Development of Composite Binder System for Shell Mold in Precision Casting of Thin Stainless Steel
New composite binder systems have been developed to improve strength of shell mold and to decrease processing time, as functions of dipping time and binder composition, which is compared with the conventional binder system. The new binder systems were prepared by mixing tetraethyl orthosilicate (TEOS) and polydimethyl siloxane (PDMS) as precursor of SiO2 and sodium methoxide (NaOMe) as precursor of NaO2. The samples of shell mold were dipped into the prepared binder systems, and then heat-treated at 1000℃ for 1 hr. The fracture strength is sharply enhanced in the new binder system owing to the increase of penetration depth with the dipping time, whereas the conventional binder system is modestly increased even in the dipping time of 2 hr. The new binder system with 7.6 wt% PDMS shows the highest nominal strength, showing a nominal value of 16 GPa.When only PDMS as precursor of SiO2 was used in the new binder system, the increase of viscosity by PDMS causes a larger scattering in the strength value. The strength could be controlled with the dipping time and molecular weight, showing the lower nominal strength values at the dipping time of 0.5 hr and in the low molecular weight of TEOS/NaOMe. The relationship between strength and binder composition is discussed, based on the microstructures before and after heat-treatment.
Composite binder Composition Shell mold Fracture strength Penetration depth
Woo-Ram Lee Eun-Hee Kim Jae-Young Kwon Jae-Hyun Kim Yeon-Gil Jung
School of Nano and Advanced Materials Engineering, Changwon National University, #9 Sarim-dong, Changwon, Kyungnam 641-773, Korea
国际会议
10th International Symposium on Eco-Materials Processing and Design(第10届国际生态材料加工与设计研讨会)
西安
英文
315-318
2009-01-13（万方平台首次上网日期，不代表论文的发表时间）