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电子束焊接及局部热处理复合技术是一种多功能的电子束加工技术.文中以ANSYS有限元分析软件为平台,对2,6和12 mm厚的TC4钛合金平板电子束焊接和局部热处理时的温度场和应力场进行了数值模拟计算,详细分析了局部热处理对不同厚度钛合金平板电子束焊接温度场和残余应力场的影响规律.结果表明,在给定的计算条件下,2 mm厚TC4钛合金平板的电子束局部热处理效果最好,电子束局部热处理后上表面距焊缝中心线4 mm的区域内冷却速度基本一致,纵向残余拉应力最大值由780 MPa降低到560 MPa,减小幅度达到28%. 相似文献
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采用小孔检测法研究了规格Φ406.4 mm×12.5 mm、钢级L415MB的HFW焊管残余应力的分布情况。试验结果表明,HFW焊管整体残余应力值较小,并且轴向残余应力大于环向残余应力,轴向和环向最大值分别约为母材屈服强度的38%和29%;HFW电阻焊焊缝及其附近区域的残余应力值低于管体区域,轴向和环向残余应力的变化范围分别约为母材屈服强度的24.5%~33.6%和16.4%~21.5%;HFW电阻焊管轴向和环向残余应力的差异呈周期性变化,距离焊缝15°附近时差异最小。试验结果对于HFW电阻焊管在长输管线的应用提供理论支持。 相似文献
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采用小孔法测定了14.5mm厚TC4钛合金平板电子束焊接,研究了电子束焊接和局部热处理集成加工工艺下残余应力的分布,分析了局部热处理对焊接接头残余应力分布特征的影响.结果表明,在实验条件下电子束局部热处理后纵向残余拉应力的分布区间由焊接状态下焊缝中心线两侧距焊缝中心线5mm的区域减小到2mm的区域,纵向残余拉应力峰值同焊接状态相比降低了76%,横向残余压应力峰值降低了65%.电子束局部热处理未扫描的母材区域,残余应力数值同焊接状态相比几乎没有变化. 相似文献
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In general, the weld thermal cycle results in significant changes in microstructure and mechanical properties of the weld heat affected zone ( HAZ) . The microstructure, microhardness and low temperature impact toughness of HAZ for X100 pipeline steel were studied by means of welding thermal simulation. Influence of cooling time on the microstructure and properties in coarse-grained heat affected zone ( CGHAZ) was investigated. The results illustrated that polygonal ferrite and a small amount of granular bainite were obtained when the cooling time t 8/5 is larger than 1 500 s. Mainly granular bainite was formed when the cooling time t 8 / 5 is in the range of 1 500 s to 100 s. Bainite ferrite was observed when the cooling time is smaller than 60 s. Martensite appeared in the CGHAZ with the 20 s cooling time. The value of microhardness in the CGHAZ was higher than that of base metal ( BM) when the cooling time t 8/5 is smaller than 100 s. The CVN absorbed energy in the CGHAZ was higher than the value of BM when the cooling time t 8/5 is smaller than 30 s 相似文献