Superplastic Behaviour of a Rapidly Solidified Al-17Si Alloy
来源期刊:JOURNAL OF MATERIALS SCIENCE TECHNOLOG1992年第1期
论文作者:陈桂云 吴越 王国志 张永昌
文章页码:9 - 14
摘 要:<正> A rapidly solidified Al-17Si alloy was pre-pared by the ultrasonic gas atomization andextrusion method.Its superplasticity was studiedunder constant cross-head speed tensile test condi-tion over the temperature range of 450℃ to 550℃and strain rate range of 1.67×10-4 to 6.17×10-2 s-1.The superplastic behaviour of theas-extruded and the thermomechanically treatedsamples was compared.It was found that thethermomechanical treatment was essential toachieving superplastic deformation.A maximumelongation of 445% was obtained at test tempera-ture of 550℃ and strain rate of 6.17×10-4 s-1.The microstructures before and after deformationwere studied using OM,SEM and TEM.Void for-mation on the primary Si phase interfaces wasfound to have detrimental effect on superplasticity.It was also noted that the primary Si phasecoarsened rapidly during superplastic deformation.The micromechanisms of superplasticity,phasecoarsening and void formation were discussed.
陈桂云,吴越,王国志,张永昌
摘 要:<正> A rapidly solidified Al-17Si alloy was pre-pared by the ultrasonic gas atomization andextrusion method.Its superplasticity was studiedunder constant cross-head speed tensile test condi-tion over the temperature range of 450℃ to 550℃and strain rate range of 1.67×10-4 to 6.17×10-2 s-1.The superplastic behaviour of theas-extruded and the thermomechanically treatedsamples was compared.It was found that thethermomechanical treatment was essential toachieving superplastic deformation.A maximumelongation of 445% was obtained at test tempera-ture of 550℃ and strain rate of 6.17×10-4 s-1.The microstructures before and after deformationwere studied using OM,SEM and TEM.Void for-mation on the primary Si phase interfaces wasfound to have detrimental effect on superplasticity.It was also noted that the primary Si phasecoarsened rapidly during superplastic deformation.The micromechanisms of superplasticity,phasecoarsening and void formation were discussed.
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