环境温度对砂型铸造AlSi7Mg材料力学性能的影响

浇注了3组AlSi7Mg材料砂型试棒,利用拉伸测试、扫描电镜及金相组织分析等手段,研究了砂型铸造AlSi7Mg材料的力学性能。结果表明:当环境温度从-40℃升至100℃时,AlSi7Mg材料的抗拉强度、屈服强度均有所降低,其中抗拉强度和屈服强度分别降低了14.3%和9.8%;材料的伸长率随着温度的提高不断增加;低温变形过程中材料显微组织显示共晶硅颗粒细小,分布较为均匀,试棒断口显微形貌显示局部分布着小的韧窝,具有准解理+韧窝型断裂的特征。

Influence of ambient temperature on the mechanical properties of sand-cast AlSi7Mg alloy

3 sets of sand - cast AlSi7Mg test rods are prepared and their mechanical properties are studied by means of tensile testing, SEM and metallurgical structure analyses. Testing resuhs indicate that the tensile strength and yield strength of AlSiTMg material decreases respectively by 14.3% and 9.8% when the ambient temperature rises from -40℃ to100℃ , while its elongation increases with the rise of temper- ature. Evenly distributed and fine eutectic silicon particles are found in its microstructure during low tem- perature deformation, and the microstructures at the fractures of the test rods are characterized by locally distributed dimples and quasi- cleavages.