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Joint Formation Under Severely Altered Background Atmosphere In Controlled Atmosphere Brazing Of Aluminum, Cheng-Nien Yu

Theses and Dissertations--Mechanical Engineering

Adverse changes of background atmosphere in a brazing chamber cause qualitative and quantitative deterioration of joint formation in an aluminum brazing process. This study offers an insight into the adverse effects with gradually adjusted atmospheric conditions in terms of oxygen and humidity levels. Corresponding responses of the molten clad flow and the joint formation upon resolidification vs. atmospheric conditions are documented by comparative tests involving self-fluxing and surface-fluxing brazing sheets: 1) in situ and in real time study of the onset of melting, clad flow, and joint formation, and 2) inclined wedge-tee mating tests for brazeability assessment. The surface-fluxing brazing …