工程科学学报2017，Vol.39Issue(2)：202-207,6.DOI:10.13374/j.issn2095-9389.2017.02.006
添加Al2O3--ZrO2复合粉改性氧化锆质定径水口及其损毁机理
Damage mechanism of zirconia metering nozzles modified by Al2O3--ZrO2 composite powder
摘要
Abstract
The modified metering nozzles were fabricated by using sol-gel Al2O3-ZrO2 composite powder as additives in particle and ceramic type zirconia metering nozzles. The physical properties, mineral phase and microstructure of metering nozzles of particle and ceramic types before and after modification were studied and the damage mechanism of nozzles in continuous casting field test was analyzed. The results show that the ceramic type metering nozzle has lower apparent porosity, higher bulk density, higher compression strength and poorer thermal shock stability compared with the particle type metering nozzle. By adding Al2O3-ZrO2 composite powder, the apparent porosity of modified nozzles decreases, the bulk density and compression strength get higher, the thermal shock resistance of the particle type metering nozzle improves markedly, and the count of thermal shocks is about 1. 5 times of that before modification. After the analysis of residual samples in continuous casting field test for 35 h, the damage of the ceramic type nozzle is mainly caused by the fracture in the service process for the poor thermal shock stability, cracks generating in the fracture process cause a certain de-gree of flaking and hole enlargement. Due to low strength and high apparent porosity, flaking and hole enlargement of the unmodified type particle metering nozzle is more serious. The thermal shock, scouring and erosion resistance of the particle type nozzle after being modified by Al2O3-ZrO2 composite powder improve remarkably because of the formation of MgAl2O4 spinel enhanced phase, but little hole enlargement occurs after casting test.关键词
连铸/定径水口/陶瓷型/颗粒型/热震稳定性Key words
continuous casting/metering nozzles/ceramic type/particle type/thermal shock resistance分类
化学化工引用本文复制引用
赵亮,薛群虎..添加Al2O3--ZrO2复合粉改性氧化锆质定径水口及其损毁机理[J].工程科学学报,2017,39(2):202-207,6.基金项目
国家自然科学基金面上资助项目(51372193) （51372193）
陕西省自然科学基础研究计划资助项目(2014JM6224) （2014JM6224）
