Gu Y W, Loh N H, Kho K A, Tor S B, Cheang P
School of Mechanical and Production Engineering, Nanyang Technological University, Singapore, Singapore.
Biomaterials. 2002 Jan;23(1):37-43. doi: 10.1016/s0142-9612(01)00076-x.
Dense hydroxyapatite (HA) compacts have been successfully fabricated by a spark plasma sintering (SPS). The sintering behavior of HA powders at different temperatures ranging from 850 degrees C to 1100 degrees C was studied. Results showed that spark plasma sintering resulted in rapid densification to near theoretical density. The HA compact was homogeneously sintered at 950 degrees C in a short sintering duration of 5 min, while maintaining high quality and high relative density (>99.5%). The density, microhardness and Young's modulus of HA sintered compact initially increased with the sintering temperature, reached a maximum value at around 950-1000 degrees C, then decreased with further increase in the temperature due to the decomposition of HA into beta-tricalcium phosphates. Fracture toughness results showed no significant difference with increasing temperature due to the combined influences of density and grain size. Microstructure analysis showed no noticeable grain growth under different sintering temperatures due to the short time exposure at high temperatures.
通过放电等离子体烧结（SPS）已成功制备出致密的羟基磷灰石（HA）坯块。研究了HA粉末在850℃至1100℃不同温度下的烧结行为。结果表明，放电等离子体烧结导致快速致密化至接近理论密度。HA坯块在950℃下于5分钟的短烧结时间内均匀烧结，同时保持高质量和高相对密度（>99.5%）。HA烧结坯块的密度、显微硬度和杨氏模量最初随烧结温度升高而增加，在950 - 1000℃左右达到最大值，随后由于HA分解为β - 磷酸三钙，温度进一步升高时其值下降。断裂韧性结果显示，由于密度和晶粒尺寸的综合影响，随温度升高无显著差异。微观结构分析表明，由于在高温下暴露时间短，不同烧结温度下未观察到明显的晶粒生长。
