加热：利用射频加热Weld

　　加热：利用射频加热Weld

　　当我们想到射频的时候，我们中的大多数人都会联想到无线电、数据链和通信的图像，有一个射频设计工程师的整个亚文化，其工作与通信无关。相反，这些工程师使用射频加热，焊接和密封金属物体。我们可以熟悉的一个例子是感应炉顶部，加热金属锅和锅，而表面仍然凉爽。

　　电磁感应使用的感应线圈，与RF驱动，导致电阻加热效应的涡流引起的金属在靠近射频场。金属，称为基座，吸收热，热传导到一个更大的面积或体积（用于液体加热），或导致融化，融合，或焊接非常有效。没有爆炸性气体，烟雾或化学物质，使这个过程的工厂和自动化机械线的理想选择。

　　Figure 1： A 25 mm metal bar can be made red hot using 15 kW of RF energy at 450 kHz.

　　This article looks at inductive heating using RF energy and discusses design solutions and applications where this technology can be used. All parts， data sheets， tutorials， and development kits referenced here can be found online at Digi-Key’s website.

　　Not just for cooking

　　For decades， inductive heating has been used on factory floors for sealing and packaging of metal containers. Early patent drawings show how relatively few components can implement an effective solution （Figure 2）。 Comparatively speaking， it is only fairly recently that inductive heating for cooking has been offered on medium- to low-cost cooking surfaces. However， we all have used products that have been inductively heat sealed. We are all familiar with cans of food that require an opener to break the vacuum seal. If you look carefully at the tops of these cans， you will see that the lids are welded to the cans; dedicated machines use specially designed inductive heaters driven by high-power RF to fuse the lids to the cans quickly， reliably， and repeatedly.