Ultra-high strength Mg-9Gd-4Y-0.5Zr alloy with bi-modal structure processed by traditional extrusion
Ultra-high strength Mg-9Gd-4Y-0.5Zr alloy with bi-modal structure processed by traditional extrusion
复制标题
传统挤压加工的双峰结构超高强度Mg-9Gd-4Y-0.5Zr合金
DOI：
10.1007/s12540-016-6325-x
复制
发表时间：
2016-11-01
影响因子：
3.5
通讯作者：
Zhang, Y. F.
中科院分区：
文献类型：
--
作者：
Hong, M.;Shah, S. S. A.;Zhang, Y. F.
通常情况下，多尺度组织可以导致铝合金和钢的综合强度和塑性，但在镁合金中的相关研究还很少报道。本研究采用传统的一步挤压工艺，成功地获得了一种具有超高强度的双峰(Mg-9Gd-4Y-0.5Zr)合金。表征样品具有两种成分的双峰组织，即具有强烈基纤维织构的拉伸粗晶区和再结晶细晶区。经400°C挤压和200°C-60h峰值时效处理后，双峰结构样品具有优异的力学性能，最终强度为508 Mpa，延伸率为8%。超高强度可以归因于其在拉伸的粗晶和弥散的纳米析出物中强烈的挤压织构。这种独特的双峰结构可以很容易地通过一步挤压生产出来，在超高强度和理想塑性的镁合金的工业应用中是相当可靠和低成本的。
It is usual to observe that multi-scale structures can lead to combined strength and ductility both in aluminum alloys and steels, but related research has been seldom reported yet in magnesium alloys. In this study, applying traditional one step extrusion, we have successfully obtained a bimodal (Mg-9Gd-4Y-0.5Zr) alloy capable of ultra-high strength. The characterized sample reveal a bi-modal microstructure with two constitutions, i.e. stretched coarse-grain region with strong basal fiber texture and recrystallization fine-grain region. The bi-modal structured sample exhibit excellent mechanical properties with an ultimate strength 508 MPa and elongation 8% via 400 °C extrusion and subsequently 200 °C-60 h peak aging process. Ultra-high strength can be attributed to its strong extrusion texture in stretched coarse grains and dispersed nano-scale precipitates. This unique bimodal structure could be produced easily by one step extrusion, which is quite reliable and low costs in industrial applications of magnesium alloys with ultra-high strength as well as ideal ductility.