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采用SHS/PHIP工艺制备了致密的TiC-Al2O3-Fe系金属陶瓷,研究了延迟时间,高压特续时间,压力及Fe含量对合成TiC-Al2O3-Fe金属陶瓷实度的影响,结果表明,采用SHS/PHIP技术制备了TiC-Al2O3-Fe系金属陶瓷时,合成产物中气体的排放,液相的存在及组成相之间的润湿性是制备密实材料的关键。 相似文献
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Fe-Ti-C系燃烧合成反应的热力学分析 总被引:5,自引:0,他引:5
利用相图计算技术(CALPHAD)对Fe-Ti-C燃烧合成反应体系进行热力学分析,着重研究Fe含量和C/Ti原子比对体系绝热燃烧温度Tad和平衡相组成的影响.研究结果表明,Fe含量对 Fe-Ti-C三元系的平衡相组成影响不大,但对绝热燃烧温度的影响非常大.当保持C/Ti原子比接近1.0时,不管Fe含量如何变化;在298K下均会得到理想的平衡相组织TiC+Fe 随Fe含量增加,体系的绝热燃烧温度大致呈线性降低.Fe-Ti-C体系发生SHS反应的热力学条件之一(Tad>1800K)是Fe<55wt%.而 C/Ti原子比对绝热燃烧温度的影响比较小,但对平衡相组成影响非常大,主要表现在两个方面:①石墨相的析出温度不同.随C/Ti原子比降低,析出温度也随之降低.②在各温区石墨相的含量不同.当 C/Ti在1.0~1.4变化时,石墨相含量在低温区由1%提高到16%. 相似文献
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一种新型陶瓷材料及其耐磨性 总被引:5,自引:0,他引:5
对新型Al2O3-TiC-Co陶瓷的磨粒磨损,冲蚀磨损及其在单颗粒作用下的摩擦磨损行为进行了研究。与AT30(70wt%Al2O3-30wt%TiC)陶瓷相比,Al2O3-TiC-Co陶瓷具有更为良好的耐磨性,金属钴的存在提高了基体的韧性,细化了晶粒,其综合力学性能得到了显著提高,ATC陶瓷样品耐磨性与其强韧化水平和细致的组织结构有关。 相似文献
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通过自蔓延高温合成结合准热等静压法(SHS/PHIP)制备出了致密度为97.7%的TiC-Al2O3-20Fe3合金陶瓷(TAF20),分析了金属陶瓷的相组成、微观组织及性能。结果表明:金属陶瓷由TiC,Al2O3陶瓷颗粒和Fe粘结相组成;粘结相中Fe与Al2O3之间的界面光滑,与TiC之间有一薄的扩散层;TAF20金属陶瓷的抗强度和抗压强度分别为890MPa和18.4GPa。 相似文献
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Al-Ti-TiO2体系自蔓延高温合成及机理 总被引:1,自引:0,他引:1
采用自蔓延高温合成技术制备了TiAl/Al2O3复合材料,研究了原料配比对合成过程及产物特征的影响,结果表明,随着Al2O3含量的增加,燃烧温度和燃烧速度均增大,材料的致密度得到改善。Al2O3颗粒尺寸小于1μm,分布于基体交界处,有一定程度的团聚。通过差热分析研究了Al-Ti-TiO2体系反应过程,发现Al-TiO2还原较晚开始,但由于激活能低而速度较快,因此较早完成,TiAl3最早生成,但只作为中间产物存在,随后向TiAl和TiAl3相转变的过程为控制环节,其激活能也体现为总反应的激活能。 相似文献
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Jixin CHEN Jialin LI Yanchun ZHOU Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang China 《材料科学技术学报》2006,22(4):455-458
Ti3AlC2/TiC-Al2O3 composite was synthesized by a combustion reaction in TiO2-Al-C system. The effect of the compositions in raw materials on the products was investigated. Ti3AlC2/TiC-Al2O3 composite was obtained at the molar ratio of TiO2:Al:C=3.0:5.0~5.1:1.8~2.0. The reaction path for the 3TiO2-5Al-2C system was proposed. Al3Ti, Ti2O3, TiO, and δ-Al2O3 are found to be transitional phases. Finally,Ti3AlC2/TiC-Al2O3 composite forms at ~900℃ of furnace temperature. The measured Vickers hardness,fracture toughness, and flexural strength of the nearly dense sample from 3TiO2-5Al-2C are 13.3±1.1 GPa,5.8±0.3 MPa.m1/2, and 466±39 MPa, respectively. 相似文献
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采用熔铸法制备了原位自生Al2O3-TiCp/Al基复合材料。借助差示扫描量热仪(DSC)、扫描电子显微镜(SEM)、能谱分析仪(EDS)、X射线衍射仪(XRD)等测试技术,对Al-TiO2-C体系的热力学进行了详尽的分析,讨论了过量铝对Al-TiO2-C体系反应的影响。结果表明,通过控制反应温度等工艺参数完全可以获得原位自生Al2O3-TiCp/Al基复合材料,避免副产物Al3Ti和Al4C3的产生。Al-TiO2-C体系原位合成Al2O3-TiCp/Al基复合材料存在着复杂的化学反应。首先在无过量铝的情况下,Al与TiO2发生置换反应,生成了Al2O3和游离态[Ti],而后游离态[Ti]与C结合生成TiC;而存在过量铝的情况下,首先发生铝热反应生成Al3Ti,进而Al3Ti与C结合生成TiC。最终完全获得Al2O3-TiCp/Al复合材料。随着过量Al含量由0增加至70%,Al与TiO2反应生成Al2O3的反应起始温度不断降低。 相似文献
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Microstructure and interface reactions of Al2O3 joints brazed by Cu-Zn-Ti alloy were studied by using SEM, EDS and XRD. The effects of brazing temperature and Ti content on interfacial reactions and microstructure were investigated, and the action of adding Zn into brazing alloy was also studied. TiO, Ti3Al and CuTi were formed at the interface of ceramics and the filler metal, while CuTi, Cu3Ti and alpha -Cu were found in the brazing. The thickness of the reaction layer increased with increasing of brazing temperature, under the same brazing process, the thickness increased with the Ti content. 相似文献
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The reaction of CuCl with silicon containing as impurities Al, Fe, Ca and Ti or with some silicides (Si2Ca, Si2Fe, Si2Ti) has been investigated in the temperature range 250–310 °C. For the reaction between CuCl and commercial Si, it has been found that at 282 °C, the aluminium promotes the reaction between Cu3Si and CuCl while its rate of consumption is greatly decreased by the presence of iron impurity. The combined action of these two impurities improves the quantity of the copper-silicon alloy formed. In the presence of silicides, the reaction with CuCl leads to copper formation with a high degree of dispersion. 相似文献
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《Materials Science & Technology》2013,29(6):667-672
AbstractThe formation of Ti3AlC2 was first investigated by mechanically induced self-propagating reaction (MSR) in Ti–Al–C system at room temperature. The effects of the milling parameters on the formation of Ti3AlC2 were discussed. The phase composition and microstructure were analysed and observed by using X-ray diffraction and scanning electron microscopy, respectively. The formation mechanism of Ti3AlC2 was analysed. An MSR was ignited during mechanical alloying of Ti, Al and C powders after a short time. An exothermic reaction between Ti and Al in the Ti–Al–C system first occurred after a certain milling time. Then, Ti–C reaction was induced at high temperature. All of the above reactions were exothermic that resulted in Ti–Al liquid formation. The previously formed TiC dissolved into and nucleated in the Ti–Al liquid. At last, Ti3AlC2 formed between the Ti–Al melt and the TiC. The final products consist of Ti3AlC2, TiC and Al3Ti. 相似文献
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Ti/A1N快速退火界面反应的实验研究 总被引:1,自引:0,他引:1
在电子封装用的A1N陶瓷多晶衬底上生长250nm的Ti膜,并进行快速退火。用RBS(卢瑟福背散射)、AES(俄歇电子能谱)、SIMS(二次离子质谱)和XRD(X射线衍射)等实验技术对界面反应进行了分析研究,用划痕实验测量了退火对Ti/A1N界面粘附力的影响。实验结果表明:快速退火时,Ti,A1,N以及A1N中掺杂的O均发生明显的界面扩散和界面反应。样品表面的O和A1N衬底中掺杂的O都向Ti膜中扩散,在较低的退火温度下生成TiO2;在较高的退火温度下与扩散到Ti膜中的A1反应,在Ti膜中间形成Al2O3层。N向Ti中扩散,并与Ti反应生成TiN。在薄膜和衬底之间有Ti的氧化物生成。粘附力的测量结果表明:在较低的温度下进行快速退火可以明显提高Ti/A1N界面的强度,在较高的温度下,界面强度有所下降。 相似文献