钛合金厚板焊接接头残余应力测试

采用局部逐层对称剥削材料盲孔法对51 mm厚钛合金Ti80板焊接接头残余应力进行了测试，并系统研究了其三维残余应力分布特征。结果表明，局部逐层剥削材料盲孔法能有效测量大厚度焊接件焊接接头的内部残余应力，并能准确反映大梯度变化应力状态。钛合金焊接接头，沿垂直焊缝方向在距焊缝中心-10~10 mm范围内，具有较高拉应力，应力值集中在500 MPa左右，且拉应力峰值出现在上表面距离焊缝中心10 mm位置；沿厚度方向距焊缝中心-10~10 mm范围内，为拉应力，表层应力普遍大于内部应力。在远离焊缝位置沿厚度方向为压应力，应力值为200~680 MPa，且峰值出现在距离上表面5 mm和焊缝中心20 mm位置处。

Residual Stress Test of Welded Joints of Titanium Alloy Thick Plates

The residual stress of the welded joint of 51 mm thick titanium alloy Ti80 plate was tested by the blind hole method of local layer-by-layer symmetric stripping material, and the three-dimensional residual stress distribution characteristics were systematically studied. The results show that the blind hole method of local layer-by-layer symmetric stripping material can effectively measure the internal residual stress of welding joint of large thickness welding joint and accurately reflect the state of large gradient change stress. The welded joints of titanium alloy have a high tensile stress in the direction of the vertical weld in the range of -10~10 mm from the center of the weld. The stress value is concentrated at about 500 MPa, and the tensile stress peak appears on the upper surface from the center of the weld 10 mm. In the thickness direction from the center of the weld to the range of -10~10 mm, the tensile stress is generally greater than the internal stress.The compressive stress is in the thickness direction away from the weld position, the stress value is between 200 and 680 MPa, and the peak appears at a distance of 5 mm from the upper surface and 20 mm from the center of the weld.