Hot Deformation Behavior of a New Al-Mn-Sc Alloy.

Weiqi Kang,Hao Wang,Lei Li,Xi Zhang,Zhiqiang Cao,Yi Yang,Sheng Cao,Enquan Liang,Shewei Xin,Aijun Huang

doi:10.3390/ma13010022

Abstract

The hot deformation behavior of a new Al–Mn–Sc alloy was investigated by hot compression conducted at temperatures from 330 to 490 °C and strain rates from 0.01 to 10 s−1. The hot deformation behavior and microstructure of the alloy were significantly affected by the deformation temperatures and strain rates. The peak flow stress decreased with increasing deformation temperatures and decreasing strain rates. According to the hot deformation behavior, the constitutive equation was established to describe the steady flow stress, and a hot processing map at 0.4 strain was obtained based on the dynamic material model and the Prasad instability standard, which can be used to evaluate the hot workability of the alloy. The developed hot processing diagram showed that the instability was more likely to occur in the higher Zener–Hollomon parameter region, and the optimal processing range was determined as 420–475 °C and 0.01–0.022 s−1, in which a stable flow and a higher power dissipation were achieved.

Highlights

Casting and wrought aluminum (Al) alloys have been widely used as structural materials in aerospace industries owing to their high specific strength, excellent fatigue resistance, and good formability [1,2,3]
Cylindrical samples (φ10 × 15 mm) were sectioned by Electrical Discharge Machining (EDM) wire-cut from the ingot and ground by SiC abrasive sandpaper before subjecting to isothermal hot deformation experiments conducted on a Gleeble-3800 system
On the basis of dynamic material model (DMM), a hot conducted processing at map is established at a 0.4sstrain

Summary

Introduction

Casting and wrought aluminum (Al) alloys have been widely used as structural materials in aerospace industries owing to their high specific strength (strength to weight ratio), excellent fatigue resistance, and good formability [1,2,3]. The supersaturated Mn and Sc significantly improve the mechanical property through solid solution strengthening of Mn and precipitation strengthening of nano-sized Al3 Sc precipitates, which lead to a superior yield strength at 560 MPa and a good ductility at 18%. Such mechanical properties are attractive for aerospace industries. This Al–Mn–Sc alloy has only been studied in the additive manufactured condition, but has not been investigated in other forms like casting and wrought products

Methods

Results

Conclusion