Determination of optimal brazing frequency by solution of thermal and electromagnetic models

Abstract

Control of the thermal cycles in induction heating has now been achieved, as a result of the use of software that simulates electrical and thermal phenomena. In brazing, however, the results are more disappointing. This is because, in comparison with the classical cases of heating before forging, or of thermal processing, the charge consists of at least three more or less separate parts and the thermal cycles of these must be simultaneous. First, relying on the resolution of Maxwell equations applied to a homogeneous cylinder, the present paper describes the problem of determining the optimal brazing frequency, which is a fundamental parameter in solving the multiple charge heating problem. Then a model is presented that will allow solution in the general case of both electromagnetic and thermal equations in a coupled manner. The general method is illustrated with the example of brazing carbide blades onto a tempered steel body.