【作者】 李均钦； 孙伟安； 谷坤明； 汤皎宁；

【Author】 Li Junqin, Gu Kunming, Tang Jiaoning and Xie Shenghui Department of Materials Science and Engineering, Shenzhen University, Shenzhen 518060. P. R. China. Shenzhen Key Laboratory of Special Functional Materials, Shenzhen 518060. P. R. China.

【机构】 深圳大学材料科学与工程系、深圳市特种功能材料重点实验室；

【摘要】 采用NiO,Al和Cr粉末反应热压制备了Al2O3/NiCrAl复合材料,具有良好高温性能的NiCrAl 合金是由NiO还原出来的Ni与添加的Cr和Al反应形成的。添加适量的Ni、Cr、Al金属粉末或Al2O3 陶瓷粉末成功地制备了不同Al2O3陶瓷含量的Al2O3／NiCrAl复合材料,并以Al2O3陶瓷体积百分数分别为25、52．2和75的Al2O3/NiCrAl复合材料为过渡层制备了Y稳定氧化锆(YSZ)到NiCrAl合金的功能梯度材料。X射线物相分析,金相观察和热循环冲击试验结果表明用该方法制备的复合材料由 Al2O3陶瓷相和(Ni,Cr,Al)固溶体组成,而Al2O3颗粒是由NiO与Al原位反应形成,尺寸细小,弥散分布。该功能梯度材料经从室温到1000℃空气中10次热循环后未发现有裂纹,表明该方法制备的材料陶瓷相与合金相有良好的相容性、较高的结合强度、良好的耐高温抗氧化及热循环冲击性能。更多还原

【Abstract】 The Al2O3/NiCrAl composites were fabricated by mixing NiO, Al and Cr powders using reactive hot pressing method. The NiCrAl alloy with good high temperature properties was formed by the reaction of extra Al, Cr and the Ni reduced from NiO. The Al2O3/NiCrAl composites with varies Al2O3 fraction were successfully fabricated by the proper addition of Ni、 Cr、 Al or Al2O3 powders. A 5-layer functional gradient materials of YSZ-NiCrAl was fabricated using the composites with compositions 25, 52.2, 75 as interlayers. The results from XRD analysis, optical microscope observation, hardness measurement and thermal cycling test shows that the composites fabricated by this method consists of Al2O3 phase and Ni(Cr, Al) solid solution. The Al2O3 grains formed by the in-situ reaction between NiO and Ni were fine and dispersive. No cracking was found in the functional gradient materials after 10 thermal cycles up to 1000 ℃. Experimental results show that the composites or functional gradient material fabricated in this work have strong strength, good resistance to wear and thermal shock. They can be used under 1000 ℃.更多还原