The ZrB 2 particles firstly modified Mg_(94)Zn_(2.5)Y_(2.5)Mn 1 alloy.And the microstructures and mechanical performances of the modified alloys were studied systematically.The results showed that the moderate additio...The ZrB 2 particles firstly modified Mg_(94)Zn_(2.5)Y_(2.5)Mn 1 alloy.And the microstructures and mechanical performances of the modified alloys were studied systematically.The results showed that the moderate addition of ZrB 2 accelerated the development of long-period stacking ordered(LPSO)structure and refined the grain size.The grains in ZrB 2-modified alloys were nearly equiaxed with a homogeneous size.When 0.0075 wt%ZrB 2 was added,the as-cast alloy with the finest grains(24.87μm)presented desirable mechanical properties(especially ductility)with maximum tensile strength and ductility of 225 MPa and 17.5%,respectively.展开更多
Microstructures and precipitation behaviours of Mg94Y4Zn2 (at. %) extruded alloy during solution treatment and ageing processes were investigated. Three major phases were observed in the as-cast Ug94Zn2Y4 alloy:α-...Microstructures and precipitation behaviours of Mg94Y4Zn2 (at. %) extruded alloy during solution treatment and ageing processes were investigated. Three major phases were observed in the as-cast Ug94Zn2Y4 alloy:α-Mg, block shaped 1 8R long period stacking ordered (LPSO) phase and Mg24Y5 cuboid particles. After homogenization and extrusion, the block shaped LPSO phase changed into plate-like shape aligned along the direction of extrusion. During solution treatment, a small fraction of LPSO phase was transformed from 18R structure to 14H type. The nano-scale β' phase with its close-packed planes being perpendicular to the direction of both α-Mg and LPSO structure was precipitated at ageing stage. The coexistence of β' and LPSO phase contributes to the strengthening of the alloy, with microhardness for the matrix and LPSO structures reaching 145.8 and 155,0 HV, respectively.展开更多
基金Project (BK2010392) supported by the Natural Science Foundation of Jiangsu Province of ChinaProject (3212000502) supported by the Innovation Foundation of Southeast University,China
基金support of Shanxi key laboratory of advanced magnesium-based material,Na-tional Natural Science Foundation of China(No.51474153 and 51574175)Ph.D.Programs Foundation of Ministry of Education of China(20111402110004)。
文摘The ZrB 2 particles firstly modified Mg_(94)Zn_(2.5)Y_(2.5)Mn 1 alloy.And the microstructures and mechanical performances of the modified alloys were studied systematically.The results showed that the moderate addition of ZrB 2 accelerated the development of long-period stacking ordered(LPSO)structure and refined the grain size.The grains in ZrB 2-modified alloys were nearly equiaxed with a homogeneous size.When 0.0075 wt%ZrB 2 was added,the as-cast alloy with the finest grains(24.87μm)presented desirable mechanical properties(especially ductility)with maximum tensile strength and ductility of 225 MPa and 17.5%,respectively.
基金the financial support of the project from the Natural Science Foundation of Jiangsu Province of China(No.BK2010392)the Innovation Foundation of Southeast University(No.3212000502)the Opening Project of Jiangsu Key Laboratory of Advanced Materials
文摘Microstructures and precipitation behaviours of Mg94Y4Zn2 (at. %) extruded alloy during solution treatment and ageing processes were investigated. Three major phases were observed in the as-cast Ug94Zn2Y4 alloy:α-Mg, block shaped 1 8R long period stacking ordered (LPSO) phase and Mg24Y5 cuboid particles. After homogenization and extrusion, the block shaped LPSO phase changed into plate-like shape aligned along the direction of extrusion. During solution treatment, a small fraction of LPSO phase was transformed from 18R structure to 14H type. The nano-scale β' phase with its close-packed planes being perpendicular to the direction of both α-Mg and LPSO structure was precipitated at ageing stage. The coexistence of β' and LPSO phase contributes to the strengthening of the alloy, with microhardness for the matrix and LPSO structures reaching 145.8 and 155,0 HV, respectively.