Al-5Ti-0.25C-8Sr对AM60B镁合金铸态显微组织及性能的影响

Effect of Al-5Ti-0.25C-8Sr on the As-Cast Microstructures and Properties of AM60B Magnesium Alloy

研究了Al-5Ti-0.25C-8Sr对AM60B镁合金显微组织及性能的影响.结果表明:Al-5Ti-0.25C-8Sr对AM60B具有良好的细化和变质效果.添加质量分数为0.1%的Al-5Ti-0.25C-8Sr时,α-Mg显著细化,β相由连续或半连续状转变为颗粒状,平均晶粒尺寸由265μm降低到约78μm;但当Al-5Ti-0.25C-8Sr加入量大于0.1%时,镁合金晶粒有粗化趋势;AM60B的抗拉强度和显微硬度随着Al-5Ti-0.25C-8Sr添加量的增加先升高后下降,当加入量为0.1%时具有最大值.

The effect of Al-STi-0.25C-8Sr master alloy on the microstructure and mechanical properties of AM60B magnesium alloy was studied. The results show that the AI-STi-0. 25C-8Sr master alloy exhibited good grain-refining and modification performance. The optimum refinement can be obtained with 0. 1% Al-STi- 0.25C-8Sr addition. The grain size of α-Mg reduced from 265μm to 78μm, and the shape of β phase changed from a continuous or discontinuous form to particulate. When the addition of A1-STi-0. 25C-8Sr master alloy is above 0. 1% , the grains become coarse. With increasing A1-STi-0. 25C-8Sr master alloy, the tensile strength and microhardness of AM60B magnesium alloy increase and then decrease. The maxium values are obtained at 0.1%.