Damage prediction of 7025 aluminum alloy during equal-channel angular pressing

• Published in: International journal of minerals, metallurgy and materials metallurgy and materials, 2014-10, Vol.21 (10), p.990-998
• Main Authors: Ebrahimi, M., Attarilar, Sh, Gode, C., Djavanroodi, F.
• Format: Article
• Language: English
• Subjects: Aluminum; Aluminum alloys; Aluminum base alloys; Ceramics; Channels; Characterization and Evaluation of Materials; Chemistry and Materials Science; Coefficient of friction; Composites; Corrosion and Coatings; Cracks; Damage; Deformation; Deformation analysis; ECAP; Equal channel angular pressing; Finite element method; Friction; Glass; Grain refinement; Materials Science; Mathematical analysis; Mechanical properties; Metallic Materials; Natural Materials; Plastic deformation; Strain; Surface cracks; Surfaces and Interfaces; Thin Films; Tribology; Ultimate tensile strength; 应变行为; 挤压; 极限抗拉强度; 转角; 通道; 铝合金; 震害预测
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-014-1000-z

Equal-channel angular pressing （ECAP） is a prominent technique that imposes severe plastic deformation into materials to en- hance their mechanical properties. In this research, experimental and numerical approaches were utilized to investigate the mechanical prop- erties, strain behavior, and damage prediction of ECAPed 7025 aluminum alloy in various conditions, such as die channel angle, outer comer angle, and friction coefficient. Experimental results indicate that, after the first pass, the yield strength, ultimate tensile strength, and hardness magnitude are improved by approximately 95%, 28%, and 48.5%, respectively, compared with the annealed state, mainly due to grain re- finement during the deformation. Finite element analysis shows that the influence of die channel angle is more important than that of outer comer angle or friction coefficient on both the strain behavior and the damage prediction. Also, surface cracks are the main cause of damage during the ECAP process for every die channel angle except for 90°; however, the cracks initiated from the neighborhood of the central re- gions are the possible cause of damage in the ECAPed sample with the die channel angle of 90°.