摘要
基于搅拌摩擦焊接的完全热力耦合模型,跟踪材料物质点运动轨迹,划分出不同搅拌头转速下搅拌区域边界。沿材料物质点迹线提取出真实应变与温度历程,可进一步计算Zener-Hollomon参数并利用经验公式预测搅拌区晶粒尺寸。经计算发现较大转速工况下,搅拌区尺寸较大。搅拌区晶粒尺寸随焊接温度的增加而增加,随应变率的增加而减小。随着搅拌头转速的增加,焊接区材料温度与等效应变率均有明显增长,但是温度影响更为明显,平均晶粒尺寸随搅拌头转速的增加而增加。
The flow tracers of material particles are considered to determine the boundary of the stirring zone in friction stir welding based on a fully coupled thermo mechanical model.The real strain tensors and temperature histories are given from the tracer movements to calculate the Zener-Hollomon parameters.The grain sizes can be then predicted by the empirical formation.The width of SZ on the top surface can increase with the increase of the rotation speed.The average grain size in SZ can be increased with the increase of the welding temperature and can be decreased with the increase of the strain rates.Both the temperature and the strain rates can be obviously increased with the increase of the rotating speed.But the effect of the welding temperature is more obvious,the average grain size is increased with the increase of the rotating speed.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2015年第7期1-7,共7页
Journal of Materials Engineering
基金
国家自然科学基金项目(11172057)
国家重点基础研究发展(973)计划(2011CB013401)
中央高校基本科研业务费专项资金和新世纪优秀人才支持计划(NCET-12-0075)
