Stability of residual stress induced by laser peening under cyclic mechanical loading

Abstract

PurposeThe purpose of this paper is to investigate the behavior of compressive residual stress induced by laser peening under external loading on an age‐hardened high‐strength aluminum alloy A2024‐T3, a low‐carbon austenitic stainless steel SUS316L (Type 316L) and a nickel‐based alloy NCF600 (Alloy 600).Design/methodology/approachThe surface residual stress was measured intermittently by X‐ray diffraction during cyclic uniaxial loading.FindingsThe compressive residual stress due to laser peening significantly decreased during the first few cycles at stress ratio of 0.1 with the maximum loading stress exceeding the 0.2 per cent yield stress. No remarkable decrease was observed afterward until the end of the loading cycles.Originality/valueUnder symmetric loading at the stress ratio of −1 to A2024‐T3, a major decrease took place in the compression side of the first loading cycle. The surface residual stresses remained in compression within all the extent of the present experiments, even if the maximum loading stress exceeded the yield stress of the materials.

Effect of low-temperature surface hardening by carburization on the fatigue behavior of AISI 316L austenitic stainless steel

“…Conventionally, the relaxation of the surface compressive residual stresses introduced by mechanical surface treatments like deep rolling [19] or laser penning [26] are successively lower and mainly take place during the first cycle followed by incrementally reducing changes during further cyclic loading. Interestingly, the compressive residual stresses introduced by low-temperature carburization appear to be more stable under the cyclic loading than those induced by deep rolling or laser penning.…”

Laser shock peening without absorbent coating (LSPwC) effect on 3D surface topography and mechanical properties of 6082-T651 Al alloy

“…As a result, high compressive residual stresses are generated and confined to a shallow surface layer whilst balancing low-tensile residual stresses are spread deeper throughout the cross-section of the material [12], Enhancement of fatigue, corrosion, stress corrosion and wear resistance has already been proved for various types of materials, such as aluminium and titanium alloys and different types of steel [11][12][13][14][15][16][17][18]. In our recent publication [18], we investigated the effect of LSPwC treatment on corrosion behaviour on an AA6082 aluminium alloy in a 0.6 M NaCI solution.…”

Study on the Changing Law of Cutting and Ultrasonic Strengthening Surface Integrity during Fatigue of Ti-17 Alloy

“…Under room temperature and low cycle fatigue conditions, the residual stress relaxation degree is less than 50% of the peak residual stress. In comparison, the maximum residual stress relaxation degree can reach 70% of the peak value of the residual stress at high temperatures [14].…”