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The production process of aluminum alloy casting plants revolves around raw material processing, melting, forming, and post-processing. Each link needs to be strictly controlled, and precautions should be taken throughout the entire process to ensure the quality of castings and production safety.   The production process begins with raw material preparation, where aluminum ingots and scrap aluminum are mixed in proportion, impurities are removed, and then put into the melting furnace. In the melting stage, the raw materials are melted by fuel or electric heating, and the temperature is raised to 700-750 ℃. Alloy elements are added to adjust the composition, while degassing and slag removal are carried out to remove gases and impurities from the melt.   The molding process can be selected based on the process, including die-casting, sand casting, or low-pressure casting. Die casting uses high pressure to press molten metal into the mold cavity for rapid prototyping; Sand casting relies on sand mold cavity forming and is suitable for complex castings; Low pressure casting uses low-pressure gas to press the melt into the mold, resulting in a denser casting. After forming, wait for the casting to cool to room temperature for demolding or sanding.   Post treatment includes cleaning burrs and burrs on the surface of castings, removing sprues and risers; Heat treatment is carried out according to the requirements to improve the mechanical properties of castings through heating, insulation, and cooling; Perform surface treatment, such as grinding and spraying, to enhance appearance and corrosion resistance.   The precautions need to be implemented in stages. Temperature monitoring is required during melting. Excessive temperature can cause alloy element burnout, while insufficient temperature can result in poor melt flowability; Thoroughly remove gas and slag, otherwise the casting is prone to porosity and inclusions.   During the molding stage, the temperature of the mold should be checked, and the die-casting mold should be preheated to 150-250 ℃ to avoid cold mold affecting the fluidity of the melt; Sand molds need to ensure breathability to prevent the formation of porosity in castings; Moderate force is applied during demolding to prevent deformation of the casting or damage to the mold.   In post-processing, suitable tools should be used to clean burrs to avoid scratching the surface of the casting; The heat treatment temperature and time need to be precisely controlled, and different alloys correspond to different parameters to prevent performance from not meeting standards.   The production environment needs to be kept ventilated, and the smoke generated from smelting needs to be treated before being discharged; Operators need to wear protective equipment to avoid burns from high-temperature melt; Regular equipment inspections are required, and the transmission components of furnaces and die-casting machines need to be lubricated to prevent malfunctions.   Raw material storage should be classified and stacked to avoid mixing; Waste aluminum recycling needs to be screened to prevent the introduction of harmful impurities; Avoid squeezing and deformation when stacking castings.   The production process of aluminum alloy casting plants is interrelated, with precautions involving process parameters, equipment maintenance, personnel protection, etc. Strictly following them can improve the qualification rate of castings, ensure orderly production, and provide qualified blanks for subsequent processing.

The die casting of aluminum castings is a process of injecting molten aluminum under high pressure into metal molds, achieving mass production through rapid filling and cooling. Its characteristics are closely related to mold design and process parameters, and it is suitable for the manufacturing of various industrial components. Outstanding production efficiency is a significant advantage. The mold can be opened and closed in one go to complete the formation of a casting. The single-mode cycle is usually 30-90 seconds, and the multi cavity mold can produce 2-8 parts at a time, suitable for batch production of more than 100000 pieces per year. After forming, the surface roughness of the casting can reach Ra1.6-6.3 μ m, and in most cases, there is no need for secondary processing and it can directly enter the assembly process. The structural adaptability has clear boundaries. It can form complex inner cavities and thin-walled structures, with a wall thickness of 0.5-1mm (depending on the casting size), but the wall thickness needs to be uniform, with a deviation of no more than 0.3mm, to avoid shrinkage caused by differences in cooling rate. The design height of the reinforcing bars should not exceed 5 times the wall thickness, and the spacing should be maintained at 3-5 times the wall thickness to enhance structural rigidity without hindering metal flow. The material selection needs to match the process characteristics. Commonly used aluminum alloys contain 5% -12% silicon, have good fluidity, and are suitable for complex castings; The alloy containing 3% -5% copper has high strength, but it is prone to sticking to the mold during die casting, and the mold temperature needs to be increased to 200-250 ℃. Pure aluminum has poor fluidity and is only used for simple shaped castings, and the die-casting pressure needs to be increased to 80-120MPa. Process parameters affect the quality of molding. The temperature of the aluminum liquid should be controlled between 650-700 ℃. Excessive temperature can lead to oxidation, while insufficient temperature can result in incomplete filling; The injection speed is divided into slow injection (0.1-0.5m/s) and fast injection (3-8m/s), and higher speed is required in the fast injection stage of complex cavities. The spacing between the cooling water channels of the mold is 15-30mm, ensuring that the casting solidifies to the demolding temperature within 3-5 seconds. Limitations need to be addressed in a targeted manner. There may be small pores inside the casting, which are not suitable for high temperature (>200 ℃) environments to avoid deformation caused by pore expansion. Cannot form large castings, generally with a single weight not exceeding 50kg and a projected area controlled within 0.5m ². Mold manufacturing has high costs and long modification cycles, making it unsuitable for small batch and multi variety production. Die casting has an irreplaceable advantage in mass production of complex aluminum castings due to its high-pressure and rapid process characteristics. Clarifying the boundaries of structural design, selecting materials and process parameters reasonably, can fully leverage its efficiency advantages while avoiding potential defects, and meet the requirements of industrial components for accuracy and consistency.

Aluminum castings involve various surface treatment methods, such as aluminum phosphating. Research has shown that guanidine nitrate has good water solubility, low dosage, and rapid film formation, making it an effective promoter for aluminum phosphating. Fluoride can promote film formation, increase film weight, and refine grain size; Mn2+and Ni2+can significantly refine the grain size, make the phosphating film uniform and dense, and improve the appearance of the phosphating film; As the concentration of Zn2+increases, the membrane weight also increases; The PO4 content has a significant impact on the weight of the phosphating film, and increasing the PO4 content increases the weight of the phosphating film.   Next is the alkaline electrolytic polishing process for aluminum, which can produce good polishing effects by adding appropriate additives to NaOH solution. The feasibility of using DC pulse electrolytic polishing method to polish aluminum materials under alkaline conditions shows that the use of pulse electrolytic polishing method can achieve the leveling effect of DC constant voltage electrolytic polishing, but its leveling speed is slow.   The key to environmentally friendly chemical polishing of aluminum castings and aluminum alloys is to add some compounds with special effects to the base solution instead of nitric acid. Firstly, it is necessary to analyze the three acid chemical polishing process of aluminum, with a particular focus on studying the effect of nitric acid.   The main function of nitric acid in aluminum chemical polishing is to suppress pitting corrosion and improve polishing brightness. Based on the chemical polishing test in pure phosphoric acid monosulfate, it is believed that the special substance added to phosphoric acid monosulfate should be able to inhibit pitting corrosion, slow down overall corrosion, and must have good leveling and brightening effects.   The electrochemical surface strengthening treatment of aluminum and its alloys is also one of the surface treatment processes for aluminum castings. In the neutral Na2WO4 mixed system, the concentration of film-forming promoter is controlled at 2.5-3.0g/l, the concentration of complexing agent is 1.5-3.0g/l, the concentration of Na2WO4 is 0.5-0.8g/l, the peak current density is 6-12A/dm2, and weak stirring can obtain a complete, uniform, and glossy gray series inorganic non-metallic film layer.

Aluminum castings have a loose structure, high porosity, and contain various metal and non-metal impurities, making the quality of the anodized film difficult. In order to obtain normal oxide film quality and avoid white spots after anodic oxide film staining, the following measures can be taken.   (1) High voltage and high current density impulse method. In the early stage of anodizing, high voltage and high current are applied to connect the small and large "islands" that were originally divided by impurities into pieces through high current impact. The specific process is as follows:   At the initial stage of anodizing, the voltage is adjusted to about 30V, and the current density is about 2~2.5A/dm2. After 3~5min, the normal anodizing voltage is adjusted back, anodizing for 50min, and then after full cleaning, a satisfactory oxide film can be dyed, and the white spots basically disappear.   The slight drawback of the above method is that if the casting has screw holes, it may slightly enlarge. Therefore, it is necessary to control the high current density, high voltage anodizing time, and prevent the temperature of the anodizing solution from rising too quickly. During continuous production, cooling measures should be taken for the anodizing solution.   (2) Surface polishing method for castings. Grinding can fill the pores of castings with aluminum powder, serving as a bridge connecting the isolated "islands" of impurities. The actual effect of this method is slightly inferior to method (1), because the polished aluminum powder sometimes does not play a real filling and bridging role, and some parts of the filling material will be corroded and fall off during alkali corrosion and anodizing processes.   (3) Shot peening method on the surface of castings. Before using the shot blasting method, the author used a round headed hammer to strike, with the original intention of closing the gaps that block the "islands" by striking, achieving the goal of connecting them into pieces. The result was significant. Considering that the use of shot peening can greatly improve the efficiency, the effect after anodizing and dyeing is better than both of the above methods.   If the wall thickness of general cast aluminum parts can meet the pressure requirements during shot peening, using a higher pressure is beneficial for improving the quality requirements of shot peening. The squeezing of shot particles can achieve the effect of closing pores and gaps, and can improve the strength and cleanliness of the surface of cast aluminum parts.   Someone mentioned why white spots do not appear on the surface of unprocessed castings after anodizing and dyeing, because the surface of the castings has a dense oxide film.

According to relevant media reports, due to the loose structure and high porosity of aluminum castings, which contain various metal and non-metal impurities, white spots are prone to appear on the anodized film after dyeing, and the quality of anodized film on aluminum castings is difficult. Experts suggest that the following methods can be used to avoid this problem: using high-voltage and high current density impact method. In the early stage of anodizing, high voltage and high current are applied to connect the small and large "islands" that were originally divided by impurities into pieces through high current impact. Secondly, the surface polishing method for castings. Grinding can fill the pores of castings with aluminum powder, serving as a bridge connecting the isolated "islands" of impurities. Thirdly, the surface shot blasting method for castings. Before using the shot blasting method, the author used a round headed hammer to strike, with the original intention of closing the gaps that block the "islands" by striking, achieving the goal of connecting them into pieces. The result was significant. These methods can effectively prevent white spots from appearing on the anodized film of aluminum castings after dyeing, thereby improving their quality.

1. Layer by layer solidification Pure aluminum or eutectic aluminum alloys do not have a solidification zone where liquid and solid coexist during the solidification process, so the solid in the outer layer and the liquid in the inner layer are clearly separated by a boundary line (solidification front) on the cross-section. As the temperature decreases, the solid layer thickens and the liquid layer decreases, reaching directly to the center of the aluminum casting. This solidification method is layer by layer solidification. 2. Pasty solidification If the crystallization temperature range of aluminum alloy is wide and the temperature distribution of aluminum castings is relatively flat, during a certain period of solidification, there is no solid layer on the surface of the casting, and the solidification zone where liquid and solid coexist runs through the entire section, similar to cement solidification, paste like solidification, and then solidification, which is called paste like solidification. 3. Intermediate solidification Most solidification occurs between layer by layer and paste like solidification, known as intermediate solidification. Generally speaking, the quality of aluminum castings is closely related to their solidification method. Gold has strong filling ability, which is conducive to preventing shrinkage and porosity; Pasty solidification is the solidification method for obtaining compact aluminum castings. In order to improve the quality of aluminum castings, increase labor productivity, and reduce costs, it is necessary to conduct a specific analysis of the aluminum castings and select a reasonable process plan when determining the casting process plan.

Aluminum castings often encounter oxidation slag inclusions, most of which are dispersed on the surface of the aluminum casting, and some are distributed in the corners where ventilation is not possible. The ports of these media are mostly yellow or gray white in color. During mechanical processing, it can be observed, and the reasons for such situations can also be found during acid or alkali washing. There are several points to consider: the materials used in the furnace are not clean enough, and the amount of recycled materials is too large; The designed pouring system is not very reasonable; The slag in the aluminum casting alloy liquid is not cleaned thoroughly enough; During the pouring process, the slag was also brought in due to improper operation; And to prevent a short period of calm after refining and deterioration treatment. In order to effectively solve these problems, we need to master a reasonable and standardized pouring speed, and try to avoid involving gas as much as possible; Organic substances cannot be mixed into the core sand to reduce the gas generation of the material; Improve the exhaust function of the core sand to make it stronger; Reasonably select high-quality cold iron; Design flaws in improving the pouring system.

Aluminum castings can be manufactured as aluminum die-casting automotive parts, aluminum die-casting automotive engine fittings, aluminum die-casting engine cylinders, aluminum die-casting gasoline engine cylinder heads, aluminum die-casting valve rocker arms, aluminum die-casting valve supports, aluminum die-casting power accessories, aluminum die-casting motor end caps, aluminum die-casting housings, aluminum die-casting pump housings, aluminum die-casting building accessories, aluminum die-casting decorative accessories, aluminum die-casting guardrail accessories, aluminum die-casting aluminum wheels, and other parts. Characteristics of shrinkage defects: Shrinkage in aluminum castings generally occurs in thick areas near the sprue, at the transition between thick and thin walls, and at thin-walled areas with large flat surfaces. When in the as cast state, the fracture surface is gray, and the light yellow color after heat treatment is grayish white, light yellow or gray black. It appears as a cloud like structure on X-ray film. Severe filamentous shrinkage can be found through X-ray, fluorescence low magnification fracture inspection methods. The causes are: 1. Poor feeding effect of the riser. 2. Too much gas content in the furnace material. 3. Overheating near the inner runner. 4. Too much moisture in the sand mold, the sand core is not dried. 5. Coarse alloy grains. 6. Improper position of the casting in the mold. 7. Too high pouring temperature and too fast pouring speed Methods to prevent aluminum castings: 1. Pour molten metal from the riser and improve the riser design. 2. The furnace material should be clean and corrosion-resistant. 3. Set up a riser at the shrinkage area of the casting, and place a cold iron or a combination of cold iron and riser. 4. Control the moisture content of the molding sand and dry the sand core. 5. Take measures to refine the grain size. 6. Improve the position of the casting in the mold and reduce the pouring temperature and speed.

Pure aluminum castings are not difficult to make. Nowadays, when applied to various heat sinks, you may think that it is easy to stick to the mold during the die-casting production process. The following are recommendations for die-casting of multi-year aluminum alloys.   1》 The selection of release agent should be appropriate (not cheap, it is better to buy pure aluminum alloy release agent specially developed by Germany and Taiwan Dunhuang, which is very useful)   2》 Maintenance of melting temperature (the boiler temperature should be kept above 720 ° C as much as possible, and the temperature probe should be made of silicon carbide material, which is more accurate and not easily corroded by aluminum liquid)   3》 The use of graphite material in the crucible of the melting furnace is not likely to cause a large temperature difference between the upper and lower parts.   4》 The surface temperature of the mold should not be lower than 220 ° C.   5》 The cooling time after injection is not easy to be too long, and the ejection time after mold opening is within 0.3 seconds.   6》 The feeding port of the mold is thicker than that of aluminum alloy.   7》 The smoother the flow rate between the channel and the feed inlet during injection, the better.   8》 Spray the product automatically as far as possible, otherwise the mold surface temperature is not easy to maintain stability.

The quality of aluminum castings has a significant impact on the performance of mechanical products. For example, the wear resistance and dimensional stability of aluminum castings in machine tools directly affect the accuracy and lifespan of the machine tools; The accuracy and surface roughness of the impeller, housing, and hydraulic components of various pumps directly affect the working efficiency, energy consumption, and cavitation development of pumps and hydraulic systems; The strength and resistance to cold and heat of aluminum castings such as cylinder blocks, cylinder heads, cylinder liners, piston rings, and exhaust pipes of internal combustion engines directly affect the working life of the engine.   The weight and size range of aluminum castings are very wide, with light ones weighing only a few grams and heavy ones reaching up to 400 tons. Thin ones have a wall thickness of only 0.5 millimeters, while thick ones can exceed 1 meter. The length can range from a few millimeters to over ten meters, meeting the usage requirements of different industrial sectors. In casting production, it is necessary to control and inspect the quality of aluminum castings. Firstly, it is necessary to establish process guidelines and technical conditions for the control and inspection of raw materials, auxiliary materials, and each specific product. Strictly control and inspect each process according to the process rules and technical conditions. Conduct quality inspection on the finished aluminum castings afterwards. Reasonable testing methods and appropriate testing personnel should be equipped. Generally, the appearance quality of aluminum castings can be judged by comparing sample blocks to determine the surface roughness of aluminum castings; Minor cracks on the surface can be inspected by coloring and magnetic particle methods. The internal quality of aluminum castings can be inspected and judged using methods such as audio, ultrasound, eddy current, X-ray, and gamma ray.   The commonly used casting methods for aluminum castings are resin sand casting and lost foam casting, followed by special casting methods such as metal mold casting, investment casting, gypsum mold casting, etc. Sand casting can be divided into clay sand molds, organic binder sand molds, resin self hardening sand molds, lost foam molds, and so on. When the wet mold cannot meet the requirements, consider using clay sand surface dry sand mold, dry sand mold or other sand molds. The weight of castings cast with clay green sand can range from a few kilograms to tens of kilograms, while castings produced with clay dry molds can weigh up to tens of tons. The casting method of aluminum castings should be adapted to the production batch. Low pressure casting, die-casting, centrifugal casting and other casting methods are only suitable for mass production due to the expensive equipment and molds.

Friends who are familiar with aluminum castings should know that due to factors such as process or materials, the surface of the manufactured aluminum castings will be very rough. In order to meet the usage requirements, such as performing alkali etching treatment on the product to improve the surface quality of aluminum castings. But this operation is not that easy, and many aspects need to be noted, such as the presence of various compounds and other inclusions between metals; Uneven chemical composition segregation caused by organizational looseness; The surface of aluminum castings appears rough due to factors such as the lack of dense oxide film formation during cooling after casting. At the same time, we also found that alkali etching treatment can play a key role in improving this problem. However, controlling the alkaline etching time is a difficult and critical point. If the alkaline etching time is short, aluminum castings may not be completely removed; However, if the time is too long, it can also cause excessive corrosion of the product, resulting in changes in tolerance dimensions. So a good solution is to change the alkali etching process, which means that alkali etching treatment is carried out after casting. This not only improves the surface quality, but also prevents various problems caused by alkali etching. After the alkaline etching treatment of the product is completed, 1:1 hydrochloric acid can be used for rapid light treatment, which will achieve more ideal results.

Aluminum castings refer to devices in equipment made of aluminum alloy or pure aluminum using special processing methods of casting. The quality of aluminum castings directly affects the performance and functionality of mechanical products. For example, the wear resistance and dimensional stability of aluminum castings used on machine tools directly affect the accuracy and lifespan of the entire machine tool. For example, the size and profile standards of the impeller and housing of the pump, as well as the internal cavity and surface roughness of the hydraulic components, also directly affect the working efficiency between the hydraulic system and the pump, as well as the development of energy consumption and cavitation. In addition, some internal combustion engine cylinder blocks, cylinder liners, cylinder heads, piston rods, and exhaust pipes also have high requirements for strength and resistance to cold and heat, as they directly affect the service life of the entire engine during operation. Because aluminum castings have a wide range of weight and size, with lighter ones weighing only a few grams and heavier ones weighing up to 400 tons, but thinner ones with a wall thickness of only 0.5 millimeters and thicker ones not exceeding one meter, and lengths ranging from a few millimeters to tens of meters, aluminum castings can meet the requirements of various industrial sectors. Strict inspection and control of the quality of aluminum castings must be carried out throughout the entire casting production process. We first need to start with the raw materials used in manufacturing, as well as the auxiliary materials, to achieve different control schemes and technical conditions for different products. During the casting process, each step must be strictly controlled according to the rules of the process and relevant technical conditions. After the manufacturing is completed, it is necessary to conduct corresponding quality inspections on the finished aluminum castings. So this requires a complete inspection plan and qualified testing personnel.

The casting process of aluminum castings is actually a core technology mainly based on low-pressure casting of electromagnetic pumps, so the composite purification technology of aluminum smelting and forming, as well as the core technology of the entire manufacturing industry, produce high-quality aluminum castings in modern technology. In fact, aluminum castings may encounter some problems during their daily storage and use, such as the phenomenon of mold formation. Below, the editor will take you to understand why aluminum castings undergo mold formation. Firstly, there are issues with the environment in which aluminum castings are stored, such as not being too dry and having relatively low humidity and temperature, making it more suitable for mold growth, ultimately leading to mold growth in the aluminum castings. Secondly, during the casting process, the surface of the aluminum casting contains super dissolved substances. If this is the case, it will automatically absorb moisture into the air, leading to a corrosion reaction in the original pool. This creates a more suitable environment for mold growth. Once again, due to the corrosion of the original battery on the aluminum casting, alkaline compounds precipitated on the surface. After deliquescence, the humidity and temperature were relatively moderate, which led to the rapid growth of mold. Afterwards, oil and plant fibers appeared on the surface of the aluminum castings, which are suitable environments for mold growth. If the temperature and humidity are just right, the mold will grow quickly.

Aluminum castings must not have invasive pores during the casting process. So, how can we prevent such problems? Firstly, it is necessary to strictly control why gas enters aluminum castings and how to effectively prevent it? Strictly control the content of gas substances that may be emitted from the core sand and molding sand, as well as the moisture content of the wet mold. Secondly, the compactness and breathability of the sand mold also need to be carefully controlled, because the lower the breathability of the sand mold, the higher the compactness, and the tendency for invasive pores to occur is much greater. Therefore, under the condition that the sand mold has sufficient strength, we should try our best to reduce the compactness of the sand mold. In fact, using coarse back sand in the surface sand is an effective measure to provide breathability of the sand mold. Further improving the exhaust capacity of the sand mold and core can effectively enhance the exhaust function by adding exhaust holes on the lower mold. However, it is important to keep the exhaust holes in the sand core unobstructed, and it is also advisable to install an exhaust riser at the top of the aluminum casting. Therefore, we can adopt a more reasonable pouring system. We can appropriately increase the temperature of the entire pouring process, because increasing the pouring temperature can effectively allow sufficient time for the invading gas to be completely discharged. Therefore, during pouring, it is important to control the pouring height and the entire pouring speed, ensuring a smooth and flowing filling of the liquid metal. Afterwards, we can appropriately improve the quality of the entire smelting process in the liquid metal. Firstly, we can try to reduce the sulfur content in the molten iron as much as possible, effectively improve the overall flow performance of the molten iron, and prevent excessive flying oxidation of the liquid metal. This can effectively reduce the resistance when the entire gas is discharged.

There are many classifications of aluminum alloys during casting, including aluminum copper alloys, aluminum zinc alloys, etc. Why distinguish it chemically? Because the performance of the product is closely related to its chemical composition. Aluminum silicon alloy has excellent casting performance due to its properties. Aluminum silicon alloy also has some compatibility with gray cast iron. Aluminum copper alloy has poor casting performance and a limited solidification range because it does not contain eutectic components. In fact, in general production, the solidification range of aluminum silicon alloy is relatively small, so the efficiency of its riser shrinkage naturally increases. And it is easy to obtain castings with good density. Other alloys are the opposite. Because alloys are easily oxidized and absorbed, we should ensure a smooth flow of aluminum liquid during casting. The time for degreasing will be determined based on the actual situation of the workpiece. The time cannot be too long, otherwise the oil removal will not be thorough, but it cannot be too short, otherwise the surface of the workpiece will become dark. Due to the need to frequently salvage the residue and debris inside, the editor suggests changing the tank fluid every 4 months.

When it comes to aluminum castings, everyone may not be unfamiliar with them because they can be seen everywhere in our daily lives, such as household items or car parts. Many people have also asked me what the process specifications for this product are, but I don't know much about it. However, I have found Wuxi Weiliqiang Metal Manufacturing Co., Ltd. where many professional people have explained a lot to me. I have come back and summarized it myself. If you also have this need, please take a look with me. The object obtained by deforming or strengthening the tissue of the object is an aluminum casting. We must use professional inspectors to conduct inspections during operation and establish reasonable operating procedures. The organization of this product has changed. It can also greatly improve the impact toughness, formability, and durability of the product. The subsequent heat treatment can improve the strength, hardness, and formability of all components. Another point is that if the production process is unreasonable or the quality of the raw materials is poor, it will definitely affect the internal quality and appearance of the product, and in severe cases, it may lead to the product being scrapped. So we must follow the process rules of the product in every process. The next step in the process is to inspect the finished product. If you need a product, Wuxi Weiliqiang Metal Manufacturing Co., Ltd. is your good choice.

What is gravity casting? Answer: Gravity casting, in simple terms, can also be called gravity casting, which uses gravity to inject molten metal into a mold to form a casting. In a broad sense, sand casting, metal casting, investment casting, lost foam casting, etc. are all gravity casting, while the narrow definition refers to metal casting, which is different from non-ferrous casting as the two are not the same. After understanding the definition of gravity casting, let's now explain the defects of aluminum alloy gravity casting. Defect 1: Shrinkage 1. Causes (1) During the crystallization process, the shrinkage of the casting is insufficient. (2) The position of introducing the alloy liquid is incorrect. (3) The temperature of each part is inappropriate, which violates the principle of solidification. (4) The paint has peeled off. (5) The pouring temperature is too high or the speed is too fast. (6) The cooling speed of the casting is too slow, or the casting has burrs. 2. Preventive measures (1) For parts of the casting that are relatively thick, a riser should be installed with a reasonable height. (2) Pour evenly or supplement pouring. (3) Choose the appropriate coating according to the actual situation, and if it falls off, it should be evenly replenished. (4) Reduce the pouring temperature and slow down the pouring speed appropriately. Defect 2: Cracks 1. Causes (1) There are sharp corners and uneven thickness on the castings, sometimes with significant differences. (2) The local temperature of the mold is too high, or the pouring temperature is too high. (3) The cold iron is not placed correctly. 2. Preventive measures (1) Remove sharp corners from the casting and ensure even transition of the casting wall thickness. (2) The position of the sprue and runner should be selected correctly, and the pouring temperature should be controlled well. (3) Cold iron should be placed correctly to increase the feeding capacity of the riser.

One of the major advantages of using aluminum castings is the low manufacturing cost, while the processability is not bad. It can also save a lot of energy consumption. From this, it is not difficult to see that the application of such materials in the future is sustainable and continuously developing. The scope of using aluminum castings is particularly wide, and the involved industry fields are very diversified. Among these industries, if the batch size is large, When it comes to the aspect of having a wide variety and high technical requirements, the automotive industry should be the top choice. Aluminum castings perform well in terms of strength and corrosion resistance, especially with a very low alloy density, making them more suitable for use in the automotive industry. Using aluminum castings instead of steel and iron to manufacture cars is truly a wise choice. Not only does it become easier to operate, There will be no pollution at all, and all the properties of the aluminum castings will be maximized.

There are many issues to be considered when performing die-casting on aluminum castings. We must take all of them into account comprehensively. For instance, it is necessary to determine whether the molten metal can flow in a stable state after being poured into the system, and whether there will be any separation or vortex phenomena. It is necessary to take into account whether there are sharp corners or dead zones in the aluminum castings, whether the cross-sectional area of the pouring system has changed in any way, etc. All these need to be thoroughly understood by us. The main purpose of aluminum castings is to pour the metal solution into the specified model, and after cooling, re-solidification and cleaning and shaping, achieve the expected shape and performance. This casting method is also one of the basic processes in the current mechanical manufacturing industry. The manufacturing objects that the aluminum casting manufacturing industry needs to face change as rapidly as flowing water. If the objects put forward special requirements, it will pose more challenges for the aluminum castings. This is also one of the important indicators to measure the comprehensive vision of the mechanical machine tool industry.

When heat treating aluminum castings, their melting point is very low, making them prone to overheating. The temperature deviation after heating is relatively small. Aluminum castings have very high requirements for the accuracy of temperature measurement instruments. If the insulation deviation after heating is relatively large, the purpose of strengthening cannot be achieved. Therefore, it can be seen that controlling the heating temperature of hot aluminum castings is the key in the entire process. After numerous experiments, it has been confirmed that there is a connection between the temperature generated during manual operation and the duration. If the aging temperature is relatively high, the holding time will be shortened, while if the aging temperature is relatively low, the holding time will be extended to a certain extent. If handled in this way, it will have a large degree of dispersion for large-scale production. If the quality of the final product is not well controlled, the application of the second method can increase the pass rate of the product and also ensure the process quality of the product.