Effects of Plasma Nitriding on the Tensile Properties of Al-Mg-Si

Effects of plasma nitriding on the tensile behavior of Al-Mg-Si alloy were investigated in this study. The specimens were nitrided at 70 W input pulsed DC power at 1 mbar pressure of nitrogen for 4 h using glow discharge plasma. The formation of aluminum nitride layer on the specimen's surface was confirmed by the XRD analysis. Stress-strain curves of both un-nitrided and nitrided specimens were obtained using Universal Testing Machine. The comparison of these curves reveals that yield stress, ultimate tensile stress, percentage elongation, and stress relaxation rate decrease after plasma nitriding. The changes in the tensile properties after nitriding have been correlated with the changes in the microstructure of the specimens as observed using scanning electron microscope.