以Si_3N_4、B4C、C、Si等粉末为原料,采用机械合金化方法制备2Si-B-3C-N粉末,在氮气保护下1900 ℃, 40 Mpa热压烧结30 min获得2Si-B-3C-N陶瓷,研究了块体陶瓷微观组织结构与力学性能.高能球磨粉末在热压烧结后致密度达到了97.9%.热压烧结的2Si-B-3C-N陶瓷中主要含有等轴状的b-SiC和层片状的h-BCN相.BCN晶粒尺寸约为200 nm,SiC晶粒尺寸约为400～500 nm.BCN晶粒主要分布在SiC晶粒周围.2Si-B-3C-N陶瓷的室温抗弯强度、弹性模量、断裂韧性、硬度分别为446.6 Mpa、144.6 Gpa、5.10 Mpa×m~(1/2)和5.53 Gpa.在高温空气状态下,2Si-B-3C-N陶瓷的抗弯强度随温度的升高而降低,1000和1400 ℃下的抗弯强度分别为358.7和202.1 Mpa.
2Si-B-3C-N powders were prepared by mechanical alloying with Si_3N_4, B_4C, C and Si as starting materials and they were hot pressed at 1900 ℃ under 40 Mpa for 30 min in N_2 atmosphere to obtain 2Si-B-3C-N ceramic. Microstructure and mechanical properties of the bulk ceramic were studied. After hot pressing the density of the powder was up to 97.9%. The Hped ceramic was mainly composed of equiaxed β-SiC and lamellar h-BCN phase. The size of BCN grains was about 200 nm and that of SiC about 400～500 nm. BCN grains distributed around SiC grains. The flexural strength, elastic modulus, fracture tough and Vickers hardness were 446.6 Mpa, 144.6 Gpa, 5.10 Mpa~(1/2) and 5.53 Gpa, respectively. In air atmosphere at high temperature, the flexural strength decreased as the temperature increasing, which was 358.7 Mpa and 202.1 Mpa at 1000 ℃ and 1400 ℃, respectively.
参考文献
| [1] | Magnani G;Minoccari G L;Pilotti L .[J].Ceramics International,2000,26(05):495. |
| [2] | Steen M;Ranzani L .[J].Ceramics International,2000,26(08):849. |
| [3] | Sinclair W;Simmons H .[J].Journal of Materials Science Letters,1987,6:627. |
| [4] | Yang ZH;Ha DC;Zhou Y;Meng QC;Shi PY;Song CB .Thermal shock resistance of in situ formed SiC-BN composites[J].Materials Chemistry and Physics,2008(2/3):476-479. |
| [5] | Zhang G J;Ohji T .[J].Journal of the American Ceramic Society,2001,84(07):1475. |
| [6] | 杨冶华;贾德昌;周玉 et al.[J].稀有金属材料与工程,2005,34(z1):544. |
| [7] | Zhang D L .[J].Progress in Materials Science,2004,49:537. |
| [8] | Suryanarayana C. .Mechanical alloying and milling [Review][J].Progress in materials science,2001(1/2):1-184. |
| [9] | Yang Zhihua;Jia Dechang;Zhou Yu et al.[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,2008,488(1-2):241. |
| [10] | Dressler W;Riedel R .[J].International Journal of the Refractory Metals and Hard Materials,1997,15:13. |
| [11] | Li Z;Bradt R C .[J].Journal of Materials Science,1986,21:4366. |
| [12] | Li Z;Bradt R C .[J].Journal of Materials Science,1986,69(12):862. |
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