Al2O3-YAG eutectic ceramic has become an ideal alternative to high-temperature alloys because of its excellent high temperature strength, high oxidation resistance and high temperature structural stability. The technology of laser engineered net shaping was used to prepare the Al2O3-YAG eutectic ceramic thin-wall samples. These samples were prepared on a common substrate and a water-cooled constant temperature substrate respectively. Their microstructure and microhardness were compared. The results show that the microstructure of thin-wall sample prepared on the common substrate is three-dimensional network structure with an average eutectic spacing of 0.96 μm. And the microstructure of top part of the sample prepared on the water-cooled constant temperature substrate is colony structure, while the microstructure of bottom part is dendrite structure which grows in the reverse direction of the heat flow. The average eutectic spacing of samples prepared on the water-cooled substrate has reduced to 0.21 μm. Compared with the microhardness of two kinds of thin-wall samples prepared on the different substrates, it is found that the microhardness of the thin–wall samples prepared on the water-cooled constant temperature substrate is increased by about 10%.
Effect of constant temperature substrate on microstructure and hardness of Al2O3-based eutectic ceramics
First published at:Dec 15, 2017
Opto-Electronic Engineering Vol. 44, Issue 12, pp. 1194 - 1199 (2017) DOI:10.3969/j.issn.1003-501X.2017.12.007
1 Williams James C, Starke Edgar A. Progress in structural materials for aerospace systems[J]. Acta Materialia, 2003, 51(19): 5775-5799.
2 Feng Q, Picard Y N, Liu H, et al. Femtosecond laser micromachining of a single-crystal superalloy[J]. Scripta Aterialia, 2005, 53(5): 511-516.
3 Waku Y, Nakagawa N, Wakamoto T, et al. A ductile ceramic eutectic composite with high strength at 1873 K[J]. Nature, 1997, 389(8): 49-52.
4 Sayir A. Directional solidification of eutectic ceramics[M]. Oxford: Oxford University Press, 1999: 1-7.
5 Jose Y Pastor, Javier L Lorca, Alicea Salazar, et al. Mechanical properties of melt‐grown alumina–yttrium aluminum garnet eutectics up to 1900 K[J]. Journal of the American Ceramic Society, 2005, 88(6): 1488-1495.
6 Chen Guoqing, Fu Xuesong, Luo Junting, et al. Effect of cooling rate on the microstructure and mechanical properties of melt-grown Al2O3/YAG/ZrO2 eutectic ceramic[J]. Journal of the European Ceramic Society, 2012, 32(16): 4195-4204.
7 Ma Weidan, Zhang Jun, Su Haijun, et al. Microstructure transformation from irregular eutectic to complex regular eutectic in directionally solidified Al2O3/GdAlO3/ZrO2 Ceramics by laser floating zone melting[J]. Journal of the European Ceramic Society, 2016, 36(6): 1447-1454.
8 Yao Bin, Su Haijun, Zhang Jun, et al. Sintering densification and microstructure formation of bulk Al2O3/YAG eutectic ceramics by hot pressing based on fine eutectic structure[J]. Materials & Design, 2016, 92: 213-222.
9 Nie Ying, Zhang Mingfu, Liu Yang, et al. Microstructure and mechanical properties of Al2O3/YAG eutectic ceramic grown by horizontal directional solidification method[J]. Journal of Alloys & Compounds, 2016, 657: 184-191.
10 Su Haijun, Zhang J, Liu L, et al. Rapid growth and formation mechanism of ultrafine structural oxide eutectic ceramics by laser direct forming[J]. Applied Physics Letters, 2011, 99(22): 221913-221913-3.
11 Fazli R, Fazli M, Golestani-fard, et al. The Effects of raw materials particle size and salt type on formation of nano- cazro3 from molten salts[J]. Ceramics International, 2012, 38(7): 5775-5781.
12 Rahman Fazli, Golestani-Fard F. The effects of processing parameters on molten salt synthesis of CaZrO3, nano-powders using oxide precursors[J]. Powder Technology, 2014, 257(5): 149-155.
13 Rahman Fazli, Golestani-Fard F. Influence of zirconia particle size on the synthesis of CaZrO3 nano-powders from na2co3–nacl molten eutectic salt[J]. Advanced Powder Technology, 2014, 25(5): 1547-1553.
14 Wu Dongjiang, Wang Jiangtian, Niu Fangyong, et al. Microstructure and mechanical property of thin-wall Al2O3–YAG composite ceramics built by laser engineered net shaping[J]. Journal of the Chinese Ceramic Society, 2015, 43(6): 741-746.
吴东江，王江田，牛方勇，等. 激光近净成形Al2O3–YAG复合陶瓷薄壁件微观组织与力学性能分析[J]. 硅酸盐学报，2015，43(6)：741-746.
15 Suffner J, Sieger H, Hahn H, et al. Microstructure and mechanical properties of near-eutectic ZrO2–60wt.% Al2O3 produced by quenched plasma spraying [J]. Materials Science and Engineering: A, 2009, 506(1): 180-186.
16 Zhao Zhongmin, Zhang Long, Zhang Shiyue, et al. Microstructures and mechanical properties of large-scale Al2O3/ZrO2(Y2O3) self-growing ceramic plates prepared by combustion synthesis under high gravity[C]// International Conference on Smart Materials and Nanotechnology in Engineering. International Society for Optics and Photonics, 2007: 64235B-64235B-8.
17 Su Haijun, Zhang Jun, Cui Chunjuan, et al. Rapid solidification behaviour of Al2O3/Y3Al5O12(YAG) binary eutectic ceramic in situ composites[J]. Materials Science and Engineering: A, 2008, 479(1): 380-388.
18 Yao Wenlong, Liu Jing, Troy B Holland, et al. Grain size dependence of fracture toughness for fine grained alumina[J]. Scripta Materialia, 2011, 65(2): 143-146.
19 Miao Pei, Niu Fangyong, Ma Guangyi, et al. Effect of deposition efficiency on microstructure and property of 316L stainless steel fabricated by laser engineered net shaping[J]. Opto- Electronic Engineering, 2017, 44(4): 410-417.
苗佩，牛方勇，马广义，等. 沉积效率对激光近净成形316L不锈钢组织及性能的影响[J]. 光电工程，2017, 44(4): 410-417.
Get Citation: Liu Hanchao, Lu Fan, Ma Guangyi, et al. Effect of constant temperature substrate on microstructure and hardness of Al2O3-based eutectic ceramics[J]. Opto-Electronic Engineering, 2017, 44(12): 1194–1199.
Previous: Fabrication and bacterial adhesion of metal dry electrode with surface microstructure arrays
Next: Picosecond laser microfabrication of infrared antireflective functional surface on As2Se3 glass