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Dean Deng - One of the best experts on this subject based on the ideXlab platform.

  • Investigation of welding Residual Stress Distribution in a thick-plate joint with an emphasis on the features near weld end-start
    Materials and Design, 2015
    Co-Authors: Wei Liang, Hidekazu Murakawa, Dean Deng
    Abstract:

    In this study, an advanced computational approach with considering moving heat source, temperature-dependent material properties, strain-hardening and annealing effect was developed to predict welding temperature field, Residual Stress Distribution and deformation in multi-pass welded joints. The welding Residual Stress Distributions in austenitic stainless steel thick-plate multi-pass joints performed by the different deposition patterns and different deposition directions were simulated through using the developed computational procedure. Based on the numerical results, the features of Residual Stress Distribution near the weld end-start location were examined. Meanwhile, experiments were carried out to measure the welding Residual Stress Distributions in two mock-ups. The numerical results are generally in a good agreement with the experimental measurements. Both experiment and numerical model show that the Distribution of welding Residual Stress near the weld end-start location has an apparent discontinuous feature. The research results indicate that deposition pattern has a significant influence on welding Residual Stress, and it not only can change the Distribution shape of Residual Stress but also can alter the peak value of Residual Stress. Under the condition of identical deposition pattern, the Distribution of welding Residual Stress seems not sensitive to deposition direction.

  • influence of deposition sequence on welding Residual Stress and deformation in an austenitic stainless steel j groove welded joint
    Materials & Design, 2013
    Co-Authors: Dean Deng
    Abstract:

    Abstract Residual tensile Stresses often increase the susceptibility to cold cracking, and also promote brittle fracture, fatigue failure, and Stress corrosion cracking in combination with tensile Stresses experienced during service. Welding-induced deformation usually degrades the performance of a structure. Thus, the control of welding Residual Stress and distortion is a crucial task in welding manufacturing. There are too many factors that affect welding Residual Stresses and distortion. Besides material properties and design-related parameters, the welding procedures such as deposition sequence and assembly sequence also have significant influence on the final Residual Stress Distribution and deformation. In this study, a computational approach based on Quick Welder software was developed to simulate the welding temperature field, Residual Stress Distribution and deformation in multi-pass joints. The main objective was to clarify the influence of deposition sequence on the final Residual Stress Distribution and deformation in an austenitic stainless steel tube–block joint with J-groove. The simulation results indicate that deposition sequence not only significantly affects the Distribution of Residual Stress but also can alter the deformation mode to a certain extent. In addition, it was found that the last weld pass seems to have the largest contribution to the final welding Residual Stress filed of current tube–block joint.

  • fem prediction of welding Residual Stresses in a sus304 girth welded pipe with emphasis on Stress Distribution near weld start end location
    Computational Materials Science, 2010
    Co-Authors: Dean Deng, Shoichi Kiyoshima
    Abstract:

    A finite element approach based on Quick Welder software is developed to simulate welding temperature field and welding Residual Stress Distribution in a 3D multi-pass girth-welded pipe model. The characteristics of welding Residual Stress Distributions in a SUS304 stainless steel pipe induced by heating with a tungsten inert gas arc welding torch are investigated numerically. Meanwhile, an emphasis is focused on examining the welding Residual Stress Distributions in and near the weld start/end location. Moreover, the Residual Stresses predicted by the present computational approach are compared with the measured data; and the comparison suggests that the numerical simulation method has basically captured the feature of welding Residual Stress Distribution near the weld start/end region. The numerical simulation results show that both the hoop and the axial Residual Stresses near the weld start/end region have sharp gradients and are significantly different from those in the steady range.

Neil M James - One of the best experts on this subject based on the ideXlab platform.

Chuanhai Jiang - One of the best experts on this subject based on the ideXlab platform.

  • numerical analysis and experimental validation on Residual Stress Distribution of titanium matrix composite after shot peening treatment
    Mechanics of Materials, 2016
    Co-Authors: Lechun Xie, Chengxi Wang, Liqiang Wang, Zhou Wang, Chuanhai Jiang
    Abstract:

    Abstract The Residual Stress Distribution introduced by shot peening (SP) in the deformed surface layer of titanium matrix composite (TiB+TiC)/Ti-6Al-4 V was investigated via three-dimensional (3D) finite element dynamic simulation and experimental validation. The program of ANSYS/LS-DYNA was utilized in the 3D finite element dynamic analysis of SP process, and the 3D homogeneous and inhomogeneous models were set up. The results showed that the compressive Residual Stresses (CRS) were introduced in the matrix, but the tensile Residual Stresses appeared in the reinforcements. The maximum CRS and tensile Residual Stress were -1511 and +1155 MPa respectively, which revealed the higher yield strength of reinforcements. This type of Stress Distribution revealed the effect of reinforcements, keeping the adverse tensile Stresses in the reinforcements and retarding the damage to the matrix during deformation. In terms of experiments, after SP, the Residual Stresses along the depth from the surface were measured using X-ray diffraction (XRD) method. The experimental results indicated that the CRS formed in the surface layer and the maximum appeared on the subsurface. The range of Residual Stresses found in experiments supported the simulated results, which verified the validity of 3D finite element dynamic analysis.

  • uniformity of Residual Stress Distribution on the surface of s30432 austenitic stainless steel by different shot peening processes
    Materials Letters, 2013
    Co-Authors: K Zhan, Chuanhai Jiang, Vincent Ji
    Abstract:

    Abstract Compressive Residual Stress induced by shot peening can effectively improve the fatigue resistance of the treated component. Much attention has been paid to increase the compressive Residual Stress value, and the uniformity of Residual Stress Distribution was often ignored, which was also very important for improving the fatigue resistance. In this paper, the uniformity of compressive Residual Stress Distributions on the surface of S30432 austenitic stainless steel after three different shot peening treatments has been investigated by X-ray diffraction method. The results revealed that compared with traditional shot peening, multi-step shot peening (dual shot peening, triple shot peening) methods can not only increase the Stress value but also make the Stress Distribution more uniform.

  • influence of shot peening on the fatigue life of laser hardened 17 4ph steel
    International Journal of Fatigue, 2011
    Co-Authors: Chuanhai Jiang, Yanhua Chen
    Abstract:

    In order to improve the fatigue life of 17-4PH steel after laser hardening treatment, shot peening and dual shot peening treatments were performed on laser hardened 17-4PH steel in this paper. Characteristic changes of the roughness, hardness and Residual Stress Distribution in three typical areas were discussed in order to gain a better understanding about the shot peening influence on laser hardened material state. Results showed that initial Residual Stresses had no influence on the finial Residual Stress Distribution in shot peening influence region after shot peening treatment. The fatigue life of laser hardened 17-4PH steel increased dramatically after shot peening treatment.

P J Withers - One of the best experts on this subject based on the ideXlab platform.

  • investigation of Residual Stress Distribution and texture evolution in aa7050 stationary shoulder friction stir welded joints
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2018
    Co-Authors: Tianzhu Sun, A S Tremsin, M J Roy, M Hofmann, P B Prangnell, P J Withers
    Abstract:

    Abstract A study of the Residual Stress Distribution and texture evolution in stationary shoulder friction stir welded (SSFSW) AA7050 plate through non-destructive energy-resolved neutron imaging (NI), monochromatic neutron diffraction (ND) and destructive contour method (CM) is described in this paper. The presence of Bragg edges in the neutron transmission spectra are shown to be effective in determining the longitudinal Residual Stress and compare well with results obtained by ND and CM. The texture in the weld zone and base metal has been mapped by contrast in the narrow-energy transmission image combined with an analysis of the Bragg edges in the transmission spectra at each pixel showing agreement with the results obtained by electron backscatter diffraction (EBSD) mapping. The ND results were complicated by plastic anisotropy effects in the rolled plate which meant that different reference Stress-free lattice spacings were required at each point in the 3 principal directions for this material. NI and CM were unaffected by texture effects in determining Residual Stress. Compared to conventional techniques, NI is shown to be an effective way of quantifying both texture and Residual Stress in one shot.

  • effects of tooling on the Residual Stress Distribution in an inertia weld
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2003
    Co-Authors: J W L Pang, P J Withers, M Preuss, G J Baxter, C Small
    Abstract:

    Abstract Neutron diffraction Residual strain measurements have been made on a tubular structure formed by joining two nickel-based superalloy RR1000 parts by inertia welding. Residual strains in the radial, hoop and axial directions of the tube cross-section have been measured. The corresponding Residual Stress field has been calculated accounting for the Stress-free lattice parameter variations in the region close to the weld line. Tensile Residual Stresses were observed near the inner diameter of the tube with magnitudes of the order of +500, +1100 and +1300 MPa in the radial, axial and hoop directions, respectively. By comparison near the outer diameter (OD) of the weld the corresponding Stresses are of the order of −200, −1000 and 150 MPa. The final Stress state reflects the influence of the gripping fixture tooling and thermal gradients during inertia welding. Additional X-ray (at the surface) and hole-drilling (at the near surface) measurements show a steep Residual Stress gradient in the near surface region. Tensile hoop and axial machining Stresses at the surface indicate the potential for improving the inertia weld tooling and the machining parameters used when removing the flash.

  • synchrotron x ray Residual strain scanning of a friction stir weld
    Journal of Strain Analysis for Engineering Design, 2001
    Co-Authors: P J Webster, P J Withers, Djapic L Oosterkamp, P A Browne, Darren J Hughes, W P Kang, G B M Vaughan
    Abstract:

    Synchrotron X-ray strain scanning has been used to determine the Residual Stress Distribution over the cross-sectional area of a friction stir weld across an I-section made of extruded aluminium al...

Filippo Berto - One of the best experts on this subject based on the ideXlab platform.