摘要
铝铬固溶体被广泛应用于耐火材料,其烧结致密化较难,添加一定量的烧结助剂有利于提高铝铬固溶体的致密程度,但对于致密化过程中的晶粒生长规律尚不清楚。在本工作中以纳米η-Al_(2)O_(3)和工业铬绿为原料,加入烧结助剂TiO_(2),并以PVA作为结合剂,经过冷等静压成型后在常压下1400~1700℃进行固相烧结制备摩尔比1∶1的烧结铝铬固溶体。利用Archimedes法、XRD、SEM、Nano measurer等手段分析了烧后试样的致密度、物相组成、显微结构和平均晶粒尺寸,在此基础上进一步计算研究了TiO_(2)的添加对铝铬固溶体的烧结动力学的影响。结果表明:在烧结过程中,Al_(2)O_(3)-Cr_(2)O_(3)和Al_(2)O_(3)-Cr_(2)O_(3)-2%TiO_(2)烧结体系的晶粒生长指数和晶粒生长活化能均随温度升高而减小;Al_(2)O_(3)-Cr_(2)O_(3)体系晶粒生长主要受原子随机越过晶界和体积扩散两种机制控制,Al_(2)O_(3)-Cr_(2)O_(3)-2%TiO_(2)体系晶粒生长主要受体积扩散控制;对比两种体系发现TiO_(2)的添加能使样品的晶粒生长指数和晶粒生长活化能下降,促进晶粒生长发育。
Aluminum chromium solid solution is widely used in refractory materials,but it’s hard to achieve sintering and densification.Adding a certain amount of sintering additives can effectively improve its density,but the rule of grain growth in the densification process is still unclear.In this experiment,nanoη-Al_(2)O_(3) and industrial chromium green were used as raw materials,with TiO_(2) as sintering aid and PVA as the binder,after being formed by cold isostatic pressing,the sintered aluminum chromium solid solution with the mole ratio of 1∶1 was prepared by solid phase sintering at 1400℃to 1700℃under normal pressure.The density,phase composition,microstructure,and average grain size of the sintered samples were analyzed by Archimedes method,XRD,SEM,and Nano measurer.On this basis,the effect of TiO_(2) on sintering kinetics of aluminum chromium solid solution was further calculated and studied.The results show that during the sintering process,the grain growth index and activation energy of Al_(2)O_(3)-Cr_(2)O_(3) and Al_(2)O_(3)-Cr_(2)O_(3)-2%TiO_(2) sintered systems decrease with the increase of temperature.The grain growth of Al_(2)O_(3)-Cr_(2)O_(3) system is mainly controlled by atoms crossing grain boundaries randomly and volume diffusion,the grain growth of the Al_(2)O_(3)-Cr_(2)O_(3)-2%TiO_(2) system is mainly controlled by volume diffusion.Compared with the two systems,it is found that the addition of TiO_(2) can decrease the grain growth index and activation energy of grain growth,and promote the grain growth and its development.
作者
李人骏
张玲
张晓序
王志刚
胡於江
LI Renjun;ZHANG Ling;ZHANG Xiaoxu;WANG Zhigang;HU Yujiang(School of Materials and Metallurgy,Liaoning Science and Technology University,Anshan 114051,China)
出处
《硅酸盐通报》
CAS
北大核心
2021年第6期2104-2109,共6页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金区域联合基金(U20A20239)。
作者简介
李人骏(1995—),男,硕士研究生。主要从事耐火材料方面的研究。E-mail:1245102850@qq.com;通信作者:张玲,博士,教授。E-mail:452433876@qq.com。
