Aluminum die castings refer to equipment devices made from pure aluminum or aluminum alloy casting. Due to the low strength of pure aluminum, the current industrial manufacturing is generally common in aluminum alloy castings. Aluminum alloy die casting has been developed for many years, because of its casting performance, high stability, smooth and delicate surface, casting high dimensional accuracy, high strength and hardness, raw materials can be recycled, the economic cost cost-effective and other significant advantages, in the metal manufacturing industry has a place, is widely used in automotive parts manufacturing, aviation, ships, motors, communications, electronic digital manufacturing, construction, home appliances and furniture, LED lighting, handicrafts, guardrail fittings and new energy and other demanding fields. High-quality, high-precision, high-performance, high-toughness aluminum alloy castings have gradually become an indispensable presence in various fields of production and manufacturing, die-casting and other processes have become the most widely used casting process for aluminum or aluminum alloy products.
Six advantages of aluminum alloy die castings:
- high strength. Aluminum alloy castings have a smaller density than cast steel and cast iron, so the strength is higher than both, while the weight is lighter. So if the same load environment, the use of aluminum alloy can greatly reduce the overall weight, so in the power machinery, aerospace and transportation equipment casting, aluminum castings can be said to have significant advantages, naturally more widely used.
- Strong durability: Since aluminum is a material with strong stability and oxidation resistance, aluminum alloy castings will not easily corrode and rust. In addition, aluminum castings will generally be sprayed on the surface of a layer of electrostatic powder and fluorocarbon coatings, which makes the aluminum castings can maintain a long time without fading, so it is very suitable for decorative decoration and home appliances, furniture and decorative products manufacturing field. And because aluminum can maintain strong corrosion resistance even in acidic environments, so it is also widely used in the chemical industry.
- Strong thermal conductivity. Pure aluminum and aluminum alloy castings because of good thermal conductivity, it is often used as a chemical or power machinery in the field of heat exchange devices or thermal conductivity parts.
- plasticity: because of the low melting point of aluminum, ductility and very good, so can be used to cast a variety of molding. And because of the latent heat of solidification of aluminum, the same environment in the liquid aluminum to take a longer time to solidify, that is to say, aluminum can be longer than other materials such as cast steel cast iron to maintain the liquid state and mobility, coupled with the toughness of aluminum is also very strong, so for some of the casting molds within the structure of the casting of complex castings, aluminum is more suitable.
- High safety: Tests show that for strong winds, strong earthquakes, weathering and other external influences, aluminum alloy castings have a strong ability to resist. And the use of aluminum castings can be lighter overall structure weight, installation, handling, construction and maintenance are easier, but also can correspondingly reduce the occurrence of dangerous situations.
- 6. Special creativity: aluminum or aluminum alloy castings can make some special pattern decorations to meet the preferences of different users, so it is very suitable for use in the field of decorative decoration and furniture making.
What are the manufacturing processes of aluminum castings?
For aluminum castings, the casting process is divided into three main types: pressure casting, gravity casting and squeeze casting. The entire casting process can be summarized in the following steps: aluminum/aluminum alloy melting - model manufacturing - casting solidification - demolding - cleaning. -Cleaning. The following one by one to introduce the three casting process.
- pressure casting referred to as die casting, refers to in addition to gravity in addition to the external force, instantaneous pressure injection of molten aluminum or aluminum alloy into the mold casting cavity of the process. Pressure casting can be subdivided into vacuum casting, centrifugal casting, low-pressure casting, and pressurized casting, and rely on the pressure of the die casting machine to complete the casting.
- gravity casting refers to the molten aluminum or aluminum alloy through its own gravity into the mold casting cavity in the process,. gravity casting can be subdivided into the sand casting process and the hard mold casting process.
- Sand casting process because of its use of mold materials is inexpensive and easy to obtain, the process is also relatively simple, and very suitable for aluminum castings of a single piece or mass production, so it can be said that the aluminum casting manufacturing process in the "basic operation".
- The hard mold casting process is also called the metal casting process, liquid aluminum or liquid aluminum alloy will be injected into the metal casting, after cooling and solidification to obtain the casting of a form of technology. The metal mold is usually made of higher-strength aluminum alloy or other hard metals, which can be used repeatedly for many times, and the whole process can be understood as injection molding.
- The extrusion casting process is also called the liquid forging process, the specific process is to talk about the molten state of aluminum or aluminum alloy poured directly into the open mold, and then sealing the mold so that liquid aluminum or aluminum alloy in the mold flow filled to the shape of the mold outside, and then apply high pressure to the mold, so that the mold has been solidified aluminum/aluminum alloy to produce plastic deformation, aluminum/aluminum alloy will be solidified at the same time while withstanding the isosteric pressure, finally forming aluminum/aluminum alloy. Unsolidified aluminum/aluminum alloy will be subjected to isostatic pressure while solidification occurs under high pressure, finally forming aluminum/aluminum alloy castings.
- For the time being, the above aluminum casting production process is considered the most commonly used and relatively low-cost way in the industry. In addition to the above, there are ceramic casting, plaster casting and other technologies.
In addition, in aluminum castings in manufacture, the use of the cavity surface has a high degree of finish, and also sprayed through fire-resistant materials and high-temperature adhesives made of fire-resistant coatings, so the production of aluminum casting surface is also very smooth and flat, better than other ordinary metal castings. This also gives aluminum castings a significant advantage - a smooth surface and high casting accuracy, which reduces the amount of work in machining operations, but at the same time, there is not a lot of machining allowance for small and precise parts. The aluminum/aluminum alloy castings produced in this way do not require machining and can be used with only a simple grinding and polishing allowance, which greatly saves the cost of processing time and labor costs, and also saves a lot of pure aluminum/aluminum alloy raw materials.
What is the process flow of aluminum alloy castings?
Aluminum alloy casting is a kind of alloy product with aluminum as the main component, and aluminum and its alloys are widely used in many fields because they have many excellent properties. Aluminum casting is a commonly used method to manufacture aluminum alloy castings, and its process has an important impact on the quality and productivity of the castings. The process flow of aluminum alloy casting will be introduced below:
- Casting Method Selection: aluminum alloy castings can be made by a variety of casting methods, such as sand casting, metal casting, pressure casting and so on. The specific choice of which casting method needs to be based on the specific requirements of the casting, size and production scale and other factors for comprehensive consideration.
- Mold design: according to the specific shape and size of the casting, mold design. In the mold design, need to take into account the strength of the mold, wear resistance, ease of operation and economy and other factors. At the same time, the heating and cooling system of the mold also needs to be considered to ensure that the castings are adequately heated and cooled during the casting process.
- Melting Aluminum: Aluminum is melted into a liquid state and other elements required are added to obtain an aluminum alloy of the desired composition and properties. During the melting process, the heating temperature and time, as well as the type and amount of alloying elements added, need to be controlled.
- Pouring and solidification: Liquid aluminum alloys are poured into molds to form castings through a cooling and solidification process. During this process, the pouring speed and solidification time need to be controlled to avoid defects such as porosity and cracks.
- Demolding and cleaning: The solidified casting is removed from the mold and the surface is cleaned. In the demolding process, attention needs to be paid to avoid deformation or damage to the castings. Cleaning mainly includes removing surface residues, oxidized skin and so on.
- Quality inspection: quality inspection of castings, including size inspection, appearance inspection, non-destructive testing and so on. In the detection process, found unqualified castings need to be reworked or scrapped to ensure that the quality of the castings meet the requirements.
- Performance testing: performance testing of qualified castings, including mechanical properties, corrosion resistance, thermal conductivity and other aspects of the test.
In summary, the process of aluminum alloy castings includes casting method selection, mold design, melting aluminum, pouring and solidification, demolding and cleaning, quality inspection and performance testing and so on. Each link has an important impact on the quality and production efficiency of castings. In order to obtain high-quality aluminum alloy castings, it is necessary to strictly control the quality and process parameters of each link, and to carry out adequate technical communication and collaboration. With the continuous development and progress of science and technology, it is believed that the production process and technology of aluminum alloy castings will be continuously improved and perfected to provide better quality materials and products for industrial development in various fields.
What are the characteristics of aluminum alloy castings?
Aluminum alloy casting is a kind of alloy products with aluminum as the main component, which is widely used in many fields because aluminum and its alloys have many excellent characteristics. The main characteristics of aluminum alloy castings will be introduced below.
- High Strength: aluminum alloy castings have a lower density than cast steel and cast iron, so they are stronger than both while weighing less.
- Strong durability: aluminum alloy castings will not easily suffer from corrosion and rust because the material itself has strong stability and antioxidant ability. In addition, aluminum castings are generally sprayed with a layer of electrostatic powder and fluorocarbon coating on the surface, which makes aluminum castings able to maintain a long period of time without fading, which is very suitable for use in the field of decorative decoration and the manufacture of home appliances, furniture and decorative items.
- Strong thermal conductivity: Pure aluminum and aluminum alloy castings are often used as heat exchange devices or heat conductive parts in the field of chemical or power machinery because of their good thermal conductivity.
- High plasticity: Due to its low melting point and good ductility, aluminum can be used to cast a wide variety of shapes.
- High safety: Tests have shown that aluminum alloy castings are highly resistant to external influences such as strong winds, strong earthquakes and weathering.
- Good fluidity: Aluminum alloy castings have good fluidity because aluminum matrix eutectic alloys have the best fluidity. At the same time, the fluidity of aluminum alloy castings is affected by a variety of factors, including its composition, temperature, and the presence of metal oxides, metal compounds and other contaminants on the surface of the casting of the solid-phase particles.
- Controllable shrinkage: One of the main characteristics of aluminum profile castings is shrinkage, which is divided into three stages from liquid pouring to solidification until cooling to room temperature, namely liquid shrinkage, solidification shrinkage and solid-state shrinkage. The shrinkage properties of aluminum alloy have a decisive influence on the quality of castings, which affects the casting shrinkage size, stress generation, crack formation and dimensional changes.
In summary, aluminum alloy castings have a variety of excellent characteristics, such as high strength, durability, thermal conductivity, plasticity, safety, good fluidity, and shrinkage. These features make aluminum alloy castings widely used in many fields, such as aerospace, automobile manufacturing, machine manufacturing, power electronics, chemical industry, and so on. Meanwhile, with the continuous development of science and technology, the production process and technology of aluminum alloy castings are also improving, and more aluminum alloy castings with excellent characteristics will be developed and applied in the future.