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研究了变形速率对低合金结构钢３５ＣｒＭｏ摩擦焊接头组织与力学性能的影响。结果表明，增加变形速率可改善焊缝韧性。焊缝韧性改善的机理为近缝区晶粒细化和硬度降低。采用金相法、ＴＥＭ法对近缝区粒状组织精细结构进行了观察，粒状组织小岛是由Ｍ－Ａ组成。指出增加变形速率使近缝区金属强化机制为位错强化、一定数量的岛状第二相强化和细晶粒强化。本文通过测试异种金属焊缝界面近区碳浓度的分布，探讨了变形速率对摩擦焊最高加热温度的影响，增加变形速率可使摩擦界面的最高加热温度下降。
The effect of deformation rate on the microstructure and mechanical properties of 35CrMo friction stir welded low alloy steel was studied. The results show that increasing the deformation rate can improve the weld toughness. The mechanism of weld toughness improvement is grain refinement and hardness reduction in the near-seam area. The fine structure of granular tissue near the seam was observed by metallographic method and TEM method. The granular tissue island was composed of M-A. It is pointed out that increasing the deformation rate makes the strengthening mechanism of near-seam metal as dislocation strengthening, a certain number of island-like second phase strengthening and fine grain strengthening. In this paper, the influence of deformation rate on the maximum heating temperature of friction welding was discussed by testing the distribution of carbon concentration in the vicinity of the dissimilar metal weld interface. The maximum heating temperature of the friction interface was decreased by increasing the deformation rate.