摘要
目的提高PA66塑料的焊缝剪切强度,达到实际生产要求。方法采用高速扫描振镜对PA66塑料进行扫描激光焊接,分析重复焊接次数对塑料焊缝外观及剪切强度的影响,并且对焊缝截面进行测试,分析工艺参数对焊缝截面的影响规律。通过对工艺参数(激光平均功率、重复焊接次数、焊接速度、离焦量)进行四因素四水平正交实验,得到焊缝剪切强度最大的工艺参数。结果焊缝剪切强度最大为174 MPa,达到母材剪切强度的91%,对应的最佳工艺参数为,激光平均功率为70 W,焊接速度为900 mm/s,离焦量为6 mm,重复扫描次数为30。影响焊缝剪切强度的主要参数为重复焊接次数,其次为焊接速度,再次为离焦量,最次为激光平均功率。结论采用高速重复扫描焊接,塑料每次吸收的激光能量较低,通过热量逐渐积累而达到焊接的效果,可以有效解决塑料中杂质产生的焊缝烧伤,而且焊缝轨迹更加均匀一致,提高了焊缝剪切强度,满足实际生产要求。
The work aims to improve the shear strength of PA66 plastics welds,so as to meet the actual production require-ments.The high speed scanning galvanometer was used to carry out scanning laser welding for PA66 plastics.The effects of re-peated welding times on the appearance and shear strength of plastic welds were analyzed,and the cross section of welds was tested.Then,the effect of process parameters on cross section was analyzed.Four-factor and four-level orthogonal experiments were carried out to process parameters(laser power,repeated welding times,welding speed and defocus)to obtain the parameter for the maximum shear strength of the welds.The maximum shear strength of welds was 174 MPa,reaching 91%of the parent material strength.The corresponding optimal process parameters were average laser power of 70 W,welding speed of 900 mm/s,defocusing amount of 6 mm,and repeated scanning times of 30 times.The factors affecting the shear strength of the welds were repeated welding times,welding speed,and average laser power in the order of primary to secondary.With high speed repeated scanning welding,the laser energy absorbed by the plastic is low every time,and the welding effect is achieved through the gradual accumulation of heat,which can effectively solve the weld burn caused by impurities in the plastic,and the weld trajec-tory is more uniform and consistent,which improves the shear strength of the weld and meets the actual production require-ments.
作者
题园园
TI Yuan-yuan(Guangzhou Institute of Technology,Guangzhou 510900,China)
出处
《精密成形工程》
北大核心
2022年第3期102-106,共5页
Journal of Netshape Forming Engineering
基金
2021年校级质量工程立项项目-教育教学改革项目(YJG202106)
2021年校级质量工程立项项目-大学生创新创业训练项目(YDC202106)。
关键词
重复扫描
PA66塑料
激光焊接
工艺研究
repeated scanning welding
PA66 plastics
laser welding
process research
