Microstructure and mechanical properties of a new high-strength Mg–6 Zn–4 Al–1 Sn alloy were investigated. Microstructure of the as-cast Mg alloy exhibited partially divorced characteristics. The dendritic structur...Microstructure and mechanical properties of a new high-strength Mg–6 Zn–4 Al–1 Sn alloy were investigated. Microstructure of the as-cast Mg alloy exhibited partially divorced characteristics. The dendritic structure of the Mg–6 Zn–4 Al alloy was significantly refined with the addition of 1%(in weight) Sn, but Mg2 Sn phases were not formed. In addition, an icosahedral quasi-crystal phase was formed in the as-cast Mg–6 Zn–4 Al–1 Sn alloy. It was found that after the double-aging treatment through two different heat treatments on the Mg–6 Zn–4 Al–1 Sn alloy, the precipitates were finer and far more densely dispersed in the matrix compared with single-aged counterpart, resulting in a significant improvement in tensile strength with yield strength, ultimate tensile strength and elongation of 175 MPa, 335 MPa and 11%,respectively.展开更多
The effect of double-aging on the microstructure and mechanical properties of a RS/PM Al-Li alloy has been investigated.The results show that the ductility of the alloy can be greatly improved by the treatment of prio...The effect of double-aging on the microstructure and mechanical properties of a RS/PM Al-Li alloy has been investigated.The results show that the ductility of the alloy can be greatly improved by the treatment of prior-aging at 170 C for 4 h and second-step aging at 190'C for 18 h after solid solutioning.The formation of a large amount of composite precipitates(AlLi_(3)/Ab(Li,Zr))with suitable size,narrowing ofδ(Al_(3)Li)precipitate-free zone(PFZ)at grain boundaries and more dispersive precipitation of S'(Al_(2)CuMg)phases along substructures are responsible for the improvement of the ductility of the studied alloy.展开更多
基金supported by the National Basic Research Program of China (No. 2013CB632205)the National Key Research and Development Program of China (No. 2016YFB301105)
文摘Microstructure and mechanical properties of a new high-strength Mg–6 Zn–4 Al–1 Sn alloy were investigated. Microstructure of the as-cast Mg alloy exhibited partially divorced characteristics. The dendritic structure of the Mg–6 Zn–4 Al alloy was significantly refined with the addition of 1%(in weight) Sn, but Mg2 Sn phases were not formed. In addition, an icosahedral quasi-crystal phase was formed in the as-cast Mg–6 Zn–4 Al–1 Sn alloy. It was found that after the double-aging treatment through two different heat treatments on the Mg–6 Zn–4 Al–1 Sn alloy, the precipitates were finer and far more densely dispersed in the matrix compared with single-aged counterpart, resulting in a significant improvement in tensile strength with yield strength, ultimate tensile strength and elongation of 175 MPa, 335 MPa and 11%,respectively.
基金supported by China National High Tech.Committee。
文摘The effect of double-aging on the microstructure and mechanical properties of a RS/PM Al-Li alloy has been investigated.The results show that the ductility of the alloy can be greatly improved by the treatment of prior-aging at 170 C for 4 h and second-step aging at 190'C for 18 h after solid solutioning.The formation of a large amount of composite precipitates(AlLi_(3)/Ab(Li,Zr))with suitable size,narrowing ofδ(Al_(3)Li)precipitate-free zone(PFZ)at grain boundaries and more dispersive precipitation of S'(Al_(2)CuMg)phases along substructures are responsible for the improvement of the ductility of the studied alloy.