Hot Deformation Treatment of Grain-Modified Mg-Li Alloy.

Mariusz Król,Marek Pagáč,Przemysław Snopiński,Jana Petrů,Jiří Hajnyš

doi:10.3390/ma13204557

Mariusz Król, Marek Pagáč + Show 3 more

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https://doi.org/10.3390/ma13204557

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Abstract

In this work, a systematic analysis of the hot deformation mechanism and a microstructure characterization of an as-cast single α-phase Mg–4.5 Li–1.5 Al alloy modified with 0.2% TiB addition, as a grain refiner, is presented. The optimized constitutive model and hot working terms of the Mg–Li alloy were also determined. The hot compression procedure of the Mg–4.5 Li–1.5 Al + 0.2 TiB alloy was performed using a DIL 805 A/D dilatometer at deformation temperatures from 250 °C to 400 °C and with strain rates of 0.01–1 s−1. The processing map adapted from a dynamic material model (DMM) of the as-cast alloy was developed through the superposition of the established instability map and power dissipation map. By considering the processing maps and microstructure characteristics, the processing window for the Mg–Li alloy were determined to be at the deformation temperature of 590 K–670 K and with a strain rate range of 0.01–0.02 s−1.

Highlights

Magnesium–lithium ultra-light alloys, as a very light structure metal, have a low density, high specific strength and stiffness, good damping performance, and excellent formability [1,2,3]
Numerous studies have been completed on the hot deformation behavior with duplex structured Mg–Li alloys; there is a dearth of research performed on single α(Mg) phase Mg–Li alloys
An accurate processing flow thethe deformation temperature and strain rate, and they indicated constitutive rangestress can correlated be selectedtoon basis of zones that are characterized with a low η anda are without model analysis and thermal processing map of the Mg–4.5 Li–1.5 Al + 0.2 TiB alloy

Summary

Introduction

Magnesium–lithium ultra-light alloys, as a very light structure metal, have a low density, high specific strength and stiffness, good damping performance, and excellent formability [1,2,3]. Numerous studies have been completed on the hot deformation behavior with duplex structured Mg–Li alloys; there is a dearth of research performed on single α(Mg) phase Mg–Li alloys. Establishing a constitutive model is a popular and essential way to characterize the deformation behavior of metal structured materials at various strains, strain rates, and temperatures. Hot compression tests on single α-phase as-cast Mg–4.5 Li–1.5 Al alloy with an HCP structure and with TiB addition as a grain refiner to further improve the strength were used to systematically analyze the deformation behavior of the alloy at elevated temperatures. The optimized constitutive model and hot working terms of the Mg–Li alloy with TiB were established

Materials and Methods

Results and Discussion

To get the

Conclusion