die cast aluminum heat sink
Ⅰ）What is Die Cast Aluminum heat sink？
Die cast aluminum heat sink refers to the heat sink manufactured by die-casting process. In the heat dissipation industry, the die-casting process is generally used to manufacture heat sink shells (such as classic communication RRU, AAU, set-top boxes, lamp shells, etc.) and liquid-cooled boxes (such as automobile engine cooling, battery pack shells, and installation space shapes). irregular liquid-cooled products). Die cast aluminum heat sinks are also used in some situations where the use environment is harsh, the structure is complex, and sealing is required. Generally, after the die-casting process completes the product cover plate and base structure, it is sealed into a whole by friction stir welding. Below is a diagram of it
Ⅱ）What is die casting process？
Die casting is a casting method that pours molten alloy liquid into a pressure chamber, fills the cavity of a steel mold at a high speed, and solidifies the alloy liquid under pressure to form a casting. Die casting is a precision casting method. The dimensional tolerances of die castings cast by die casting are very small and the surface accuracy is very high. In most cases, die castings can be assembled and applied without milling. Parts can also be cast directly. Small parts such as general camera parts, typewriter parts, electronic computing devices and ornaments, as well as complex parts of vehicles such as automobiles, locomotives, and airplanes, are mostly manufactured by die casting.
The main difference between die casting and other casting methods is high pressure and high speed.
1) The molten metal fills the cavity under pressure, and crystallizes and solidifies under higher pressure. The common pressure is 15-100MPa.
2）The molten metal fills the cavity at a high speed, usually 10-50 m/s, and some can exceed 80 m/s (the linear speed of the cavity introduced through the inner gate—the speed of the inner gate), so the filling of the molten metal is The molding time is extremely short, and the cavity can be filled within about 0.01-0.2 seconds (depending on the size of the casting).
Ⅲ）Advantages and disadvantages of die casting aluminum heat sink
1） Good product quality
Castings have high dimensional accuracy, generally equivalent to grade 6~7, or even up to grade 4; good surface roughness, generally equivalent to Rz 3.2~20um; high strength and hardness, and the strength is generally 25~30% higher than that of sand casting , but the elongation is reduced by about 70%; the size is stable and the interchangeability is good; it can die-cast thin-walled and complex castings. For example, the current minimum wall thickness of zinc alloy die castings can reach 0.3mm; aluminum alloy castings can reach 0.5mm; the minimum casting hole diameter is 0.7mm; the minimum pitch is 0.75mm.
2)high production efficiency
The machine has high productivity. The cold die-casting machine can die-cast 600 to 700 times in an average of eight hours, and the small hot-chamber die-casting machine can die-cast 3000 to 7000 times in an average of eight hours. The die-casting mold has a long service life. 100,000 times, even millions of times; easy to achieve mechanization and automation.
3)Good economic effect
Because of the advantages of precise dimensions and smooth surface of die castings. Generally, it is used directly without mechanical processing, or the processing volume is very small, so it not only improves the metal utilization rate, but also reduces a large number of processing equipment and man-hours; the castings are cheap; combined die-casting can be used with other metal or non-metallic materials. Saves both assembly man-hours and metal.
1). During die casting, due to the high speed of liquid metal filling the cavity and the unstable flow state, the general die casting method is used, and the casting is prone to pores and cannot be heat treated;
2). For castings with complex concave, die casting is more difficult. High melting point alloys (such as copper, ferrous metals), die casting mold life is low.
3). It is not suitable for small batch production. The main reason is that the manufacturing cost of the die casting mold is high, the production efficiency of the die casting machine is high, and the small batch production is uneconomical.
Ⅳ）Service and ability
1）Design and Simulation
Regis Provide customers with free thermal design simulation solutions and manufacturing feasibility assessment (PFMEA), reduce development costs for customers, shorten the development cycle of die-casting aluminum heat sinks, empower customers, and help customers succeed.
We have 5 die-casting automatic forming machines of 80-500T, the maximum annual processing capacity is 500000PCS, the mold is completed in 15 days, the sample is delivered in 5 days, and the mass production is delivered in 15 days. Multiple engineers take turns to follow up service for each project 24 hours to ensure the completion of product quality and quantity.
1) Product structure inspection: The mechanical dimensions of die-casting aluminum heat sinks are inspected through height gauges, CMM, thread gauges and other equipment to ensure that they meet customer requirements.
2）Heat dissipation performance test: The heat dissipation performance and pressure loss parameters of the die-casting aluminum heat sink are tested by a thermal resistance tester to ensure compliance with customer requirements.
3)Leakage test: Fill the closed die-casting aluminum liquid-cooled heat sink with air, and the pressure of the filling air is 1.5-2 times the working pressure of the die-casting aluminum liquid-cooled heat sink system. Put the die-casting aluminum liquid-cooled heat sink into water and observe the cooling Whether there are bubbles out of the die-casting aluminum liquid-cooling heat sink, the die-casting aluminum liquid-cooling heat sink with bubbles is defective. This is the most basic and most important reliability test of the die-casting aluminum liquid-cooling heat sink, which requires 100% test.