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放电等离子烧结制备Ti3SiC2材料的研究 总被引:5,自引:0,他引:5
本文报道分别以Ti/Si/C,Ti/SiC/C为原料,采用放电等离子烧结工艺制备Ti3SiC材料的研究结果,以元素单质粉为原料,掺加适量Al作助剂能加速Ti3SiC2的反应合成并提高材料的纯度,在1200-1250℃的温度下能制备出经XRD,SME和EDS表征不含TiC和SiC等杂质相的纯净Ti3SiC2材料,而以Ti/SiC/C为原料时,有无Al作助剂都难以制备出纯净的Ti3SiC2,其反应合成温度明显高于以元素单质粉为原料的。 相似文献
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以铝为助剂结合放电等离子烧结工艺,在较低温度下快速制备出高纯致密Ti3SiC2块体材料.掺加适量铝能加快Ti3SiC2的反应合成,提高制备材料的纯度,并促进Ti3SiC2晶体的生长和材料的快速烧结致密.在升温速率为80℃/min,z轴压力为30MPa时,材料制备的最佳温度为1250~1300℃.所制备材料经XRD、SME和EDS分析表明不含TiC和SiC等杂质相,Ti3SiC2为5~15μm的板状结晶,断裂韧性为6.8±0.2MPa·m1/2,弯曲强度为420±10MPa. 相似文献
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放电等离子烧结制备致密TiAl/Ti2AlC复合材料 总被引:4,自引:0,他引:4
本研究以Ti/Al/TiC为原料,采用放电等离子烧结工艺制备致密TiAl/Ti2AlC复合材料。制备材料主要由TiA1和Ti2AlC两相组成。当原料中掺人体积分数为7%的TiC时,Ti-A1基体由γ相和层状相所构成,而Ti2AlC颗粒则均匀分布在基体中。经热处理后,则转变为Ti2AlC颗粒均匀分布在由γ相构成的基体中的结构。研究中还测定了所得复合材料的断裂韧性和弯曲强度。 相似文献
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以Ti和C的片状材料为原料, 利用放电等离子烧结(SPS)技术烧结制备了具有层状结构特征的Ti/C叠层复合材料, 研究了不同烧结温度下的叠层材料的组织形貌和室温力学性能。研究结果表明: 随烧结温度的升高, 反应层的厚度增大, 烧结温度达到1500℃时, 反应层的厚度可达到32.6 μm, 进一步提高烧结温度, 将会使Ti发生熔化现象, 无法得到Ti/C叠层复合材料。当烧结温度达到1500℃和1510℃, 层状复合材料的抗弯强度和断裂功分别达到最大值1571.51 MPa和215.09×103 J/m2。Ti/C叠层复合材料的裂纹扩展路径主要有裂纹偏转、 裂纹并行扩展和裂纹尖端的分叉钝化, 这些扩展路径是叠层材料增韧的主要机制。 相似文献
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应用放电等离子烧结技术(SPS)制备新型SPS NdFeB磁体.利用扫描电子显微镜(SEM)观察磁体的显微组织,利用B-H回线仪测量磁体磁性能,利用阿基米德法测量样品密度.系统研究了稀土含量不同的两种NdFeB磁体的烧结特征.结果表明,SPS NdFeB磁体的烧结特征与传统烧结方式的特征不同,且与样品稀土含量密切相关;... 相似文献
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The effect of aluminum on synthesis of Ti3SiC2 by spark plasma sintering (SPS) from elemental powders was investigated in this paper. X-ray diffraction patterns and scanning electron microscopy photographs of samples with different content of aluminum indicated that proper addition of aluminum both favored the formation and accelerated the crystal growth of Ti3SiC2. The process parameters in the sintering course revealed that addition of aluminum decreased the temperature for the synthesis reaction of Ti3SiC2. Polycrystalline bulk Ti3SiC2 material with high purity and density could be fabricated by spark plasma sintering from the elemental powder mixture with starting composition of Ti3Si1–xAlxC2, where x = 0.05–0.2. SEM photographs showed Ti3SiC2 synthesized from elemental powders was in plane-shape with a size of about 10–20 µm in the elongated dimension. Solid solution of aluminum decreased the thermal stability of Ti3SiC2 and made the temperature at which Ti3SiC2 decomposed be as low as 1300°C. 相似文献
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Um Tae-Young Abe Toshihiko Sumi Shinichi 《Journal of Materials Synthesis and Processing》1999,7(5):303-309
The characteristics of spark plasma sintering, a new method of powder processing, were investigated. Four systems of intermetallic compounds—Ti-Al, Ti-Al-Cr, Mo-Si, and Mo-Si-Nb—were fabricated, and the formation process of compounds, the formed phases, and the microstructure of samples were observed. During the sintering of all the compositions of mixed powders, most of the compounds were formed by combustion reaction which occurred at almost the same temperature as the conventional combustion reaction temperature. The fabricated samples were well densified, however, the relative densities of the Mo-Si samples were lower than the Ti-Al samples. Ultrasonic images show that no internal defects were found in any sample and the grain size became finer with the increase in the Cr content in the Ti-Al system and Nb content in the Mo-Si system. The formed phases of Ti:Al=1:1 composition samples were TiAl and Ti3Al phases, and Ti-Al added Cr samples consisted of TiAl, Ti3Al, Cr2Al, and Cr9Al17 phases. The sample synthesized with Mo:Si=1:2 mixed powders had only MoSi2 phases, and Mo-Si samples with added Nb consisted of four phases: MoSi2 with a small amount of Mo5Si3 phases in the matrix and Nb5Si3 with unreacted Nb for dispersed phases. 相似文献
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放电等离子超快速烧结氧化物陶瓷 总被引:15,自引:6,他引:15
本文介绍一种氧化物陶瓷超快速烧结的新方法.用放电等离子烧结的方法对Al2O3、Y-TZP、YAG、Al2O3-ZrO22和莫来石等各种氧化物粉体进行了超快速烧结,采用2~3min升温到1200℃以上,不保温或保温2min,然后迅即在3min之内冷却至600℃以下的烧结温度,得到了直径为20mm的晶粒细、致密度高、力学性能好的烧结样品.对用化学共沉淀法自制的20mol%Al2O3-ZrO2(3Y)纳米粉体分别在1170~1500℃之间的7个不同温度下进行放电等离子烧结,升温速率为200℃/min,保温2min后;迅即在3min之内强制冷却至600℃以下.1350℃以上烧结得到的样品密度已接近理论密度,1250℃以上烧结得到的样品的断裂韧性K1c都大于6MPa·m1/2放电等离子超快速反应烧结所得到的ZrO2-莫来石复相陶瓷致密度高、力学性能好,ZrO2晶粒在莫来石基体中分布均匀,XRD结果表明,在1530℃烧结的样品中,已找不到ZrsiO4痕迹,说明在如此快速的烧结条件下;反应烧结已经可以完成. 相似文献
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钙硅基生物陶瓷具有良好的生物活性和细胞相容性, 在生物医疗领域具有广阔的发展前景。但是其粉体烧结性能差的缺点导致很难获得致密的陶瓷材料, 阻碍了其应用的进程。本研究采用化学共沉淀法制备了纯度高且烧结活性好的镁黄长石粉体, 然后采用放电等离子烧结技术(SPS)制备了镁黄长石陶瓷材料。通过X射线衍射(XRD)和扫描电子显微镜(SEM)表征了样品的组成结构和显微形貌, 并通过阿基米德法和模拟体液浸泡法分析了镁黄长石陶瓷样品的致密度和生物活性。研究结果表明, 采用SPS技术在1170℃、70 MPa保温5 min条件下可获得致密度超过99%的镁黄长石陶瓷材料。在模拟体液中浸泡3 d, 陶瓷样品表面出现磷酸盐的沉积, 浸泡7 d后生成了类骨羟基磷灰石, 说明SPS技术制备的致密镁黄长石生物陶瓷具有良好的诱导沉积类骨磷灰石能力。 相似文献