Effect of heat treatment on the properties of plasma arc welded TRIP800 steel

In this study, the effect of heat treatment applied at various temperatures on the properties of plasma arc welded TRIP800 steel has been examined extensively. For this purpose, the low temperature heat treatment was carried out at -50, -20, and 0 degrees C for 2 h on a set of welded samples. Moreover, the heat treatment process was also applied for 2 h at various temperatures (i.e., 100, 200, 300, 400, 500, 600, 800, and 1000 degrees C) for another group of plasma arc welded TRIP800 steels. In addition, the properties of a set of samples without any heat treatment were determined in as-welded condition for a comparison. The mechanical properties of all samples were determined, and microstructures of samples were evaluated. As a result, the low temperature heat treatment applied at the specified temperatures did not have a significant effect on the ultimate tensile strength, and ductility of the joint but affected the yield strength positively. Besides, the ultimate tensile strength of heat treated samples also diminished with increasing processing temperature. It was found that the yield strength of the heat treatment applied samples showed an increase up to 500 degrees C, while the samples tested at 500 and 600 degrees C showed pronounced yielding behavior.