摘要
采用应力设计及热膨胀失配的原理,从微观结构入手,通过调整颗粒配比(粗颗粒的临界粒径、熟料细粉含量及中间颗粒含量)制备MgO-CaO陶瓷试样;探讨了颗粒配比、显气孔率等因素对试样体积密度、抗热冲击性能及热冲击对试样抗折强度的影响。实验结果表明:适当的颗粒级配使得MgO-CaO陶瓷中,颗粒与基质之间存在一定的残余应力,基质与气孔中气体之间存在热膨胀系数差异;当热震损伤产生的裂纹遇到颗粒及气孔时会发生偏转、分岔和钉扎,从而有效地改善MgO-CaO陶瓷的抗热震稳定性能。
Stress design and the thermal expansion mismatch theory have been used,beginning with the micro-structure,to prepare the MgO-CaO ceramic sample by adjusting the granule mixture ratio（critical size of the coarse granule,the content of the clinker/fine aggregate and the intermediate granule content）.After that,a set of experiments are carried out to probe into how different mixture ratios and apparent porosities affect the bulk density and thermal shock resistance and how the cycles of thermal shock affect the flexural strength of the specimens.According to the results of the experiment,appropriate mixture ratio leaves certain residual stress between the MgO-CaO ceramic particles and the matrix,and differences in thermal expansion coefficient exist between the matrix and the gas in the pores;when cracks produced by thermal shock damage encounter particles and pores,deflection,bifurcation and pinning occur,which can effectively improve the thermal shock resistance of MgO-CaO ceramic.
出处
《陶瓷学报》
CAS
北大核心
2010年第2期229-233,共5页
Journal of Ceramics
关键词
热冲击
显气孔率
抗折强度
thermal shock
apparent porosity
flexural strength
