Improving Significantly the Failure Strain and Work Hardening Response of LPSO-Strengthened Mg-Y-Zn-Al Alloy via Hot Extrusion Speed Control

Xinghe Tan; Winston Chee; Jimmy Chan; Richard Kwok; Manoj Gupta

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자료유형: 학술저널

저자정보: Xinghe Tan (Singapore Technologies Kinetics Ltd (ST Kinetics)) Winston Chee (Singapore Technologies Kinetics Ltd (ST Kinetics)) Jimmy Chan (Singapore Technologies Kinetics Ltd (ST Kinetics)) Richard Kwok (Singapore Technologies Kinetics Ltd (ST Kinetics)) Manoj Gupta (National University of Singapore)

저널정보: 대한금속·재료학회 Metals and Materials International Metals and Materials International Vol.23 No.4

발행연도: 2017.1

수록면: 699 - 707 (9page)

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The effect of hot extrusion speed on the microstructure and mechanical properties of MgY1.06Zn0.76Al0.42 (at%)alloy strengthened by the novel long-period stacking ordered (LPSO) phase was systematically investigated. Increase in the speed of extrusion accelerated dynamic recrystallization of α-Mg via particle-stimulated nucleationand grain growth in the alloy. The intensive recrystallization and grain growth events weakened the conventionalbasal texture and Hall-Petch strengthening in the alloy which led to significant improvement in its failure strainfrom 4.9% to 19.6%. The critical strengthening contribution from LPSO phase known for attributing high strengthto the alloy was observed to be greatly undermined by the parallel competition from texture weakening and theadverse Hall-Petch effect when the alloy was extruded at higher speed. Absence of work hardening interestinglyobserved in the alloy extruded at lower speed was discussed in terms of its ultra-fine grained microstructure whichpromoted the condition of steady-state defect density in the alloy; where dislocation annihilation balances out thegeneration of new dislocations during plastic deformation. One approach to improve work hardening response ofthe alloy to prevent unstable deformation and abrupt failure in service is to increase the grain diameter in the alloyby judiciously increasing the extrusion speed.

참고문헌 (27)

참고문헌 신청

2014 / SAE Standard AIR 6160, Magnesium Alloys in Aircraft Seats -Developments in Magnesium Alloy Flammability Testing / SAE International

2005 / SAE Standard AS8049B, Performance Standard for Seats in Civil Rotorcraft, Transport Aircraft, and General Aviation Aircraft / SAE International

FAA / Oil Burner Flammability Test for Magnesium Alloy Seat Structure

F. Czerwinski / 2014 / Corros. Sci 86:1

A. Stachel / Light Weight Alloys in Seat Design, Influence of Magnesium in Seats