摘要
The effect of the burn off rate on the structure and mechanical properties in the friction welded joint of low alloy constructional steel 35CrMo is studied in this paper. The results show that the increase in the burn off rate and deceleration time of friction welding can improve the toughness of the weld. The mechanism of improving the toughness of the weld is the finer grain size and the lower hardness of the weld. In this paper the microstructure of the joint is also analysed . The fine granular structure in the area near the weld has been studied by TEM.The results indicate that the strengthening mechanism of the weld metal is the high density of dislocation, a number of second island phases and fine grain size. By means of measuring the carbon content of the area near the weld, the effect of the burn off rate on the highest heating temperature of friction welding has also been investigated.
研究了变形速率对低合金结构钢 3 5CrMo磨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 .通过测试异种金属焊缝界面近区碳浓度的分布 ,探讨变形速率对磨擦焊最高加热温度的影响 。
