12th International Conference on Magnesium Alloys and their Applications (Mg 2021): Wrought Alloys III
Program Organizers: Alan Luo, Ohio State University; Mihriban Pekguleryuz, McGill University; Sean Agnew, University of Virginia; John Allison, University of Michigan; Karl Kainer; Eric Nyberg, Kaiser Aluminum Trentwood; Warren Poole, University of British Columbia; Kumar Sadayappan, CanmetMATERIALS; Bruce Williams, Canmetmaterials Natural Resources Canada; Stephen Yue, Mcgill University
Thursday 9:50 AM
June 17, 2021
Room: Invited IV
Location: Virtual
Session Chair: Zisheng Zhen, Magontec Asia
9:50 AM Invited
How Useful is Grain Refinement for Improving the Ductility of Magnesium Alloys?: Matthew Barnett1; 1Deakin University
This presentation discusses the failure of magnesium alloy AZ31 during tension, compression and bending. The aim is to determine how useful grain refinement is for extending the room temperature ductility. The ductility of a series of test samples is examined using X-ray microtomography. Using this approach enabled us to characterize void nucleation, growth and linkage during tensile loading. We conclude the impact of grain size on void growth is the critical factor. Voids grow faster in coarse grained samples and this hastens failure. The mechanism seems unique to tension and so some statements can be made regarding the impact of grain size on other deformations. The extent to which the conclusions can be generalized is also considered.
10:20 AM Invited
Microstructure and Mechanical Properties of Ultrahigh-strength Low-alloy Mg-Al-Ca-Mn Extrusion Alloys: Mingyi Zheng1; X.Q. Liu1; Z.T. Li1; X.G. Qiao1; 1Harbin Institute of Technology
The development of high-strength wrought magnesium alloys are mostly based on strengthening from second phases. However, high number density of second phases reduces ductility and formability of Mg alloys. We developed new ultrahigh-strength low-alloy Mg-Al-Ca-Mn extrusion alloys by taking full advantage of fine-grain strengthening induced by ultrafine grains and grain boundary segregation-induced strengthening. The composition and extrusion parameters on microstructure and mechanical properties of low-alloy Mg-Al-Ca-Mn alloys were investigated. A Mg-1Al-1Ca-0.4Mn (wt%) alloy extruded at 200oC and extrusion rate of 1.5 mm/s exhibited TYS of 412 MPa, UTS of 419 MPa and elongation to failure of 12.0%, while a Mg-0.7Al-0.3Ca-0.4Mn (wt%) alloy extruded at 200oC and extrusion rate of 1.0 mm/s exhibited TYS of 412 MPa, UTS of 418 MPa and elongation to failure of 14.8%. The mechanism of microstructural evolution and strengthening mechanism of the ultrahigh-strength-low-alloy Mg-Al-Ca-Mn alloys were discussed.