基于DIC的3D打印不同构建取向成型试件的力学性能分析  

Mechanical properties analysis of 3D printed specimens with different orientations based on DIC

作　　者：张彬 钟宜辰 陈凡秀[1] 高新亚 王潇 张兆军 赵伟娜 周晓宾 ZHANG Bin;ZHONG Yi-chen;CHEN Fan-xiu;GAO Xin-ya;WANG Xiao;ZHANG Zhao-jun;ZHAO Wei-na;ZHOU Xiao-bin(School of Science, Qingdao University of Technology, Qingdao 266520, China;Qingdao Borrec 3D Manufacturing Co., Ltd., Qingdao 266000, China)

机构地区：[1]青岛理工大学理学院,山东青岛266520 [2]青岛博瑞科三维制造有限公司,山东青岛266000

出　　处：《液晶与显示》2021年第5期673-679,共7页Chinese Journal of Liquid Crystals and Displays

基　　金：国家自然科学基金(No.12072170,No.11472145)。

摘　　要：不同的构建取向对熔融沉积成型的标准试样的力学性能有着显著影响。本文采用聚乳酸线材,使用熔融沉积式3D打印方法制备站立式、侧立式、平躺式3种不同方向打印成型的试样,采用数字图像相关方法实时分析并记录试样拉伸与弯曲变形过程。使用该测量系统能够有效获取试样的真实变形与应变,结合试验机数据给出更为精确的应力-应变曲线,通过对应变云图中线状区域的观察能够准确地预测断裂发生的时间与位置,比较不同构建取向成型的工艺对打印制品的力学性能的影响。试验结果表明站立式打印的试件在拉伸试验和3点弯曲试验中没有明显颈缩现象,其变形、伸长率以及强度也是最低的,呈现出脆性材料所具有的特性。侧立式具有很好的抗拉性能,其颈缩现象出现后发生很小的变形就会断裂,所能承受的力呈现直线下降的趋势,直至断裂。平躺式的强度相近于侧立式,其发生颈缩现象直至断裂变形量相对侧立式要大,且应力随着变形的增大表现出较为平缓减小的特征,强度、延展性等呈现出最佳的机械性能。Different construction orientations have a significant influence on the mechanical properties of the standard samples of fused deposition modeling(FDM).In this paper,polylactic acid(PLA)wire rod was used to prepare three kinds of printing samples in three different directions:standing,side standing and lying down,The digital image correlation(DIC)method was used to analyze and record the tensile and bending deformation process of the sample in real time.The real deformation and strain of the sample can be obtained effectively by using the measurement system,and the more accurate stress-strain curve can be obtained combined with the test machine data.Through the observation of the linear region in strain nephogram,it can accurately predict the time and location of fracture,and compare the mechanical properties of different oriented forming processes on printed products performance impact.The test results show that there is no obvious necking phenomenon in the tensile test and three-point bending test,and its deformation,elongation and strength are also the lowest,showing the characteristics of brittle materials.The lateral vertical has good tensile properties.After the necking phenomenon occurs,it will fracture after a small deformation,and the force that it can bear presents a linear downward trend until it breaks.The strength of the lying down type are similar to those of the side standing type,and the necking phenomenon occurs until the fracture deformation is larger than that of the side standing type,and the stress decreases gently with the increase of deformation,showing the best mechanical properties in strength and ductility.

关 键 词：构建取向 熔融沉积成型 数字图像相关方法 力学性能 

分 类 号：O438.1[机械工程—光学工程]