利用热压法制备了具有较为显著织构的磷酸镧(LaPO_4)陶瓷,利用X-射线衍射(XRD)表征了样品的织构,与扫描电镜(SEM)观察结果相一致,样品的织构可能是LaPO_4晶粒板面((200)面)沿着垂直于加压方向旋转以及择优生长共同作用的结果.LaPO_4陶瓷的硬度和断裂韧性具有较为明显的各向异性,而弹性模量则不明显,其中对于断裂韧性而言,在平行于加压方向样品表面,与加压方向呈0°方向的断裂韧性为呈90°方向的1.75倍,这主要是由于LaPO_4陶瓷的板面((200)面)沿着垂直于加压方向择优取向,从而与加压方向呈0°方向裂纹扩展时偏转角度更大,最终造成其断裂韧性也更大.
Lanthanum phosphate (LaPO_4) ceramics with marked preferred orientation were fabricated by hot-pressing sintering. X-ray diffraction was used to demonstrate the texture of LaPO_4 ceramics, whose result is consistent with SEM observation, which may be due to the combination of the grains ((200) planes) rotation and preferential grain growth. There is fairly hardness and indentation fracture toughness anisotropy in the hot-pressing LaPO_4 ceramics, but little anisotropy in elastic modulus. The ratio of maximum to minimum fracture toughness is about 1.75 times in the as-obtained LaPO_4 ceramics due to the preferred orientation of laminated structure of LaPO_4 ceramics. The higher crack deflection angles may play the key role for the higher fracture toughness in the orientation of 0° relative to the hot-pressing direction than that of 90° in the plane normal to the pressing direction.
参考文献
| [1] | Morgan PED.;Marshall DB. .CERAMIC COMPOSITES OF MONAZITE AND ALUMINA[J].Journal of the American Ceramic Society,1995(6):1553-1563. |
| [2] | Marshall DB.;Housley RM.;Cheung JT.;Morgan PED. .High-temperature stability of the Al2O3-LaPO4 system[J].Journal of the American Ceramic Society,1998(4):951-956. |
| [3] | Hikichi Y et al.[J].Journal of the American Ceramic Society,1987,70(10):C252. |
| [4] | R. S. Hay .(120) and (12 2-bar) monazite deformation twins[J].Acta materialia,2003(18):5255-5262. |
| [5] | R. S. Hay;D. B. Marshall .Deformation twinning in monazite[J].Acta materialia,2003(18):5235-5254. |
| [6] | Wang J Y et al.[J].Applied Physics Letters,2005,87(05):051902. |
| [7] | Wang R G et al.[J].Materials Letters,2002,57(04):822. |
| [8] | Wang R G et al.[J].Ceramics International,2003,29(01):19. |
| [9] | Davis JB.;Housley RM.;Morgan PED.;Marshall DB. .Machinable ceramics containing rare-earth phosphates[J].Journal of the American Ceramic Society,1998(8):2169-2175. |
| [10] | Wang RG.;Pan W.;Chen J.;Fang MH.;Cao ZZ.;Luo YM. .Synthesis and sintering of LaPO4 powder and its application[J].Materials Chemistry and Physics,2003(1):30-36. |
| [11] | Anstis G R et al.[J].Journal of the American Ceramic Society,1981,64(09):533. |
| [12] | Asmani M et al.[J].Journal of the European Ceramic Society,2001,21(08):1081. |
| [13] | Kim W.;Cho DH.;Kim YW. .Texture and fracture toughness anisotropy in silicon carbide[J].Journal of the American Ceramic Society,1998(6):1669-1672. |
| [14] | Lee F et al.[J].Journal of the American Ceramic Society,1992,75(07):1748. |
| [15] | Liu H et al.[J].Journal of the American Ceramic Society,1989,72(04):559. |
| [16] | Faver K T et al.[J].ACTA METALLURGICA,1983,31(04):565. |
| [17] | Faver K T et al.[J].ACTA METALLURGICA,1983,31(04):577. |
| [18] | Becher P F .[J].Journal of the American Ceramic Society,1991,74(02):255. |
| [19] | 王瑞刚 et al.[J].无机材料学报,1998,27(01):87. |
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