Based on the 3 factors and 3 levels orthogonal experiment method, compositional effects of Mg, Si, and Ti addition on the microstructures, tensile properties, and fracture behaviors of the high-pressure die-casting Al-xMg-ySi-zTi alloys have been investigated. The analysis of variance shows that both Mg and Si apparently influence the tensile properties of the alloys, while Ti does not. The tensile mechanical properties are comprehensively influenced by the amount of eutectic phase (α-Al + Mg₂Si), the average grain size, and the content of Mg dissolved into α-Al matrix. The optimized alloy is Al-7.49 Mg-3.08Si-0.01Ti (wt%), which exhibits tensile yield strength of 219 MPa, ultimate tensile strength of 401 MPa, and elongation of 10.5%. Furthermore, contour maps, showing the relationship among compositions, microstructure characteristics, and the tensile properties are constructed, which provide guidelines for developing high strength and toughness Al–Mg–Si–Ti alloys for high-pressure die-casting.

基于三因素和三水平正交试验方法，镁，硅和钛的添加对高压压铸Al- x Mg - y Si- z Ti的组织，拉伸性能和断裂行为的影响已经研究了合金。方差分析表明，Mg和Si都明显影响合金的拉伸性能，而Ti则没有。拉伸机械性能受共晶相量（α-Al+ Mg ₂Si），平均晶粒尺寸和溶解在α-Al基体中的Mg含量。优化后的合金为Al-7.49 Mg-3.08Si-0.01Ti（wt％），其抗拉屈服强度为219 MPa，极限抗拉强度为401 MPa，伸长率为10.5％。此外，还绘制了等高线图，显示了成分，微观结构特征和拉伸性能之间的关系，这为开发用于高压压铸的高强度和高韧性Al-Mg-Si-Ti合金提供了指导。