Vacuum Brazing Aluminum: A Comprehensive Guide
Vacuum Aluminum Brazing (VAB) is a sophisticated and reliable process used for joining aluminum components. This process is often preferred over other methods due to its ability to produce cleaner assemblies, meet demanding braze-joint integrity requirements, and manufacture critical devices.Get more news about Vacuum Brazing Aluminum,you can vist our website!
The Process
VAB is a fluxless process, meaning it does not use flux to remove oxides. Instead, vacuum pumps evacuate the furnace, reducing the oxygen level in the brazing chamber and inhibiting oxide formation3. This results in a cleaner assembly and a high-quality braze joint.
Design Guidelines
The components to be vacuum aluminum brazed must be properly prepared to ensure excellent capillary action1. The mating surfaces to be brazed should be flat and less than 0.003 inches (max)1. Milled or turned surfaces with a 32 to 64 micro-inch surface finish work best1. It’s important to note that machining can impart residual stresses into the Aluminum components, which will be released during the thermal cycle of the braze run.
Post-Brazing Operations
After brazing, the assembly will be annealed, and usually, it will be sent for heat treatment to a T6 before final machining. The heat-treating operation can also cause warpage. Therefore, it’s crucial that the components have at least 0.050 inches of excess material to be final machined after brazing.
Applications
VAB is a reliable means of manufacturing devices such as critical microchannel devices, cold plates, cold walls, radiators, microwave antennas, and waveguides. It’s used in diverse industries, ranging from aerospace to transportation and packaging.
Conclusion
In conclusion, Vacuum Aluminum Brazing is a highly efficient and reliable process for joining aluminum components. It offers numerous advantages, including improved structural integrity, better conductivity, and less distortion4. However, it requires careful preparation and post-brazing operations to ensure the highest quality results1. As technology advances, the applications and capabilities of VAB are expected to expand, further solidifying its position as a go-to process in various industries.
