TiB2-Cu基金属陶瓷高温烧蚀行为研究  

High-temperature ablation behavior of TiB_2-Cu matrix cermets

作　　者：徐丽[1] 韩杰才[1] 张幸红[1] 徐强[2] 

机构地区：[1]哈尔滨工业大学复合材料与结构研究所,黑龙江哈尔滨150001 [2]北京理工大学材料科学与工程学院,北京100081

出　　处：《材料科学与工艺》2009年第2期270-273,277,共5页Materials Science and Technology

基　　金：国家自然科学基金重点资助项目(90205034);自然科学基金重点项目(90505015)

摘　　要：为研究TiB2-Cu基金属陶瓷材料的高温烧蚀行为,采用燃烧合成与同时致密化技术(SHS/PH IP)制备了TiB2-40Cu及TiB2-40Cu-8N i金属陶瓷复合材料.利用电弧风洞试验考察了材料的抗热震和抗烧蚀性能,利用扫描电镜、电子探针及X射线衍射等方法对材料烧蚀前后的微观组织形貌及成分进行了检测.结果表明,试验模型表面均有烧蚀冲刷痕迹,TiB2-40Cu模型由于抗热震性较差,其表面有裂纹出现,TiB2-40Cu-8N i的质量烧蚀率较TiB2-40Cu的质量烧蚀率低.微观组织分析表明,TiB2-40Cu模型烧蚀面中心区域剖面附近存在沿厚度方向100μm左右的烧蚀区.TiB2-40Cu复合材料的烧蚀机理为金属相的熔化、化学烧蚀和机械剥蚀.Both titanium diboride-copper-nickel and titanium diboride-eopper cermets were fabricated by combustion synthesis, under conditions of pseudo hot isostatic pressing. The samples were heated by a wind tunnel instrument to investigate the thermal shock resistance and ablation behavior. The microstructures and constituents Of the cermets pre-and post-ablation were examined by SEM, EPMA and XRD. The result shows that there are some scour marks on the surface of samples after ablation, and cracks are found on the surface of TiB2 -40Cu sample due to its bad thermal shock resistance. The mass loss ratio of TiB2 -40Cu- 8Ni cermet after ablation is lower than that of TiB2 -40Cu. The result of SEM shows that there is an ablation area about 100 μm near the ablation surface of TiB2 -40Cu. The ablation mechanism of TiB2 -40Cu cermet is the melting of metal binder, hot chemical ablation and mechanical erosioh.

关 键 词：TiB2-Cu基金属陶瓷 抗热震 烧蚀行为 烧蚀机理 

分 类 号：TB333[一般工业技术—材料科学与工程]