TY - JOUR T1 - Study and Investigation on the Effect of Presence of Interlayer on the Microstructure, Mechanical Properties and Fracture Mode of AISI 321 Stainless Steel Resistance Spot Welds TT - مطالعه و بررسی اثر حضور لایه واسط بر ریزساختار، خواص مکانیکی و تغییر حالت شکست اتصالات حاصل از جوشکاری مقاومتی نقطه ای فولاد زنگ نزن 321AISI JF - JWSTI JO - JWSTI VL - 4 IS - 1 UR - http://jwsti.iut.ac.ir/article-1-212-en.html Y1 - 2018 SP - 101 EP - 112 KW - Resistance Spot Welding KW - AISI 321 Stainless Steel KW - Phase Transformations KW - Mechanical Properties KW - Fracture Mode N2 - In this paper, numerical and empirical investigations of the effect of AISI 347 stainless steel interlayer on the microstructure, mechanical properties and fracture mode of AISI 321 stainless steel resistance spot welds have been conducted. For this purpose, two types of joints, the first free from inter layer and the second contains interlayer with 0.05 mm thickness as well as difference currents and times,were evaluated. In order to examine the mechanical properties including maximum force and tensile mode, tensile – shear test of the spot welds was done. The obtained results indicated that an increase in the welding time and current resulted in a change in fracture mode from interfacial to peripheral owing to an increase in fusion zone volume. The change in the chemical composition because of the presence of interlayer and an increase in cooling rate caused the formation of different phases as well as observation of the dispersed Martensite phase in fusion zone. M3 ER -