Study on the Deformation Behavior of Variable Wall Thickness Sand Mold by a 3D Printing Posttreatment Process

Author of the article:GUO Zhi1 , WANG Shaozong1 , RAN Yuelong1 , CHEN Wengang1 , TENG Shaodong1 , WANG Chao2

Author's Workplace：1. Beijing National Innovation Institute of Lightweight Ltd., Beijing 100044, China; 2. Key Laboratory of Electromechanical Integration Application Technology of Yunnan, Kunming 650031, China

Key Words：3D printing; variable wall thickness sand mold; posttreatment process; roller compaction and layered heating

Abstract：In recent years, sand-type 3D printing technology based on the principle of droplet ejection has achieved rapid development, attracting increasing attention from engineers and technicians. However, the current sand mold 3D printing technology postprocessing process causes the problem of deformation of the variable wall thickness sand mold. In this paper, the combination of simulation analysis and experimental research was put forward to qualitatively analyze the cause of sand mold deformation during posttreatment and then quantitatively study the influence of wall thickness variation and posttreatment temperature on sand mold deformation behavior. It is found that the uneven temperature field distribution during the posttreatment of the 3D printing sand mold can cause the thermal stress deformation of the sand mold, which will intensify with the increasing thickness variation of the printing sand mold and posttreatment temperature. Aiming at this problem, an auxiliary forming device and method based on roller compaction and layered heating is proposed, which effectively eliminates the problem of sand posttreatment deformation, providing theoretical guidance for the engineering application of sand 3D printing.