基于高温发汗润滑多孔材料基体厚壁均质有序孔结构的特征,以薄壁蜂窝状结构为基础,引入表征其特征参数值λ,构建了新的多孔材料强度计算模型,推导出可在较宽参数范围内计算厚壁均质孔材料相对密度和孔隙率对其基体强度影响的表达式;并以金属陶瓷为材料基体骨架,计算了不同孔隙率材料的抗压强度,计算结果与传统多孔陶瓷材料经验公式理论值的一致性表明建立的计算模型具有较宽的工程适应性.在此基础上得出材料弹性模量随孔隙率的增大而减小,且当孔隙率小于0.6时,材料弹性模量减幅较大;材料泊松比随孔隙率的增大而增大,且当孔隙率大于0.4时,泊松比的增幅明显变大.

A new substrate strength calculation model for high-temperature and sweat-lubricating porous materials has been established by deducing its characteristic parameter of λ and traditional thin-walled honeycomb theory and it has been used to calculate the substrate strength of the order porous material with thick cell walls.The relationships among relative density,porosity and substrate strength were calculated and analyzed by using the model and taking the cermet as typical substrate material.The results show that the compressive strength decreased with the increase of the porosity and the relationship is consistent with traditional empirical value.The elastic modulus of the material decreased with the increase of the porosity,and the decreasing rate was larger within the porosity range of 0.6 than that beyond of the range;Poissons ratio of the material increased with the increase of the porosity,and when the porosity was larger than 0.4,the increase showed a higher rate.