The Evolution of Residual Stress and Microstructure in Shot Peened S30432 Austenitic Stainless Steel at High Temperatures

The thermal relaxation behavior of residual stress and microstructure at high temperatures in S30432 austenitic stainless steel after shot peening was investigated by X-ray residual stress analyzer. The effects of exposure time and applied temperature on the residual stress and microstructure relaxation were particularly analyzed and discussed. A significant decrease of the residual stress values were observed in the first period of exposure time, followed by slowing down and then stabilization. It was also observed that a higher applied temperature produced greater relaxation. In terms of microstructure, the domain size and micro-strain were calculated by Voigt method, the results showed that the refined domain size and high micro-strain induced by shot peening were greatly relaxed at the first stage of annealing, then stabilized. With higher annealing temperature, the recrystallization behavior in the shot peened deformed layer was more obvious. Based on the results of line profile analysis, the recrystallization activation energy and micro-strain relaxation energy were calculated, respectively.

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Relationship between Damping Factor and Compressive Residual Stress for Shot-Peened Austenitic Stainless Steel

ISRN Mechanical Engineering ◽

10.5402/2011/867484 ◽

2011 ◽

Vol 2011 ◽

pp. 1-7

Author(s):

Lakhwinder Singh ◽

R. A. Khan ◽

M. L. Aggarwal

Keyword(s):

Mechanical Properties ◽

Residual Stress ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Shot Peening ◽

Compressive Residual Stress ◽

Film Surface ◽

Damping Factor ◽

Thin Film Surface ◽

Deformed Layer

The mechanical properties of austenitic stainless steel are rarely improved by heat treatment. Shot peening is a well-known cold working process that affects thin surface of materials. By controlling the shot peening intensity and shot size, the variable mechanical properties film thickness was obtained from 0.05 mm to 0.5 mm. The damping factor and compressive residual stress are determined experimentally and forming a relation between them. It was found that damping factor in thin film surface increases with depth of deformed layer. An investigation was carried out, and it was found that the increase in damping factor was due to introduction of compressive residual stress and increased hardness due to shot peening. The paper discusses a model of changing damping properties with compressive residual stress and depth of deformed layer of austenitic stainless steel.

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The Influence of Shot Peening Process on the Residual Stress and Microstructure in Deformed Surface Layer of S30432 Austenitic Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.768-769.550 ◽

2013 ◽

Vol 768-769 ◽

pp. 550-556 ◽

Cited By ~ 2

Author(s):

Ke Zhan ◽

Chuan Hai Jiang ◽

Henry Pan

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Surface Layer ◽

Austenitic Stainless Steel ◽

Shot Peening ◽

Compressive Residual Stress ◽

Diffraction Method ◽

Micro Structure ◽

Near Surface ◽

Deformed Layer

Shot peening is an important surface treatment which can induce compressive residual stress and refine micro-structure in the deformed surface layer. In this paper, the conventional shot peening, dual shot peening and triple shot peening have been applied to S30432 austenitic stainless steel. The residual stress and micro-structure in the deformed layer were investigated by X-ray diffraction method. The results revealed that a compressive residual stress field was induced in the deformed layer for all shot peening conditions. As the shot peening step increased, the compressive residual stresses increased in near surface layer, and then deceased faster in deeper deformed layer. In terms of microstructure, the domain size increased, while the micro-strain decreased with the depth increasing in the deformed layer. Compare with the effect of three different shot peening method, triple shot peenng is more effective to optimize the compressive residual stress, microstructure and micro-hardness of S30432 austenitic stainless steel.

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Residual Stress Distribution and Microstructure Characterization of Particle Reinforced Titanium Matrix Composite after shot Peening Treatment: A Review

Current Nanoscience ◽

10.2174/1573413716999201012192606 ◽

2020 ◽

Vol 16 ◽

Author(s):

Yan Wen ◽

Yaya Wu ◽

Pu Liu ◽

Lechun Xie ◽

Weijie Lu

Keyword(s):

Residual Stress ◽

Dislocation Density ◽

Shot Peening ◽

Rietveld Method ◽

Thermal Relaxation ◽

Domain Size ◽

Strengthening Mechanism ◽

Relaxation Mechanism ◽

Titanium Matrix ◽

Avrami Model

Abstract: Shot peening (SP) can modify the surface properties of titanium alloys and titanium matrix composites (TMCs). Based on our previous work in the last ten years, the microstructure and mechanical properties of SP treated Ti-6Al-4V (TC4) and (TiB+TiC)/TC4 were summarized in this review. The compressive residual stress (CRS) was formed on surface after SP. At different SP intensities, the thickness of the surface CRS layer was improved with increasing SP intensities. During the stress peening, the CRS increased obviously, and the increment was proportional to the pre-stress. The thermal relaxation of CRS was investigated, and the CRS in the whole deformation layer was relaxed. The relaxation mechanism could be explained by Zener-Wert-Avrami model. The microstrain, the domain size, and the dislocation density of the peened layer were investigated using the Voigt method. The domain size of TC4 was smaller than that of composite, and the microstrain of TC4 was bigger than that of the composite. The average dislocation density was improved after SP, which was caused by the effect of SP and the existence of reinforcements. Utilizing the Rietveld method to analyze the microstructure after SP, the variations were similar to the results obtained by the Voigt method. The results indicated that the thermal stability of composite was higher than that of TC4 because of the existence of reinforcements. According to the hardness of peened layer, that of the surface was maximum, then decreased with the increase of depth. At the same temperature, the hardness of TC4 was smaller than that of the composite. Because the existence of reinforcements improved the hardness. The strengthening mechanism of SP was discussed and summarized based on above analysis.

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Uniformity of residual stress distribution on the surface of S30432 austenitic stainless steel by different shot peening processes

Materials Letters ◽

10.1016/j.matlet.2012.08.147 ◽

2013 ◽

Vol 99 ◽

pp. 61-64 ◽

Cited By ~ 44

Author(s):

K. Zhan ◽

C.H. Jiang ◽

V. Ji

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Stress Distribution ◽

Shot Peening ◽

Residual Stress Distribution

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Residual Stress Evaluation In Austenitic Stainless Steel Butt Weld Joints By Ultrasonic Technique

Indian Welding Journal ◽

10.22486/iwj.v25i3.148302 ◽

1992 ◽

Vol 25 (3) ◽

pp. 130 ◽

Cited By ~ 1

Author(s):

P. Palanichamy ◽

A. Joseph ◽

K. V. Kasiviswanathan ◽

D. K. Bhattacharya ◽

Baldev Raj

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Ultrasonic Technique ◽

Butt Weld ◽

Stress Evaluation ◽

Weld Joints

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Residual Stress Evaluation of Ni Based Weld Metal Using Neutron Diffraction Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.524-525.697 ◽

2006 ◽

Vol 524-525 ◽

pp. 697-702 ◽

Cited By ~ 1

Author(s):

Shinobu Okido ◽

Hiroshi Suzuki ◽

K. Saito

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Austenitic Stainless Steel ◽

Neutron Diffraction ◽

Weld Metal ◽

Diffraction Method ◽

Fem Analysis ◽

Butt Weld ◽

Stress Evaluation ◽

Neutron Diffraction Method

Residual stress generated in Type-316 austenitic stainless steel butt-weld jointed by Inconel-182 was measured using a neutron diffraction method and compared with values calculated using FEM analysis. The measured values of Type-316 austenitic stainless steel as base material agreed well with the calculated ones. The diffraction had high intensity and a sharp profile in the base metal. However, it was difficult to measure the residual stress at the weld metal due to very weak diffraction intensities. This phenomenon was caused by the texture in the weld material generated during the weld procedure. As a result, this texture induced an inaccurate evaluation of the residual stress. Procedures for residual stress evaluation to solve this textured material problem are discussed in this paper. As a method for stress evaluation, the measured strains obtained from a different diffraction plane with strong intensity were modified with the ratio of the individual elastic constant. The values of residual stress obtained using this method were almost the same as those of the standard method using Hooke’s law. Also, these residual stress values agreed roughly with those from the FEM analysis. This evaluation method is effective for measured samples with a strong texture like Ni-based weld metal.

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