Brazing in a high vacuum environment provides the most process control and produces the cleanest parts, free of any oxidation or scaling. It is the preferred brazing environment for brazing aerospace components, hardening medical devices and other applications that require the absolute highest part quality.
We offer two machine designs for vacuum brazing - Bell Jar Vacuum Systems and Induction Heating Vacuum Furnaces.
In a bell jar vacuum system, parts are directly heated in a fully enclosed chamber, which can be pumped down to 5x10-6 Torr. Special fixturing can be designed for automatic part loading and unloading, This type of system is often used for vacuum brazing steel or nickel alloys with steel.
With a bell jar system, the parts are positioned before the bell jar is lowered into place and the controlled atmosphere is created. In this environment, a high degree of control over the overall process can be achieved and open-air issues of oxidation, scaling and carbon buildup can be virtually eliminated.
An alternative method for vacuum brazing is to use an induction heating vacuum furnace, which is often the best choice for brazing parts of unusual shapes or “orphans” from other heating processes. The difference is that the induction furnace will heat the entire part rather than just a narrowly focused joint area. Quartz viewports can provide access for infrared temperature sensing of each individual part.
The use of induction heating eliminates the long heat cycle-time requirements of a conventional vacuum furnace. Through the use of induction, the necessary heat is produced quickly, efficiently and directly into a small graphite susceptor, which radiates the heat uniformly into the part.
GH IA offers a free parts evaluation service for vacuum brazing. Simply send us samples of your parts and tell us about your process - we'll analyze your application requirements, determine the optimum combination of RF power, inductor configuration and atmosphere for your parts and give you our best advice!