Effect of Thermal Aging on the Corrosion and Mechanical Properties of Friction Stir Welded 250 Grade Maraging Steel

摘要

The main objective of this work is to investigate the microstructure and mechanical properties of friction stir welded 250 grade Maraging steel. Successful welds were made using W-25%Re-4%HfC pin tools in forge control mode at a rotational speed of 200 rev • min~(-1) and a travel speed of 50.8 mm • s~(-1). Retained austenite was identified in the weld nugget. Formation of retained austenite in the weld nugget is strongly influenced by the weld process parameters. The effects of post weld aging on the corrosion and mechanical properties of the welds were evaluated and compared to the parent material. Post-weld aging at 482 ℃ for 15 h resulted in peak hardness across the weld nugget.