Strain Heterogeneity induced by Multi-Axial Compression (MAC) processing

M. E. L. NASSIF; C. G. FARIA; P. M. A. STEMLER; N. G. S. ALMEIDA; DE CASTRO BUBANI, FRANCO; M. T. P. AGUILAR; P. R. CETLIN

Bariloche

Simposio; XXIII Latin American Symposium on Solid State Physics; 2018

Severe Plastic Deformation (SPD) has been used as a grain refinement technique reaching submicrometer scale owing to the excellent mechanical and functional properties exhibited by the ultra-fine grained (UFG) materials [1]. The most studied SPD techniques are High Pressure Torsion (HPT), Equal Channel Angular Pressing (ECAP) and Multi-Axial Compression (MAC) [2]. MAC stands out among these techniques because it is possible to evaluate the mechanical behavior evolution during the processing, and it is easy to process. In addition, large specimens can be processed, allowing its application as an industrial process. However, MAC induces strain heterogeneity in the material, which leads to different mechanical behaviors throughout the specimen. In the present research MAC was applied to pure Aluminum (99,77%) under constrained deformation and the strain distribution after processing was evaluated through microhardness maps. MAC processing induces larger strains in the center and along the diagonals of the specimens, probably associated with the friction between the anvils and the specimen and the restraining effect of the die walls.[1] KUMAR, S.S.; PRIYASUDHA, K.; RAO, M.S.; RAGHU, T. Deformation homogeneity, mechanical behavior and strain hardening characteristics of titanium severe plastically deformed by cyclic channel die compression method. Materials & Design, v. 101, p. 117 (2016)[2] FARIA, C.G.; ALMEIDA, N. G. S.; AGUILAR, M.T. P.; CETLIN, P. R. Increasing the work hardening capacity of equal channel angular pressed (ECAPed) aluminum through multi-axial compression (MAC). Materials Letters, v. 174, p. 153 (2016).