Prof. Qinghuan Huo
Central South University, China
Title: Comprehensive study on the creep behavior of Mg-RE binary alloys
Abstract:
The compressive creep behaviors were systematically studied on a pure Mg (0Y alloy) and various Mg-Y binary alloys (0.15Y, 1.5Y, 4.5Y, 7.5Y and 10.5Y alloys) at 523 K under various applied stresses. The loading directions were carried out parallel to rolling direction (RD), transverse direction (TD) and normal direction (ND), respectively. It was shown that the creep behaviors exhibited obvious dependence on loading direction in 0Y, 0.15Y, 1.5Y and 4.5Y alloys. The creep resistance had a sequence of ND > TD ≥ RD in these alloys. Their creep anisotropy was caused by cross-slip and twinning dominating the creep along RD and TD while dislocation climb and pyramidal <c+a> slip prevailing along ND. Compared to 0Y, 0.15Y and 1.5Y alloys, the more random basal texture weakened cross-slip and twinning along RD and TD and aroused cross-slip along ND, resulting in the decreased creep anisotropy in 4.5Y alloy. Inversely, 7.5Y and 10.5Y alloys showed a nearly creep isotropy due to cross-slip and pyramidal <c+a> slip dominated the creep along all three loading directions. Moreover, compared to 0Y alloy, the creep resistance was found to be slightly increased in 0.15Y alloy and significantly increased with increasing Y content above 1.5wt%. It was attributed to that solution strengthening and pyramidal <c+a> dislocations collaboratively increased the creep resistance. The improved hindering effect on twinning was also helpful to increase the creep resistance along RD and TD. Besides, dynamic precipitation strengthening assisted the increment of creep resistance in 10.5Y alloy. Thus, the addition of concentrated Y element in Mg alloys is a valid solution to eliminate the compressive creep anisotropy and simultaneously enhance the creep resistance.
Keywords: Magnesium alloy; Mechanical behavior; Microstructure; Deformation mechanism; Heat treatment.
Biography:
The major research fields are microstructure
characterization, plastic processing, mechanical behaviors of light metals such
as Mg alloys and Al alloys. Over 60 academic
papers (First Author and Corresponding Author)
have been published in the journals ranking in JCR Q1.
The
work experience is here:
03/2018
– Present: Central South University, China
Major:
Materials Science and Engineering
Position:
Associate Professor
10/2017
– 03/2018: Tohoku University, Japan
Major:
Materials Science
Position:
Researcher
The
education experience is here:
10/2014
– 09/2017: Tohoku University,
Japan
Major:
Materials Science
Degree:
Doctor of Engineering
09/2011
– 12/2013: Central South University, China
Major:
Materials Science and Engineering
Degree:
Master of Engineering
09/2007
– 06/2011: Central South University, China
Major:
Materials Science and Engineering
Degree: Bachelor of Engineering