Effect of Pouring Temperature on Microstructure and Properties of New Vanadium Microalloyed Casting Magnesium Alloy

The casting experiments for the new magnesium alloy Mg-9 Al-1 Zn-0.6 V used for automotive parts were carried out at different pouring temperatures.The microstructure,tensile properties and corrosion resistance of the obtained magnesium alloy were tested and analyzed.The results show that with the pouring temperature increasing from 680 ℃ to 730 ℃,the tensile strength of the magnesium alloy increases first and then decreases,and the corrosion potential of the alloy presents a positive shift first and then negative displacement,companying improvement in microstructure,tensible properties and corrosion resistance of the samples.Compared with those of the sample obtained at pouring temperature of 680 ℃,both the tensile strength and yield strength of the sample at 710 ℃ increase by 18 MPa,and the corrosion potential positively shifts by 85 mV while the elongation after fracture decreases by 1% for the sample at 710 ℃.The optimum pouring temperature of the novel magnesium alloy Mg-9 Al-1 Zn-0.6 V is determined at 710 ℃.