Work-softening behavior of the ultrafine-grained Al alloy processed by high-strain-rate, dissimilar-channel angular pressing

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Vol. 34; no. 3; pp. 625 - 632
• Main Authors: LEE, Jae-Chul, SUH, Jin-Yoo, AHN, Jae-Pyung
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01.03.2003; Springer Nature B.V
• Subjects: Alloys; Applied sciences; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Metallurgy; Metals. Metallurgy; Other heat and thermomechanical treatments; Physics; Treatment of materials and its effects on microstructure and properties; Aluminium base alloys; Electron diffraction; Mechanical properties; Plastic deformation; Experimental study; Silicon additions; Transmission electron microscopy; Pressing; Fine grain structure; Thermomechanical treatments; Iron additions; Microstructure; Strain rate
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-003-0097-x

Commercially pure Al alloy sheets were processed using high-strain-rate, dissimilar-channel angular pressing (DCAP) for as many as 100 passages through a channel with ? = 120 deg, to investigate the work hardening caused by a low strain level (ε < 2) and the work softening caused by an extremely high strain level (3 < ε < 58). The hardness of the alloy increased significantly by a factor of 2 at strains less than ~2, while a gradual decrease in the hardness was observed at strains greater then ~2. The work-hardening and the work-softening behaviors observed from the Al alloy were analyzed by correlating the measured properties with microstructural evolutions observed by transmission electron microscopy (TEM). A detailed microstructural-evolution sequence occurring at successive strain stages was also investigated based on TEM and electron backscattered diffraction (EBSD).