基于材料流动轨迹的搅拌摩擦焊接晶粒及焊接区大小预测模型

发布时间：2018-04-15 02:21

本文选题：搅拌摩擦焊接 + 完全热力耦合模型　；参考：《机械工程学报》2015年02期

【摘要】：通过热力耦合模型模拟搅拌摩擦焊接过程中的材料行为,并基于材料的运动轨迹区分焊接区域中的搅拌区和热力影响区。给出热力影响区和搅拌区边界处流动轨迹上的真实应变率和温度历史曲线,进一步计算Zener-Holloman参数和搅拌区内的晶粒大小,通过与已有文献的对比验证计算结果的准确性。结果显示尽管应变率分布不均匀,均匀分布的温度使lg Z在搅拌区内均匀分布,这说明温度对搅拌区内晶粒大小变化的影响较应变率更为明显。绕针运动的物质点的应变率明显高于其他运动轨迹上的物质点的应变率,可以达到22 s 1。通过对不同材料流动行为的跟踪可以确定搅拌区和热力影响区的边界。搅拌区晶粒随搅拌头轴肩的增大而增大,且搅拌区尺寸随搅拌头轴肩的增大而增大。较小的搅拌头会使搅拌区的区域变小。
[Abstract]:The material behavior during friction stir welding is simulated by the coupled thermodynamic model, and the stir zone and the thermal affected zone are distinguished based on the material motion trajectory.The true strain rate and temperature history curves at the boundary of the thermal affected zone and the mixing zone are given. The Zener-Holloman parameters and the grain size in the mixing zone are further calculated. The accuracy of the calculated results is verified by comparison with the previous literatures.The results show that, although the strain rate distribution is not uniform, the uniform distribution temperature causes LG Z to distribute uniformly in the stirring region, which indicates that the effect of temperature on the grain size change in the stirring region is more obvious than that on the strain rate.The strain rate of the material point moving around the needle is obviously higher than that of the material point on the other trajectory, and can reach 22 s / 1.The boundary of mixing zone and thermal influence zone can be determined by tracking the flow behavior of different materials.The grain size of the mixing zone increases with the increase of the shaft shoulder of the mixing head, and the size of the mixing zone increases with the increase of the shaft shoulder of the mixing head.A smaller mixing head makes the area of the mixing area smaller.
【作者单位】：大连理工大学工程力学系;大连理工大学工业装备结构分析国家重点实验室;
【基金】：国家自然科学基金(11172057) 中央高校基本科研业务费专项资金教育部新世纪优秀人才支持计划(NCET-12-0075)资助项目
【分类号】：TG453.9

【共引文献】