Refill friction stir spot welding of EN AW-7075-T6 to EN AW-7075-T6 sheets -Part 1: Effect of the welding parameters on the microstructure, surface temperature and hardness of refill friction stir spot welds of EN AW-7075-T6

摘要

Refill friction stir spot welding is a solid-state spot welding process for joining lightweight sheets in the overlap configuration by means of frictional heat and mechanical work. In this experimental research, refill friction stir spot welds of aluminium alloy EN AW-7075-T6 sheets, used in aircraft applications for its light weight and high strength, were produced. The joining time, rotational speed and plunge depth were varied. Surface temperature measurements in the proximity of the weld provided an indication of the heat input. The microstructure and hardness of the sheet joints were investigated and related to the welding parameters and heat input.