核壳结构SiC@Ti(C,N)复合材料的制备及性能研究  

Preparation and Properties of Core-shell SiC@Ti(C,N)Composites

作　　者：黄绍锋 甘志伟 胡宁飞 陆静 李东旭[1] HUANG Shao-feng;GAN Zhi-wei;HU Ning-fei;LU Jing;LI Dong-xu(College of Materials Science and Engineering,Huaqiao University,Fujian Xiamen 361021,China;Institute of Manufacturing Engineering,Huaqiao University,Fujian Xiamen 361021,China)

机构地区：[1]华侨大学材料科学与工程学院,福建厦门361021 [2]华侨大学制造工程研究院,福建厦门361021

出　　处：《表面技术》2023年第4期410-416,426,共8页Surface Technology

基　　金：国家自然科学基金(51975222);亚稳材料制备技术与科学国家重点实验开放课题(202207)。

摘　　要：目的 碳化物陶瓷材料因优异的力学性能在精加工和切削行业具有广阔的应用前景,制备特定结构的碳化物复合材料能够改善材料的综合性能。方法 通过化学法在SiC表面包覆纳米Ti(C,N),无压烧结制备了具有核壳结构的SiC@Ti(C,N)复合材料。采用XRD、SEM、TEM和EDS等方法,研究退火温度和原料配比对复合材料的成分组成和微观结构的影响。通过同步热分析(TG-DSC)比较单相和复合材料抗氧化性能差异。使用显微维氏硬度计和万能材料试验机测试材料力学性能的变化趋势及原因。构建核壳颗粒致密化模型,分析复合材料的致密化机制和增韧机理。结果 随着烧结温度的升高,其显微硬度先升高后降低。随着SiC比例的增大,其显微硬度、压缩强度和断裂韧性均先增大后减小。在1250℃下,制备的原料质量比为11:1的SiC@Ti(C,N)复合材料具有最大显微硬度、压缩强度和断裂韧性,分别为3 273HV、434 MPa、4.38MPa·m^(1/2)。结论 通过比较复合材料和单一碳化物材料的力学性能发现,具有核壳结构的SiC@Ti(C,N)复合材料综合性能得到提升。纳米Ti(C,N)填充复合材料孔隙并促进致密化烧结,从而提升了复合材料的强度;通过Ti(C,N)骨架的偏转裂纹实现增韧。Carbide ceramic materials present widely applications in fine polishing and cutting industries due to their excellent mechanical properties.The preparation of carbide composite materials with specific structure will improve the comprehensive properties of materials.SiC@Ti(C,N)composites with core-shell structure were prepared by chemically coating nano-Ti(C,N)on the surface of 10 micron SiC and press-free sintering at low temperature in a tubular furnace.XRD,SEM,TEM and EDS were used to study the effects of annealing temperature and raw material ratio on the composition and microstructure of composite materials.The difference of oxidation resistance between single-phase and composite materials was compared by thermal analysis.The variation trend and reason of mechanical properties of composite materials were tested by micro-Vickers hardness tester and universal material testing machine.A model of core-shell partical densification was built to discussed the densification and toughened mechanisms of SiC@Ti(C,N)composites.The composition and microstructure of the composites are the core-shell structure of thin sheet Ti(C,N)coated SiC particles,which improves the oxidation resistance of the composites.As the sintering temperature increases,its microhardness increases firstly and then decrease.With the mass ratio of SiC/Ti(C,N)as a variable,the experimental results show that as the proportion of SiC increases,the microhardness,compressive strength and fracture toughness increase firstly and then decrease,the microhardness of SiC@Ti(C,N)composites prepared under the optimal experimental conditions surpasses that of SiC.The results show that the SiC@Ti(C,N)composites with raw material ratio of 11∶1 fabricated at 1250℃have maxium microhardness,compressive strength and fracture toughness,which are 3273HV,434 MPa and 4.38 MPa·m^(1/2) respectively.The properties of SiC@Ti(C,N)composites with core-shell structure are improved by comparing the mechanical properties of composites and single carbide materials.The densifica

关 键 词：碳化硅陶瓷 碳氮化钛 断裂韧性 核壳结构 显微硬度 增韧机理 

分 类 号：TB333[一般工业技术—材料科学与工程]