Vacuum Brazing of 304 Stainless Steel and Oxygen-Free Copper

Vacuum brazing is an effective and reliable joining process for bonding 304 stainless steel with oxygen-free copper, especially in applications requiring high thermal efficiency, corrosion resistance, and leak-tight performance. This combination is commonly used in heat exchangers, vacuum components, power electronics, and cooling systems where both strength and conductivity are essential.

The process is carried out in a high-temperature vacuum brazing furnace, which provides an oxygen-free environment to prevent oxidation of both materials. A carefully selected brazing filler metal—typically silver- or copper-based—is placed between the stainless steel and oxygen-free copper parts. When heated to the brazing temperature, the filler metal melts and flows uniformly into the joint by capillary action, forming a strong metallurgical bond.

Vacuum brazing minimizes thermal distortion and residual stress while maintaining the excellent thermal and electrical conductivity of oxygen-free copper and the corrosion resistance of 304 stainless steel. The resulting joint is clean, dense, and highly reliable, capable of withstanding thermal cycling and demanding service conditions.

Due to these advantages, vacuum brazed assemblies of 304 stainless steel and oxygen-free copper are widely used in high-performance industrial, electrical, and thermal management applications, where long-term reliability and efficiency are critical.