Estimation of Brazing Temperature in Aluminium Heat Exchangers by Using Alpha Phase Measurement Techniques

During the conventional brazing process of aluminium heat exchanger component (HEX), the temperature measurement of component in brazing furnace is a general requirement in order to control & achieve the required brazing temperature (around 590°C - 610°C) to ensure efficient brazing joints of the aluminium products. The temperature measurement & monitoring during brazing is usually done with the help of temperature sensors alongwith the data logging system, in fact this is currently a widely used method. However, there are many drawbacks in this type of method for which a suitable solution needs to be developed. In this study, a possible development of simulation tool on the basis of data from Al-Si phase diagram & Lever rule, predicting the temperature on the component during brazing using this tool & comparing w.r.t actual measured data are discussed in detail. As a part of further validation, the data from both the data-logger as well as the estimated temperature from the simulation for the same sample at a specific defined location were compared and it was found that the simulated values were in close agreement with the measured values.