摘要
增材制造(AM)技术依据数字化模型,将材料以逐层铺叠的方式制成产品。在逐层铺叠过程中,模型内部不同位置的温度变化较为复杂,为了监测增材制造过程中层叠结构打印模型内部不同位置的温度变化,本研究利用光频域反射技术(OFDR),将分布式光纤嵌入聚乳酸酯(PLA)材料模型内部,实现了对打印过程中任一时刻材料模型内部不同位置的温度变化的监测,同时考虑填充密度对模型温度变化的影响,设置填充密度分别为20%、40%、60%、80%、100%。结果表明,在打印过程中,模型在同一密度下不同位置点的内部温度变化量趋于一致,温度变化量范围为20~40℃;根据不同填充密度下模型的温度变化量曲线,将打印过程划分为5个典型阶段,包括光纤嵌入阶段、温度检测孔洞封装阶段、模型填充封装阶段、模型封顶阶段、模型温度回归阶段。分析模型填充封装阶段最高峰值点和模型封顶阶段完成点的温度变化量,发现100%填充密度下AM过程中模型核心最大温度较20%填充密度下高15℃,而且随着模型填充密度的增大,打印材料对温度消散的阻碍作用增强。
Additive manufacturing(AM)is a technology that makes materials into products through layer-by-layer stacking according to a digital model.Nevertheless,during the layer-by-layer stacking,the temperature change at different positions inside the model is complicated.To measure the temperature change at different positions inside the stacked structure printing model during the AM process,in this study,we embed the distributed fiber into the polylactic acid(PLA)material model by optical frequency domain reflectometry(OFDR).The temperature change at different positions inside the material model can be measured at any time during the printing process.Considering the effect of filling density on the temperature change in the model,the filling density is set as 20%,40%,60%,80%,and 100%,respectively.The results show that the internal temperature variation in the model with the same density at different locations tends to be consistent during the printing process,and the temperature change range is 20--40℃.According to the temperature variation curves in the model at different filling densities,the printing process is divided into five typical stages,including fiber embedding,thermometer hole encapsulation,model filling encapsulation,model capping,and model temperature regression.After analyzing the temperature changes at the peak point of model filling encapsulation and at the completion point of model capping,we find that the maximum temperature at the AM core with a 100% filling density is 15℃ higher than that with a 20%filling density,and with the increase in the filling density of the model,the printing material further hinders temperature dissipation.
作者
黄金生
洪成雨
杨强
孙晓辉
Huang Jinsheng;Hong Chengyu;Yang Qiang;Sun Xiaohui(College of Civil and Tramsportation Engineering,Shenzhen University.Shenzhen,Guangdong 518060,China;Shenzhen Key Laboratory of Green,Efficient and Intelligent Conustruction of Metro Underground Metro Station,Shenzhen,Guangolong 518060,China;Underground Polis Acodemy,Shenzhen Uninersity,Shenzhen,Guangdong 518060,China;Key Laborutory for Resilient Infrastructures of Coustal Cities(Shenzhen University),Ministry of Education,Shenzhen,Guangdong 518060,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2021年第16期17-24,共8页
Acta Optica Sinica
基金
国家自然科学基金面上项目(52078303)
国家自然科学基金高铁联合基金项目(U2034204)。
关键词
光纤光学
光频域反射技术
增材制造
温度监测
聚乳酸酯
fiber optics
optical frequency domain reflectometry
additive manufacturing
temperature monitoring
polylactic acid
