Microstructure evolution and mechanical properties at high temperature of selective laser melted AlSi10Mg
来源期刊：JOURNAL OF MATERIALS SCIENCE TECHNOLOG2021年第3期
论文作者：Y.Cao X.Lin Q.Z.Wang S.Q.Shi L.Ma N.Kang W.D.Huang
文章页码：162 - 172
摘 要：In this study,the microstructure and tensile properties of selective laser melted AlSilOMg at elevated temperature were investigated with focus on the interfacial region.In-situ SEM and in-situ EBSD analysis were proposed to characterize the microstructural evolution with temperature.The as-fabricated AlSilOMg sample presents high tensile strength with the ultimate tensile strength（UTS） of ～450 MPa and yield strength（YS） of ～300 MPa,which results from the mixed strengthening mechanism among grain boundary,solid solution,dislocation and Orowan looping mechanism.When holding at the temperature below 200℃ for 30 min,the micro structure presents little change,and only a slight decrement of yield strength appears due to the relief of the residual stress.However,when the holding temperature further increases to 300℃ and 400℃,the coarsening and precipitation of Si particles in α-Al matrix occur obviously,which leads to an obvious decrease of solid solution strength.At the same time,matrix softening and the weakness of dislocation strengthening also play important roles.When the holding temperature reaches to 400℃,the yield strength decreases significantly to about 25 MPa which is very similar to the as-cast Al alloy.This might be concluded that the YS is dominated by the matrix materials.Because the softening mechanism counteracts work hardening,the extremely high elongation occurs.
Y.Cao1,2，X.Lin1,2，Q.Z.Wang1,2，S.Q.Shi1,2，L.Ma1,2，N.Kang1,2，W.D.Huang1,2
1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University2. Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design, MIIT China, Northwestern Polytechnical University
摘 要：In this study,the microstructure and tensile properties of selective laser melted AlSilOMg at elevated temperature were investigated with focus on the interfacial region.In-situ SEM and in-situ EBSD analysis were proposed to characterize the microstructural evolution with temperature.The as-fabricated AlSilOMg sample presents high tensile strength with the ultimate tensile strength（UTS） of ～450 MPa and yield strength（YS） of ～300 MPa,which results from the mixed strengthening mechanism among grain boundary,solid solution,dislocation and Orowan looping mechanism.When holding at the temperature below 200℃ for 30 min,the micro structure presents little change,and only a slight decrement of yield strength appears due to the relief of the residual stress.However,when the holding temperature further increases to 300℃ and 400℃,the coarsening and precipitation of Si particles in α-Al matrix occur obviously,which leads to an obvious decrease of solid solution strength.At the same time,matrix softening and the weakness of dislocation strengthening also play important roles.When the holding temperature reaches to 400℃,the yield strength decreases significantly to about 25 MPa which is very similar to the as-cast Al alloy.This might be concluded that the YS is dominated by the matrix materials.Because the softening mechanism counteracts work hardening,the extremely high elongation occurs.
关键词：
