushings, sliders, etc., the surface quality requirements are high. Guide pillar inspection indicators are the coaxial, cylindricity, radial dimensions of each step axis section. The guide sleeve is mainly to detect the coaxial, cylindricity, and radial dimensions of its internal and external cylindrical surface. The slider has high accuracy requirements for the parallelism, flatness, and angle of the locking bevel of the sliding fit surface. The tie rod mainly detects the consistency of the axial functional dimensions, and the pressure plate mainly detects the parallelism, perpendicularity, and consistency of the functional dimensions. For push rods, reset rods, and other outsourced parts mainly from the incoming channels to ensure quality, you can test the radial dimension, hardness. 4. Standard parts class parts The inspection of standard parts class parts needs special equipment, which is difficult to carry out in general enterprises, but the premature fatigue of screws and premature failure of reset springs may cause damage to the mold. So we should use some products from famous enterprises with good quality and high reputation to avoid similar problems.

In addition to the quality of die casting is affected by a variety of process factors, the structural design of its parts is also a very important factor, its structural rationality and process adaptability determine whether the subsequent work can be carried out smoothly. Die-casting production technology problems encountered, such as the selection of the parting surface, the design of the sprue, the layout of the launch mechanism, the mastery of the shrinkage law, the guarantee of precision, the type and degree of defects are related to the die-casting process of the die casting itself. 1, Die-casting Process Requirements For Die Casting Structure. Design die casting in addition to structure, shape, and other aspects have certain requirements, but also should make die casting adapt to the die-casting process. Die casting structure design directly affects the die casting mold structure design and manufacturing of the degree of difficulty, productivity and mold life, and many other aspects, so the design of die casting must emphasize the cooperation between the designer and die casting process personnel, so that die casting in the die casting process may appear many unfavorable factors to be considered in advance and to be excluded. If the designer is also familiar with the die-casting process, then the design of the structure of the die casting is usually more reasonable. The requirements of the die-casting process for die-casting structure design are as follows. Requirements To be able to easily remove the die casting from the mold; To try to eliminate the side concave, deep cavity; To minimize the core extraction part; To eliminate the crossed parts of the mold core; The wall thickness should be uniform; To eliminate sharp corners. Description All the obstacles that are not conducive to the die casting out of the mold should try to eliminate in advance when designing the die casting; Internal side concavities and deep cavities are the biggest obstacles to mold release. When it cannot be avoided, it should also facilitate the extraction of cores to ensure that the die casting can be removed from the die casting mold smoothly; Each additional core extraction makes the mold more complex and increases the risk of mold failure; When the core crosses, not only make the mold structure complex but also prone to failure; When the wall thickness is not uniform, the die casting will have shrinkage deformation due to the different solidification rates and will produce internal shrinkage and pores, and other defects in the thick part; Reduce casting stress. 1.1 die casting should simplify the mold structure, extend the life of the mold. 1) design die castings as far as possible to make the parting surface simple; 2) to avoid partial thinning of the mold, to ensure that the mold has sufficient strength and rigidity; 3) to prevent the die casting deformation. 2, The Structure Of The Die Casting Process Elements The basic structural process elements of die casting include wall thickness, ribs, casting holes, casting rounding, release slope, thread, gear, slot gap, rivet head, convex pattern, mesh, text, logo, pattern, embedded casting, etc. 2.1 Wall thickness and rib design Die casting reasonable wall thickness depends on the specific structure of the casting, alloy properties and die-casting process, and many other factors. The practice has proved that, as a rule, the mechanical properties of die casting with the increase in wall thickness and decrease. Thin-walled castings than thick-walled castings have higher tensile strength and denseness, thin-walled die casting wears resistance is also good. Die castings with the increase in wall thickness, its internal porosity, and loosening and other defects also increased, so in order to ensure that die castings have sufficient strength and stiffness of the premise, a reasonable wall thickness should be designed into a thin wall and uniform wall thickness, otherwise, it will lead to the uneven internal organization of die castings, but also to the implementation of the die-casting process increases the difficulties. In the usual process conditions, the wall thickness of the die casting should not exceed 4.5mm, the maximum wall thickness and minimum wall thickness ratio should not be greater than 3:1. The thick wall of the die casting, in order to avoid defects such as sparse, should be thinned wall thickness and additional reinforcement ribs.

With the progression of science and technology, the market competition is becoming more and more fierce, and the product renewal cycle is getting shorter and shorter, therefore, shortening the development cycle of new products and reducing the development cost are the urgent problems faced by every manufacturer, and the requirement of rapid mold manufacturing comes into being. Rapid mold making technology includes the traditional rapid mold making technology, such as low melting point alloy mold, electroforming mold, etc., and Rapid Prototyping (RP) for rapid tooling. Principles and characteristics of rapid prototyping technology There are many specific process methods of rapid prototyping technology, but the basic principle is the same, that is, the material addition method is the basic method to rapidly transform a 3D CAD model into a 3D solid prototype composed of specific substances. Firstly, a 3D CAD model is obtained in the CAD modeling system, or the shape and size of the entity are measured by measuring instruments and transformed into a CAD model, then the model data is processed and discretized in a plane layering along a certain direction, and then the embryo is processed by a special CAM system for layering forming and stacking into a prototype. Rapid prototyping technology opens up the way to rapidly manufacture various parts without any tool and provides a new manufacturing means for parts or models that cannot or are difficult to manufacture by conventional methods. It has shown good application prospects in the fields of aerospace, automotive design, light industrial product design, human organ manufacturing, architectural design, mold design, and manufacturing. In summary, rapid forming technology has the following application characteristics. 1, because rapid forming technology uses the mechanism of transforming three-dimensional shapes into two-dimensional planar layered manufacturing, it is insensitive to the complexity of the geometric structure of the workpiece, thus it can manufacture complex parts, fully reflect the design details, and directly manufacture composite parts. 2, rapid manufacture of molds ①Can manufacture metal molds from die castings with the help of electroforming, arc spraying, and other technologies. ②The rapid manufacturing prototype as a vanishing mold also can be used for batch manufacturing of vanishing molds for precision casting by prototype turning and manufacturing master molds. ③Fast manufacturing of high precision complex master molds for further casting of metal parts. ④Make graphite electrode by prototype, and then process the mold cavity from graphite electrode. ⑤ Direct machining of ceramic cavities for precision casting. 3, application in new product development, through the prototype physical model, the designer can quickly assess the feasibility of a design and fully express its conception. ①Shape design. Although CAD modeling systems can view the design model of a product from all directions, they are in no way as intuitive and visible as the prototypes obtained from RP, especially for complex shapes. Manufacturers can use conceptual prototypes as a promotional tool to sell their products, i.e., they can use RP prototypes to quickly allow users to compare and evaluate the new products they develop and determine the optimal appearance. ②Checking design quality. Taking mold manufacturing as an example, the traditional method is to open the mold on a CNC machine according to the geometric shape, which is too risky for expensive and complex molds, and any carelessness in the design may cause irreparable damage. Using RPM technology, the parts to be die-cast can be accurately manufactured before the mold is opened, and various subtle problems and errors in the design can be seen at a glance on the model, greatly reducing the risk of blind mold opening. the model made by RP can also be used as a CNC copy milling machine against the mold. ③ Functional inspection. Using prototypes to quickly perform functional tests of different designs to optimize product design. For example, the design of a fan, etc., can obtain the best fan blade surface and the lowest noise structure. 4, rapid forming process room is highly automated, long time continuous, simple operation can do day and night unattended, once the machine is turned on, can automatically complete the whole workpiece processing. 5, the manufacturing process of rapid forming technology does not require the input of tooling, and its cost is only related to the operating cost of the forming machine, material cost, and operator's salary, and has nothing to do with the batch of products, which is suitable for the manufacturing of the single piece, small-batch, and special and new trial products. 6, reverse engineering in rapid modeling has a wide range of applications. Laser 3D scanners, automatic tomography scanners, and many other measuring devices can quickly measure the internal and external contours of objects with high precision and convert them into CAD model data for RP processing. RP-based Rapid Tooling Technology In the field of rapid prototyping technology, the most rapidly developing and obvious growth of production value is Rapid Tooling, RT technology. By applying Rapid Prototyping technology to make Rapid Tooling RP+RT, we can greatly improve the success rate of product development, effectively shorten the development time and reduce the cost by conducting new product trials and small batch production before the final production mold. RP+RT technology provides a new concept and method of manufacturing molds directly from mold CAD models, which integrates the conceptual design and machining process of molds within one CAD/CAM system, creating good conditions for the application of parallel engineering. RT technology adopts RP multi-loop, rapid information feedback design, and manufacturing method, combined with various computer simulation and analysis means, forming a set of A new mold design and manufacturing system. The manufacturing of rapid tooling using rapid prototyping technology can be divided into two categories: direct rapid tooling manufacturing and indirect rapid tooling manufacturing. 1, Direct Rapid Tooling Manufacturing Direct rapid tooling manufacturing refers to the direct fabrication of a mold using different types of rapid prototyping techniques, followed by some necessary post-treatment and machining to obtain the required mechanical properties, dimensional accuracy, and surface roughness of the mold. Currently, the rapid prototyping processes that can directly manufacture metal molds include selective laser sintering SLS, shape deposition manufacturing SDM, and 3D Welding. Direct rapid mold manufacturing links are simple and can more fully exploit the advantages of rapid forming technology, especially in close combination with computer technology, to quickly complete mold manufacturing. For those injection molds that require complex shapes and internal runner cooling, the use of direct rapid mold manufacturing has advantages that cannot be replaced by other methods. Production injection molds can be produced in 5-10 days using the SLS direct rapid mold manufacturing process. 2, Indirect Rapid Tooling Manufacturing Using rapid prototyping master mold and pouring soft materials such as wax, silicone rubber, epoxy resin, or polyurethane, it can constitute a soft mold. The mold life of the injection mold made with this synthetic material can be up to 50-5000 pieces. A hard mold can be made by combining a rapid prototyping master mold or a soft mold with traditional processes such as investment casting, ceramic precision casting, electroforming, or cold spraying, which can produce plastic or metal parts in bulk. Hard molds usually have better machinability and can be partially machined for better accuracy and can be embedded with inserts, cooling parts, and sprue, etc.

Production of high-quality, economic die castings, in addition to a reasonable casting structure, perfect die casting die, and good die casting machine, but also must choose the appropriate die casting alloy. CAMEL dedicated designers in the selection of die casting alloy must consider the die casting stress state, working environment, production conditions, and economic 4 aspects, must also consider the alloy itself comprehensive properties. Die casting alloys selection generally follows the following principles. 1. Sufficient strength and plasticity at high temperatures, no or less thermal embrittlement. 2. Small crystallization temperature range. 3. Sufficient fluidity when the superheat is not high. 4. Small shrinkage. 5. Good physical and chemical properties - wear resistance, corrosion resistance, electrical conductivity, and thermal expansion, etc. 6. Good processability. Types of die casting alloys Die casting alloys are divided into non-ferrous alloys and ferrous alloys, currently widely used non-ferrous alloys, classified as follows Die casting non-ferrous alloys Low melting point alloy: lead alloy, tin alloy, zinc alloys. High melting point alloys: aluminum alloys, magnesium alloys, copper alloys. Properties comparison Comparison of the properties of various die casting alloys The property varies from "1" to "5". "1" means the most desirable, and "5" means the worst. Main alloy material of die casting Among them, the density of die casting aluminum alloy is about 2.7g/cm3, which can also be called light metal, and its property characteristics are very suitable for the die casting process. Aluminum alloys is the most used alloy for die casting. Die casting aluminum alloy has the characteristics of low density, high specific strength, good corrosion resistance, wear resistance, good thermal conductivity, good electrical conductivity, good cutting properties, etc. The die casting process is accompanied by a fast solidification rate, making the die casting alloy slightly better than gravity casting and casting alloys with the same chemical composition. yl112 alloy has better machinability. The 518 alloy with magnesium as the main alloying chemical element has the best machinability. The A390 alloy with high silicon content and incipient silicon phase have the worst machinability.

Die Casting Process (Fully automatic die casting cycle) Mold cleaning Mold preheating Paint spraying Placement of inserts Mold closing Pouring Press injection Solidification Open the mold Push out and take the parts Die casting can be divided into two categories: hot chamber die casting machine pressure casting and cold chamber die casting machine pressure casting, of which cold chamber die casting machine pressure casting is divided into vertical, horizontal and full vertical die casting machine die casting. Commonly Used Die Casting Machine Die Casting Process 1, Hot press chamber die casting machine die casting process The pressure chamber of hot die casting machine is in the insulated crucible molten alloy, the press injection parts are mounted on top of the crucible, and when the press injection punch rises, the molten alloy enters the chamber through the inlet. When the die is closed and the press punch is pressed down, the molten alloy fills the die through the nozzle along the channel and cools and solidifies. When the die punch returns, the die is opened and the part is taken, completing a die casting cycle. 2, Die casting process of vertical cold chamber die casting machine The center of the vertical cold chamber die casting machine is parallel to the parting surface of the mold, which is called vertical side chamber. After closing the mold, the molten alloy poured into the chamber is held by the counter punch which has sealed the nozzle hole; when the press injection punch goes down to the molten alloy, the counter punch starts to descend to open the nozzle and the molten alloy is pressed into the mold cavity; after solidification, the press injection punch returns and the counter punch rises to cut off and push out the residual material; after the residual material is taken away, the counter punch descends to the original position and the mold is opened to take the parts, completing a die casting cycle, this die casting machine is especially suitable for This kind of die casting machine is especially suitable for the production of die casting machine with center gate. 3, Horizontal cold chamber die casting machine die casting process The center line of the horizontal cold chamber die casting machine is perpendicular to the mold parting surface, called horizontal chamber. After the mold is closed, the molten alloy is poured into the chamber, and the injection punch is pushed forward to fill the cavity through the sprue; when the mold is opened, the injection punch pushes out the remaining material, the die pushing out mechanism pushes out the die casting, and the punch is reset to complete a die casting cycle. 4, The die casting process of all vertical cold chamber die casting machine The die casting machine with vertical arrangement of die closing mechanism and press injection mechanism is called all-vertical die casting machine, which can be divided into the following two types. 1) The die-casting process of the punch head press type all-vertical cold chamber die-casting machine. The molten alloy is first poured into the chamber and then the die is closed, the pressurized injection punch rises to press the molten alloy into the mold cavity, and after cooling and solidifying, the die is opened and the die casting is pushed out, and the punch is reset to complete a die casting cycle. 2) The die casting process of punch down type all vertical cold chamber die casting machine. After the mold is closed, the molten alloy is poured into the mold, and when the pressurized punch goes down to the molten alloy, the counterpunch goes down to open the channel, and the molten alloy is pressed into the mold cavity through the sprue; after solidification, the pressurized punch returns, and the counterpunch goes up to cut off and push out the remaining material. After the remaining material is taken away, the counter punch is reset to complete a die-casting cycle. In the above die-casting method, horizontal cold chamber die-casting machine is most widely used. Global Brand Of Horizontal Cold Press Chamber High Pressure Die Casting Machine: China: LK, YIZUMI, HAITIAN, SANJI, ZITAI, RUIDA, YANHING, MULER Japan: TOYO ,TOSHIBA , UBE U.S.: HPM (Acquired by YIZUMI in 2011) Switzerland: BUHLER German: FRECH Italy: IDRA , ITALPRESSE

What is mold temperature control? and how to balance the heat energy in the mold processing program? Then we introduce the related MTC, heat energy balance, and cooling system to propose solutions. The Influence Of Mold Temperature On Mold And Die Casting Mold temperature is one of the important factors affecting the quality of die castings, but it is often not strictly controlled during the production process. Especially in the production of complex die castings, only the temperature is controlled within a certain range to produce qualified die castings, and this temperature range is relatively narrow. At this time, the mold temperature must be strictly controlled. In each die-casting cycle, the temperature in the mold cavity changes. The heat source to raise the temperature of the mold is the heat brought in by the molten metal, and the heat energy is converted into the part of the mechanical energy consumed by the molten metal to fill the cavity. When the mold receives heat, it also radiates heat to the surroundings. If the heat absorbed by the mold and the heat dissipated in a unit of time is equal and reaches an equilibrium state, it is called the heat energy balance of the mold. What is MTC(Mold Temperature Controller) The mold temperature controller controls the temperature of the mold during thermal equilibrium within the optimal working temperature of the mold. The temperature control of the mold is achieved through the heating and cooling system of the mold. In the continuous die-casting process, the mold temperature goes through a cycle of rising and falling for each injection. In order to avoid the thermal shock of the molten metal on the low-temperature die-casting mold and shorten the life of the die, the molten metal will be chilled to lose fluidity, increase the line shrinkage, cause cracks or cracks to affect the quality of the die-casting, the mold must be fully preheated before die-casting. In continuous production, especially when die-casting high melting point alloys, the mold heats up very quickly, causing the molten metal to stick to the mold, the die-casting part is pushed out and deformed, the mold is partially stuck or even damaged, and the mold opening time is prolonged, reducing the productivity, and the die-casting part cools slowly. And make the crystal grain coarse. Therefore, when the temperature of the die-casting mold is too high, cooling measures should be taken to keep the mold in thermal equilibrium. How Does CAMEL Balancing Heat Energy CAMEL designs ample cooling lines on the fixed side and movable side to control the heat energy balance to get the best cycle-time and part quality. The balanced heat energy also lowers the risk of die cracking.