The production technology of metal thermal pad includes cutting, aluminum extrusion, metal powder jet forming and so on.
A. cutting: turning, drilling, milling and grinding. In the forming process of thermal conductive sheet, cutting technology is required to obtain some special and fine shapes.The advantage is that according to different ways, cutting tools, can be applied to a variety of purposes.The disadvantage is the tool wear fast, most of the need for manual participation or automation control, high cost.Suitable for all heat conducting sheet: sheet (heat absorbing bottom, fin, etc.) forming, heat conducting sheet grooving, bottom dressing, special carving, etc.
B. Aluminum extrusion: heat the original ingot of aluminum alloy to about 520~540℃, use mechanical pressure, make the aluminum liquid flow through the extrusion mold made of mold steel, cool the aluminum liquid at the outlet of the mold, make it solidified quickly, and become the first embryo of thermal conductive sheet with continuous parallel structure. Advantages are less investment, low technical threshold, short development cycle, easy to put into production; Mold cost, low production cost, large output; It can be used in a wide range of applications. It can be used to manufacture either individual heat sink or the fin part of the combined heat conductor. The disadvantage is that the fin shape is relatively simple and it is not possible to obtain a large (> 20) lane-to-length ratio. Suitable for heat sink processing, aluminum extrusion technology is mainly used to produce the initial blank of sheet fin or cylindrical fin.
C. Metal powder jet forming: mainly using materials with high melting point and high heat conduction (such as copper). The metal powder is sprayed at high speed to make the first embryo of thermal conductive sheet directly, and then sintered at high temperature to make the finished product with considerable strength and density. The advantage lies in the metal powder sintering in one, high thermal conductivity; Heat conducting sheet with complex shape can be machined, the designer has less limitation. Disadvantages for raw materials, equipment, mold cost, complex process, low yield, not easy to mass production. It is mainly applied to electronic products with high calorific value and space limitation. The manufacturing cost and price are very high.
