摘要
选择激光熔覆技术在GH586镍基高温合金表面上制得了不同Hf含量的CoCrAlYSiHf涂层,并对涂层微观组织形态与涂层耐高温性能进行实验测试分析。研究结果表明:采用激光熔覆方法得到的涂层表面上形成了许多网状组织,在未添加Hf涂层的晶界部位产生了许多孔隙结构;在Hf含量0.1和0.3涂层内形成了更多的孔隙,同时沿晶区域产生了众多显微裂纹。在涂层的表面形成了许多具有致密结构的Cr2O3膜。涂层经过100h高温氧化处理依然由致密Cr2O3膜组成。未添加Hf涂层表面生成了约6μm厚的致密氧化膜,并且沿晶界处发生了一定成对内氧化。当Hf含量0.1和0.3涂层经过100 h高温氧化之后,其表面生成了厚度约12μm的氧化膜并含有较多孔隙。
The Hf-doped CoCrAlYSi coatings were synthesized by laser cladding on substrate of Ni-based GH586 super-alloy. The influence of the Hf-content on the microstructures and oxidation resistance was investigated with X-ray diffraction, energy dispersive spectroscopy, scanning electron microscopy and oxidation-test at 1100℃ for 100 h. The results show that the Hf-content had a major impact. For instance, the crack-free reticular structures and many pores at the grain-boundary co-exist on the surfaces of laser cladded CoCrAlYSi coating. As the Hf-content increased from 0.1 to 0.3 in the CoCrAlYSiHfx coatings, dominated by γ-Co phase, the pore and micro-crack densities increased, possibly because the laser induced degassing and oxidation at grain-boundary. In oxidation test, 6 and 12 μm thick oxide-layers formed on CoCrAlYSi and CoCrAlYSiHfx surfaces, respectively, and the 12 μm thick, compact porous Cr2O3-layer was found to display strong oxidation-resistance even at 1100℃.
作者
张静
王丽娜
彭玉涛
赵飞
Zhang Jing;Wang Lina;Peng Yutao;Zhao Fei(Department ofMechanical and Electrical Engineering,Jizhong Vocational College,Dingzhou 073000,China;Commercial Vehicle Development Institute of Faw Jiefang Automobile co.,LTD.,Dingzhou 073000,China;MCC Tiangong Group Co.,Ltd,Tianjin 300308,China;College of Mechanical Engineering,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2020年第3期203-206,共4页
Chinese Journal of Vacuum Science and Technology
基金
山西省自然科学基金项目(201510203306)。
