激光透射焊接PMMA的工艺参数对焊接质量的影响

Influence of Process Parameters of Laser Transmission Welding PMMA on Welding Quality

热塑性塑料PMMA具有较高的透明性和化学稳定性,被广泛应用于汽车门窗、车灯等行业。采用碳黑作为吸收剂,探究PMMA激光透射焊接过程中工艺参数(碳黑含量、线能量密度和PMMA厚度)对焊接质量(拉断力和焊缝宽度)的影响,并对不同碳黑含量和线能量密度的焊缝断面形貌进行SEM观测。结果表明,随着碳黑含量和线能量密度的增大,焊接强度先增大后减小;随着PMMA厚度的增加,焊接强度不断增加,但增大的趋势逐步变缓。同时,3个因素与焊缝宽度都呈正相关。碳黑质量分数为0.15%、线能量密度为1.11 J·mm^(-1)时,可观测到“山脊状”的断面形貌,此时塑料充分熔融镶嵌,焊接质量好。

Thermoplastic PMMA has high transparency and chemical stability,and is widely used in automotive doors,windows,lights and other industries.In this paper,carbon black was used as an absorbent to explore the influence of process parameters(carbon black content,line energy density and PMMA thickness)on weld quality(tensile force and weld width)in PMMA laser transmission welding process,and SEM observations were made of weld section morphology with different carbon black content and line energy density.The results indicate that both carbon black content and line energy density initially enhance the welding strength,but excessive levels lead to a decline.In contrast,as PMMA thickness increases,the welding strength also increases,albeit with a gradually diminishing rate of improvement.Notably,all three factors exhibit a positive correlation with weld width.Notably,at an optimal carbon black content of 0.15wt.%and line energy density of 1.11J·mm^(-1),a“ridge-like”cross-sectional morphology is observed,indicating thorough plastic melting and inlaying,thus yielding excellent welding quality.