Structural examination of aging precipitation in a Mg-Y-Nd alloy at different temperatures

A study was conducted to investigate the hardening precipitation of a Mg Y Nd alloy with composition close to WE54 alloy at various aging temperatures. The crystalline structure, morphology, size of the precipitates, and the orientation relationship (OR) between the precipitates and the matrix were determined by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The starting material was a hot-rolled alloy with the nominal composition of Mg, 5.52 wt% Y, 2.69 wt% Nd, 0.04 wt% Zr, and 0.17 wt% Ni. Solution treatment was performed in an electric furnace at 525 °C for 8 hour, followed by quenching in hot water. Isothermal treatments were carried out at 150 °C and 210 °C in an electric furnace for different lengths of time. The hardness of the specimens was measured using a Vickers hardness tester and XRD was conducted using a Rigaku D/max-2500 diffractometer operating at 40 kV and 30 mA using Cu Kα radiation.