原位生长莫来石棒晶增强钡长石基复合材料的制备及性能

以煤矸石、碳酸钡和氧化铝为原料,采用同相反应热压烧结法制备了原位生长莫来石棒晶增强 BAS 复合材料,借助于 XRD 和 SEM 研究烧成温度和配比对复合材料的相组成、结构和性能的影响。结果表明:热压烧结制备的致密均匀的复合材料,各相结合紧密,均匀分布,莫来石呈针状或棒状,形成空间网络结构;温度的升高,有利于材料的致密化和力学性能的改善,在1450℃×1h×20 MPa 时,按 m(BaO):m(Al_2O_3):m(SiO_2)=30:15:55的配比制备的材料可以获得优异的力学性能。弯曲强度为215 MPa,断裂韧性为3.8 MPa·m~(1/2),比纯钡长石基体材料分别提高169%和111%。

Fabrication and properties of in-situ mullite rodlike crystal reinforced BAS composite

In-situ mullite rodlike crystal reinforced BAS composite was fabricated by solid phase reaction and hot-pressing sintering method,using coal-gangue,alumina and barium carbonate as raw materials.XRD and SEM were employed to study effects of firing temperature and composition on phase composition,structure and properties of the composite.The results showed that the uniform and compact composite could be fabricated by hot pressing,and the distribution of phases was uniform,rod-like or needle-like mullite distributed netlike structure in space.The increase of firing temperature was beneficial to the densification of the material and improvement of mechanical properties.According to the composition of m(BaO):m (Al_2O_3):m(SiO_2)=30:15:55,under the condition of 1 450 ℃×1h×20 MPa,the composite possessed super mechanical properties.And the flexural strength and fracture toughness was 215 MPa and 3.8 MPa·m~(1/2),which were 169% and 111% higher than that of BAS matrix respectively.