【摘要】 洁净钢生产及冶金绿色化发展推动含碳耐火材料向低碳化转型，石墨含量降低导致的抗热震性能恶化已成为其亟待解决的关键问题。本文论述了耐火材料抗热震理论和抗热震性能测试方法的研究进展，同时依据强韧相组成及特性分类，对近年来低碳铝碳耐火材料抗热震性能提升的相关研究进行了综述与评估。基于偏离线弹性的断裂力学理论以及应变能-断裂表面能关系，并结合楔形劈裂测试方法，可以定性描述或定量评估耐火材料的抗热震性能。缓解应力集中以降低弹性应变能储存或提高断裂能以增加弹性应变能消耗路径均能有效改善低碳耐火材料的抗热震性能。通过外部添加或原位生成低维纳米碳、低维陶瓷相、复合相等增强增韧相，发挥“桥连”“拔出”“裂纹偏转”“应力释放”等作用能显著改善低碳铝碳耐火材料的抗热震性能。引入h-BN或Max相等抗氧化、抗热震性能优异的类石墨相替代石墨也可制备具有高抗热震性的低碳铝碳耐火材料。更多还原

【Abstract】 The demand for clean steel production and greener metallurgy is driving carbon-containing refractories toward low-carbonization. However,the reduction in graphite content deteriorates the thermal shock resistance,which has become the most urgent challenge for low-carbon refractories. This paper first reviews the theoretical models and test methods used to evaluate the thermal shock behaviour of refractories. Then,according to the composition and characteristics of the toughening phases,recent studies aimed at improving the thermal shock resistance of low-carbon Al₂O₃-C refractories are summarized and critically assessed. Based on the fracture mechanics deviated from linear elasticity and the relationship between strain energy and fracture surface energy,combined with the wedge splitting test,the thermal shock resistance of refractory materials can be qualitatively described or quantitatively evaluated. Mitigating stress concentration to reduce the stored elastic strain energy or raising the fracture energy to increase the elastic strain energy consumption path can both effectively improve the thermal shock resistance of low-carbon refractories. External addition or in-situ generation of low-dimensional nanocarbons,ceramics,or compounds as toughening phases can activate “bridging”,“pull-out”,“crack deflection”,and “stress relief” mechanisms,thereby markedly enhance the thermal shock resistance of low-carbon Al₂O₃-C refractories. Additionally,replacing graphite with graphite-like substitutes that exhibit superior oxidation and thermal shock resistance—such as h-BN or MAX phases—also offers a promising approach to low-carbon Al₂O₃-C refractories with high thermal shock tolerance.更多还原