An efficient scanning algorithm for improving accuracy based on minimising part warping in selected laser sintering process

作     者：Yeganeh, A. Manshoori Movahhedy, M. R. Khodaygan, S. 

作者机构：Sharif Univ Technol Dept Mech Engn Azadi Ave Tehran Iran 

出 版 物：《VIRTUAL AND PHYSICAL PROTOTYPING》 (虚拟与实体成型技术)

年 卷 期：2019年第14卷第1期

页      面：59-78页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0802[工学-机械工程] 

主　　题：Additive manufacturing selective laser sintering scanning algorithm hatching pattern part warping finite element modeling 

摘      要：In the selective laser sintering (SLS) method, layers of powder are scanned by a laser beam and sintered. The thermal gradients created by laser heating and the subsequent cooling of the sintered sections results in thermal stresses and part warping in the final part. Thermal gradients are dependent on the scanning algorithm, in particular, the scan vector length. In this work, an efficient scanning algorithm for the SLS process is presented with the aim to minimise the part warping in the final part due to thermally induced residual stresses, while maintaining the production time at a minimum. The proposed algorithm is implemented in a finite element simulation and scanning parameters including the number of offsets and scanning length are optimised at constant laser parameters and chamber conditions. The FE model is verified by testing a few samples on SLS machine and comparing the parts made by the proposed algorithm with those made using conventional scan algorithm is the same as parallel-line scan algorithm. It is shown that part warping in the parts made by the proposed algorithm is reduced by up to 35% while the production time, part accuracy and surface properties are improved.