Reduction of residual stress in low alloy steel with magnetic treatment in different directions

2009 ◽  
Vol 24 (6) ◽  
pp. 857-862 ◽  
Author(s):  
Yanli Song ◽  
Lin Hua ◽  
Ben Wang
Keyword(s):  
Residual Stress ◽  
Alloy Steel ◽  
Magnetic Treatment ◽  
Low Alloy Steel

Study on Evaluation Procedure for Calculating the Stress Intensity Factor of Flaws Beneath RPV Cladding During Pressurised Thermal Shock Events by FE Analysis

2016 ◽  
Author(s):  
Hiroyuki Sakamoto ◽  
Takatoshi Hirota ◽  
Naoki Ogawa
Keyword(s):  
Residual Stress ◽  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Thermal Shock ◽  
Alloy Steel ◽  
Fe Analysis ◽  
Welding Residual Stress ◽  
Low Alloy Steel ◽  
Elastic Plastic

Elastic-plastic finite element (FE) analysis is performed to determine the plastic behavior of the reactor pressure vessel (RPV) inner surface caused by rapid cooling during pressurized thermal shock (PTS) events. However, as the J-integral is not path-independent for elastic-plastic material in the unloading process, it is necessary to apply a suitable correction method using elastic material. In addition, it is also necessary to consider the effect of the welding residual stress appropriately. Therefore, we investigated the stress intensity factor derived from FE analysis based on a model consisting of elastic-plastic cladding and linear elastic low-alloy steel with subsequent plastic zone correction, since the stress level of low-alloy steel remains within the elastic region except the crack front during a PTS event. Furthermore, we examined whether the stress mapping method is applicable for reflecting the effect of welding residual stress in FE analysis, even though the plastic strain generated during welding is ignored.

Numerical Analysis of the Influence on High Humidity in a T-Joint Fillet Weld for High Strength Low Alloy Steel

2014 ◽  
Vol 651-653 ◽  
pp. 56-59
Author(s):  
Song Ping Chen ◽  
Yong Xian Li ◽  
Yan Ji Xie
Keyword(s):  
Residual Stress ◽  
Alloy Steel ◽  
Steel Structures ◽  
High Strength ◽  
Computational Procedure ◽  
Steel Plates ◽  
Transient Temperature ◽  
High Humidity ◽  
Low Alloy Steel ◽  
Port City

Welding at high humidity is frequently needed for the harbor hoisting machinery of steel structures in the coastal port city. A computational procedure is proposed for analyzing residual stress and temperature distributions induced by the T-joint welding in two types of St52-3 high strength low alloy steel plates both 6 mm in thickness. The relative humidity conditions varied from 75 to 90% at constant pressure. The finite element models are employed to evaluate the transient temperature and the residual stress during welding. According to the analysis results, the higher residual stress and the highest concentration of hydrogen are distributed in and surround the heat affected zone (HAZ), and vary with different humidity.

scholarly journals Influence of carbonitriding conditions on phase composition and residual stresses for 20MnCr5 low alloy steel

2021 ◽  
Vol 47 (2) ◽  
pp. 790-799
Author(s):  
Richard J Katemi ◽  
Jeremy Epp
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Alloy Steel ◽  
Retained Austenite ◽  
Case Depth ◽  
Martensite Phase ◽  
Stress Distributions ◽  
Low Alloy Steel ◽  
The Core ◽  
Core Hardness

This paper reports an investigation of the influence of carbonitriding conditions for 20MnCr5 low alloy steel. Three gaseous carbonitriding conditions were investigated based on different carbon and nitrogen potentials to attain varying levels of carbon between 0.62 and 0.93% mass, whereas for nitrogen between 0.19 and 0.26% mass at the surface. Analysis of retained austenite and residual stress distributions was conducted using X-ray diffraction technique. The effective case depth varied between 900 and 1200 µm. The case microstructures were characterized by varying proportions of retained austenite and martensite, while the core contained essentially bainitic microstructures. The maximum amount of retained austenite which occurred at a depth of 50 µm from the subsurface ranged between 30 and 70% mass and significantly influenced the level of surface micro-hardness whereas the core hardness remaining relatively constant at 450 HV1. High values of residual stresses in martensite phase were observed. The signs, magnitudes, distributions and location of maximum compressive residual stresses were highly influenced by the maximum fraction of retained austenite. Retained austenite of 30%, 50% and 70% mass at the surface lead to peak compressive residue stresses of -280, -227, and -202 MPa at depths of 555, 704, and 890 μm, respectively. Keywords: Carbonitriding, retained austenite, martensite, residual stress, XRD.

Sign in / Sign up

Export Citation Format

Share Document