The in-depth residual strain heterogeneities due to an indentation and a laser shock peening for Ti-6Al-4V titanium alloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:714

Article

Xie, Q.¹  Li, R.¹  Wang, Y. D.¹  Su, R.²  Lian, J.³  Ren, Y.⁴  Zheng, W.¹  Zhou, X.⁵  Wang, Y.⁶ 

[1] Univ Sci & Technol Beijing, State Key Lab Adv Met & Mat, Beijing 100083, Peoples R China

[2] Beijing Inst Technol, Sch Mat Sci & Engn, Beijing 100081, Peoples R China

[3] Rhein Westfal TH Aachen, Steel Inst, Intzestr 1, D-52072 Aachen, Germany

[4] Argonne Natl Lab, Xray Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA

[5] Air Force Engn Univ, Sci & Technol Plasma Dynam Lab, Xian 710038, Shanxi, Peoples R China

[6] Beijing Inst Aeronaut Mat, Beijing 100095, Peoples R China

关键词: Laser shock peening;    Indentation;    Ti-6Al-4V;    Residual strains;    Elastic-visco-plastic finite element model;   

DOI  :  10.1016/j.msea.2017.12.073

来源: Elsevier

【 摘 要 】

Heterogeneity of the through-thickness residual strain due to the laser shock peening (LSP) in comparison with that due to the indentation was studied in Ti-6Al-4V alloy samples. The latter is almost a quasi-static process while the former features extremely high strain-rate deformation. The synchrotron based high-energy X-ray diffraction was employed to investigate the through-thickness residual strain distribution. The studied two samples after the two processing procedures share the following features: (i) the pressure affected depths are both similar to 2 mm and (ii) the largest magnitudes of the compressive residual strains parallel to the surface are similar to 4,000 mu epsilon. However, the pit depth for the indentation sample is similar to 9 times larger than that for the LSP. The position featuring the largest magnitude of the compressive residual strain is in the sub-surface for the indentation while it is in the surface for the LSP. Results of the elastic-visco-plastic finite element simulation for the indentation indicate that the position featuring the maximum accumulative plastic shear as defined in this paper corresponds to the location with the largest magnitude of compressive residual strain. To validate this finding, full width at half maximum (FWHM) of the X-ray diffraction profile, which is proportional to the level of the plastic deformation, is also studied. It is found that positions with the largest FWHM indeed correspond to the largest magnitude of compressive residual strain for both tests.

【 授权许可】

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