水玻璃加入量对VRH-CO_2法硬化水玻璃砂的影响  

Effects of Addition of Sodium Silicate on Tensile Strength of Hardening Sodium Silicate Sands by VRH-CO_2

作　　者：车广东[1] 刘向东[1] 

机构地区：[1]内蒙古工业大学材料科学与工程学院,内蒙古呼和浩特010051

出　　处：《铸造技术》2014年第2期334-336,共3页Foundry Technology

摘　　要：采用VRH-CO2法硬化水玻璃砂,在一定真空度和CO2吹气压力条件下,研究了水玻璃加入量对试样抗拉强度的影响规律,并用扫描电镜观察了试样断口形貌及砂粒表面水玻璃膜的特征。研究结果表明,在0.056 MPa的真空度及0.04 MPa的CO2气体压力下,水玻璃砂抗拉强度随水玻璃加入量的增加而增大,随着保压时间的延长,抗拉强度略有降低。试样失效形式为脆性断裂。The effects of addition of sodium silicate on the tensile strength of hardening sodium silicate sand were investigated by VRH-CO2 technology in a constant vacuum degree and at a constant pressure of CO2 gas flow. The fracture morphology of the specimens and the characteristics of sodium silicate film on the surface of sands were observed by SEM. The results show that the tensile strength of sodium-silicate sands increases with the increase of the amount of sodium silicate, and the tensile strength is slightly reduced as the extension of the holding time in 0.056 MPa vacuum degree and 0.04 MPa CO2 gas pressure. Besides, it is found that failure mode of sodium silicate sands is brittle fracture.

关 键 词：水玻璃砂 VRH-CO 2硬化 抗拉强度 断口形貌 

分 类 号：TG221[金属学及工艺—铸造]