Microstructure and Mechanical Properties of Friction Stir Welded 17-4 Martensitic Stainless Steel

摘要

In this study, friction stir welding (FSW) which is a solid state joining process was investigated with the objective of understanding the microstructure and mechanical properties of welded joints. Successful welds were produced with a W-25%Re-4%HfC pin tool at a rotational speed of 200 rev·min~(-1) and at a travel speed of 50.8 mm·sec~(-1). The effects of post weld aging on the mechanical properties of the welds were evaluated. Microhardness decreased with the increase in aging temperature for both parent and welded materials. The tensile properties of friction stir welds after the post weld aging were comparable with the parent material.