Preparation of coated sand for selective laser sintering and optimization of baking process of sand moulds  

作　　者：Peng-wei Wang Rui-long Yu Rui Tan Yan Wang Ying-wei Zhou Yue-ting Ma Yan-hai Li Jia-jun Liu Shao-kui Yin 

机构地区：[1]Shenyang Research Institute of Foundry Co.,Ltd.CAM,Shenyang 110022,China [2]National Key Laboratory of Advanced Casting Technologies,Shenyang 110022,China

出　　处：《China Foundry》2023年第6期519-525,共7页中国铸造（英文版）

基　　金：This work was financially supported by the Joint Funds of the National Natural Science Foundation of China(Grant No.U1808216);the Shanxi Provincial Key Research and Development Project(2022ZDYF072).

摘　　要：A cold method was used to prepare coated sand for application in the selective laser sintering(SLS)process.Tensile strength,loss on ignition,gas evolution,and accuracy of the SLS samples were tested and analyzed,and the baking process was thoroughly investigated.Compared with coated sand prepared by the hot method,the cold method yields a more uniform and complete resin film on the sand's surface,resulting in enhanced tensile strength and accuracy.Additionally,the cold method requires a lower binder content to meet the same strength requirements,thereby minimizing gas evolution,reducing porosity defects,and ultimately improving casting quality.The coated sand samples prepared through the cold method exhibit superior accuracy,with a size error of within±0.4 mm.In contrast,the coated sand samples prepared by the hot method display a lower accuracy,with an average negative error of 2.1993 mm.The highest tensile strength could be attained by controlling the baking temperature within a suitable range(180-190°C),which can effectively reduce the generation of gas,thus contributing to improved overall performance.

关 键 词：selective laser sintering(SLS) coated sand cold method hot method BAKING 

分 类 号：TG221.1[金属学及工艺—铸造]