Thermal Spray Deposition Technology for Production of Complex Heat Transfer Devices

电子电路将它们接收的大部分电能作为热量耗散，这些热量必须被去除。电路板安装在金属板上，金属板具有内部通道，水通过该通道循环。对流道设计的研究表明，随着通道直径的减小，热传递增加，但这增加了通过它们的压降。此外，使用常规技术难以钻出小直径（< 1mm）通道的网络。我们已经开发出一种新的方法，制造冷却通道的铜和铝板使用热喷涂技术。在金属板的表面上以任何期望的图案铣削通道。通道的确切形状是使用3D打印机由水溶性聚合物制成的。插入物被放置在通道中，并且使用双丝电弧系统将熔融金属喷涂在金属板的表面上。然后将板置于超声水浴中数小时以溶解聚合物插入物，使喷涂表面下的通道保持开放。发现制造的板比商业冷板提供显着更高的传热。可以在相同的板面积中加工冷却通道的多个通道，从而增加被液体润湿的表面积。较长的流动路径和通道中的多个弯曲，促进了流动中的湍流并增强了热传递。该技术可用于制造可针对特定电路板布局进行优化的冷板的新颖设计。我们可以在弯曲的冷却板表面制作通道，这对于电池冷却等应用非常重要。该市场评估提案将有助于确定该技术在制造可用于计算机，汽车和其他行业的冷却系统方面的商业需求。

Electronic circuits dissipate most of the electrical energy they receive as heat, which must be removed. Circuit boards are mounted on metal plates that have internal passages through which water is circulated. Research into the design of flow passages has shown that heat transfer increases as the channel diameter is reduced, but this increases the pressure drop through them. Also, it is difficult to drill networks of small diameter (< 1mm) channels using conventional techniques. We have developed a new method of fabricating cooling channels in copper and aluminum plates using thermal spray techniques. Channels are milled on the surface of a metal plate in any desired pattern. Inserts in the exact shape of the channels are made using a 3D printer out of a water-soluble polymer. The inserts are placed in the channels and molten metal is sprayed on the surface of the metal plate using a twin wire-arc system. The plate is then placed in an ultrasonic water bath for several hours to dissolve the polymer inserts, leaving open the channels under the sprayed surface. The plates fabricated were found to provide significantly higher heat transfer than commercial cold plates. It was possible to machine multiple passes of the cooling channel in the same plate area, increasing the surface area wetted by the liquid. A longer flow path, and multiple bends in the channel, promoted turbulence in the flow and enhanced heat transfer. This technique can be used to make novel designs of cold plates that can be optimized for specific circuit board layouts. We can make channels on the surface of curved cooling plates, which is important for applications such as battery cooling. This Market Assessment Proposal will help identify commercial demand for this technology in making cooling systems that can be used in the computer, automotive and other industries.