TiC对Ti：A1：C=2：2：1系燃烧产物的影响

Ti、Al和C粉的燃烧合成实验结果表明，在Ti：Al：C=2：2：l体系中，添加TiC≤10wt．％时，燃烧产物中Ti3AlC2的含量与未添加TiC的相比，有大幅度增加；添加TiC≥20wt．％时，燃烧产物中Ti3AlC2的含量略有减少，而TiC的含量增多。从燃烧温度的角度探讨了TiC对燃烧合成产物相组成的影响。     

不同气氛和素坯密度对燃烧合成Ti_3AlC_2粉体的影响

实验结果表明 ,Ti:Al:C =2 :2 :1(摩尔比 )体系燃烧合成Ti3AlC2 的环境气氛若为真空 ,燃烧产物主要为TiC ,若为氩气 ,燃烧产物主晶相为Ti3AlC2 ;增加反应物原料的素坯密度 ,可较大程度地提高燃烧产物中Ti3AlC2 的含量。     

添加Ti_3AlC_2和NH_4Cl对燃烧合成Ti_3AlC_2的影响

Ti、Al和C组成的Ti:Al:C=2:2:1(摩尔比)系的燃烧合成产物主要物相为Ti_3AlC_2,在体系中添加Ti_3AlC_2形核后,Ti_3AlC_2的生成量增多,有利Ti_3AlC_2的燃烧合成;添加固体NH_1Cl,燃烧合成产物主要物相为TiC,不利于燃烧合成Ti_3AlC_2,并从热力学的角度作了解释.     

自蔓延高温合成层状Ti_3SiC_2陶瓷的相形成过程

采用自蔓延高温合成方法,以Ti、Si、C粉为原料合成了层状Ti3SiC2陶瓷材料,用X射线衍射分析了燃烧合成产物的相组成,并结合反应物体系的差热分析和X射线衍射分析探讨了自蔓延高温合成Ti3SiC2的相形成过程,进而建立Ti-C-Si体系在自蔓延燃烧合成反应过程的物理模型.     

TiC1-xNx燃烧合成的反应动力学研究

基于差热测试、淬熄实验、微观组织及化学成分分析,研究了TiO2-Mg-C-N2体系燃烧反应机理.结果表明,该反应过程经由多个中间反应直至最后完成,Mg在650℃时开始熔化,TiO2和Mg在750℃左右开始发生剧烈的氧化还原反应,Ti和C、N2在1100℃发生反应,TiC和TiN在1300℃固溶合成TiC11-xNx.TiO2-Mg-C-N2体系燃烧反应为复杂的固-液-气反应,其过程为:TiO2颗粒与Mg熔体以溶解-析出机制反应生成Ti和MgO;反应放出的强热诱发Ti-C-N2之间的反应,以扩散反应机制生成TiC和TiN;TiC和TiN连续固溶生成TiC1-xNx固溶体.     

YSZ/Al_2O_3复合陶瓷的制备及性能研究

选用ZrO2（5wt．％Y2O2）和Al2O2为粉体原料,采用溶胶凝胶法制备氧化锆基氧化铝（YSZ／Al2O3）复合陶瓷,研究了悬浮体的Zeta电位、分散性、流变性及其显微结构．结果表明：在pH=9～10附近、选用SD-00为分散剂,加入量为1．0wt．％,粉体最佳配比为70wt．％ZrO2（5wt．％Y2O2）和30wt．％Al2O3获得固相含量为50Vol．％的悬浮体,制备出了均匀致密、高强度的YSZ／Al2O3复合陶瓷．     

LaO2对Al2O3-TiCp/Al基复合材料组织结构的影响

利用Al-TiO2-C体系熔铸法制备含稀土LaO2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体系的组织结构进行了详尽的分析,讨论了稀土LaO2铝对Al2O3-TiCp/Al基复合材料的影响规律。实验结果表明,稀土LaO2的加入可改善陶瓷颗粒Al2O3和TiC与熔体的润湿性,而且有效细化和净化了组织,降低了反应温度。稀土LaO2添加剂含量为0,5％时利用熔铸法制备的复合材料中原位形的Al2O3,TiC颗粒尺寸较小,分布均匀。     

(TiB_2-TiC)_pNi/TiAl/Ti梯度材料的制备及性能分析

采用电场激活压力辅助燃烧合成技术(FAPAS)制备了功能梯度材料(TiB2-Ti )pNi/TiAl/Ti。界面微观分析表明:Ti粉和B4C粉原位合成了(TiB2-TiC)pNi复合陶瓷,Ti粉和Al粉反应生成了中间层TiAl,TiAl与其两侧的复合陶瓷和钛板均实现了良好连接;(TiB2-TiC)pNi复合陶瓷晶粒细小均匀,TiB2和TiC颗粒均匀地分布在Ni基体中。剪切实验表明:试样的剪切强度随施加电流和压力的增大而增大,剪切强度最大达到了85.78 MPa。对断裂界面的SEM分析表明,断裂裂纹发生在(TiC-TiB2)pNi复合陶瓷与TiAl的连接界面处。通过FAPAS方法合成梯度材料过程中,高温下增大电流可以有效促进界面间的扩散,从而提高界面的连接强度,而压力能够细化复合陶瓷的晶粒,使晶粒变细,对梯度材料强度提高也有一定的促进作用。     

LaO_2对Al_2O_3—TiC_p/Al基复合材料组织结构的影响

利用Al-TiO2-C体系熔铸法制备含稀土LaO2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体系的组织结构进行了详尽的分析,讨论了稀土LaO2铝对Al2O3-TiCp/Al基复合材料的影响规律。实验结果表明,稀土LaO2的加入可改善陶瓷颗粒Al2O3和TiC与熔体的润湿性,而且有效细化和净化了组织,降低了反应温度。稀土LaO2添加剂含量为0,5％时利用熔铸法制备的复合材料中原位形的Al2O3,TiC颗粒尺寸较小,分布均匀。     

Fe3Al/TiC复合材料的高温抗氧化性能

研究了Fe_3Al/TiC复合材料的高温抗氧化性能。结果表明:Fe_3Al/TiC复合材料在950℃的氧化动力学特征均近似服从抛物线规律,并且随TiC含量增加,Fe_3Al/TiC复合材料的高温抗氧化性能降低。     

Hydrogenation properties of mechanically milled Mg2Ni0.8Cr0.2-CoO／Al2O3 composites

INTRODUCTION Mg-based alloys are considered as potentialcandidates for hydrogen storage materials because oftheir large hydrogen capacity (Reilly and Wiswall,1968; Pedersen and Larsen, 1993). However, asMg-based alloys desorb hydrogen at temperatureshigher than 600 K, they are not applicable to practicaluse. Many researches have studied to improve hy-driding/dehydriding kinetics and to lower the workingtemperature (Wang et al., 2002; Tsushio et al., 1998;Spassov and K?ster, 1998; Orim…     

Hydrogenation properties of mechanically milled Mg2Nio.8Cr0.2-CoO/Al2O3 composites

Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.     

AlTiCCeP对Al-30%Si合金初晶硅相的变质效果研究

借助SEM与XRD分析手段,对自制的AlTiCCeP(含2%P)中间合金进行物相分析,并以Al-30%Si合金为变质对象,探讨其对初晶硅的变质效果与变质机理。结果发现:AlTiCCeP中间合金组织中含有TiC、AlP、TiAl3和Ti2Al20Ce等物相,当AlTiCCeP的添加量(以磷的实际添加量计算)为Al-30%Si合金质量的0.15%时,对初晶硅变质效果显著,平均尺寸约为28μm,优于商用Cu-P中间合金。     

Ti-IF钢在铁素体区热轧的析出物研究

通过透射电镜，观察了IF钢在铁素体区轧制时不同轧制工艺对析出物的形貌、大小、分布和数量方面的影响。结果发现：不同轧制工艺下的析出物基本上都是由TiN、TiS、Ti4C2S2和TiC组成，并且随着开轧温度的升高，析出物的总体平均尺寸减小，较小尺寸的二相粒子数量增多。     

ZTA-SiCw-TiC复相陶瓷的制备和表征

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表面改性提高与Ti6A14V对磨材料UHMWPE摩擦学性能

Surface engineering has been emerging as one of the most promising technologies to improve the tribological properties of biomaterials with a view to extending the life span of medical implants. For example, some novel surface engineering techniques including ion implantation of ultra-high molecular weight polyethylene (UHMWPE) and thermal oxidation (TO) treatment of titanium alloy have been developed. However, the full potential of improving the wear resistance of orthopaedic implants based on the UHMWPE/ Ti6A14V system will not be realized until the tribological performance of this surface engineered tribo-system is fully characterized and the acting wear mechanisms are well understood. In this paper, a pin-on-disc tribometer was employed to evaluate the tribological response of the following three tribo-systems: (1) untreated UHMWPE/untreated Ti6A14V. (2) untreated UHMWPE/TO-treated Ti6A14V and (3) ion implanted UHMWPE/TO treated Ti6A14V under water lubricated conditions. Experimental results show that the tribological properties of UHMWPE can be significantly increased by surface enghmering its surface and/or the counterface. Tiffs can be attributed to the hardened surface of UHMWPE via molecular structure modification induced by ion bean bombardment coupled with the surface oxide layer on Ti6A14V formed during TO treatment, which has favorable tribological compatibility with UHMWPE.