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排序方式: 共有299条查询结果,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2019,44(55):29371-29379
The paper analyzes the effect of electrolytic hydrogenation on martensite transformation temperatures in binary TiNi alloys. The analysis shows that this effect can be strong or weak depending on the phase state of TiNi. Research data are presented on the diffusivity of hydrogen in binary TiNi alloys in martensite and austenite states. The diffusion coefficient of hydrogen is estimated from its distribution measured by glow discharge spectroscopy in TiNi after hydrogenation. The experimental results about the formation of TiNiH hydride in the martensitic and austenitic state in binary TiNi based alloys are also presented. 相似文献
2.
TiNi表面磁控溅射DLC薄膜的纳米压痕与摩擦性能 总被引:1,自引:0,他引:1
采用室温磁控溅射技术在TiNi合金表面制备出DLC/SiC(类金刚石/碳化硅)双层薄膜(SiC为中间层),采用拉曼光谱仪、纳米压痕仪和球-盘式摩擦磨损仪研究DLC薄膜的结构、纳米压痕和摩擦性能.结果表明:制备的DLC/SiC薄膜石墨含量高、纳米硬度(5.493 GPa)低、弹性模量(62.2447 GPa)低.在以氮化硅球(半径为2mm)为对摩件,4.9N载荷、室温、Kokubo人体模拟体液润滑下,该DLC/SiC薄膜具有低且稳定的摩擦因数,其平均值约为0.094. 相似文献
3.
TiNi合金激光焊接接头形状恢复温度的研究 总被引:1,自引:0,他引:1
利用热模拟试样模拟TiNi合金激光焊接接头焊缝热影响区,对焊接接头、焊缝金属、模拟热影响区和母材的相变温度进行差热分析,研究了焊接接头与其它三者逆相变温度的关系,并利用OM,SEM和XRD对母材、热影响区和焊缝金属的组织、析出相的分布以及晶体结构进行了研究.结果表明,TiNi合金激光焊接接头的形状恢复率与母材无明显差别,但形状恢复温度区间与母材差异较大,其形状恢复开始温度比母材低40℃;焊缝金属和热影响区逆相变开始温度(As)和结束温度(Af)均不同于母材,主要原因是焊缝金属经历了熔化-凝固过程,失去了母材中原有的晶体择优取向,且析出相尺寸小、分布不均;而热影响区As和Af降低,可能是细小析出相重新固溶于基体所致.整个接头的逆相变温度区间与焊缝金属近似,调控焊缝金属的相变温度是控制TiNi合金激光焊接接头形状记忆功能的关键. 相似文献
4.
大塑性变形技术制备块状超细晶TiNi基形状记忆合金研究进展 总被引:1,自引:0,他引:1
详细介绍了块状超细晶TiNi基形状记忆合金的研究进展,包括其制备工艺与显微组织、马氏体相变行为、力学性能和形状记忆特性以及超弹性性能,并介绍了其在医学和工程领域的实际应用,最后探讨了块状超细晶TiNi基形状记忆合金今后的研究发展方向。 相似文献
5.
采用两步法成功制备了新型钛镍合金Ti Ni45V8In0.2,并进行XRD、SEM以及力学性能、抗应力松弛性能和耐腐蚀性能的测试与分析。结果表明:该新型合金由网状Ti Ni母相和弥散分布的V3Ni相组成,具有较佳的力学性能、抗应力松弛性能和耐腐蚀性能。与常规Ti Ni合金相比,新型合金的-40、25℃和150℃抗拉强度分别增加47.1%、39.4%、123.9%;-40、25℃和150℃屈服强度分别增加110.3%、92.5%、263.8%;腐蚀电位正移267 m V;50 h后的应力松弛从16%减小至0.5%。 相似文献
6.
7.
Effect of compressive stress aging on transformation strain and microstructure of Ni-rich TiNi alloy
Jin-Feng Li Zi-Qiao Zheng Xi-Wu Li Shi-Chen Li 《Materials Science and Engineering: A》2009,523(1-2):207-213
The Ti–50.7%Ni (atom fraction) alloy rods were compressive stress aged at 400 °C, 450 °C and 500 °C for different time, their strain behaviors accompanied by temperature elevation were investigated, and their microstructures were observed. It is found that the compressive stress aged TiNi alloy rod displays an obvious contractive strain behavior in the stress direction as the temperature is elevated from approximately 55–75 °C. Compressive stress causes the parallel alignment of the aging precipitate Ti3Ni4 in the TiNi alloy, which controls the martensitic transformation (B19′ transformation) and its reverse transformation, leading to its contractive strain behavior accompanied by temperature elevation. The contractive strain of the TiNi alloy compressive stress aged at 400 °C for 100 h is increased with increasing compressive stress up to 140 MPa. Higher aging temperature and longer aging time lead to the coarsening of the precipitates and the enlarging of the inter-precipitate spacing, and therefore result in a decrease in the contractive strain. 相似文献
8.
Z. ZlatanovaT. Spassov G. EggelerM. Spassova 《International Journal of Hydrogen Energy》2011,36(13):7559-7566
Mg2Ni-TiFe and Mg2Ni-TiNi nanocomposites were prepared by milling for a short time of two preliminary milled to a nanocrystalline state hydrogen absorbing phases, Mg2Ni and TiFe or Mg2Ni and TiNi. The milling results in a sufficient density of contacts between the fine powder particles with different composition. The presence of a large amount of such inter-particles contacts leads to lowering of the initial temperature of the composites gas phase hydriding, as in the same time the temperature range of hydriding is enlarged, compared to the composites components.On the grounds of the proved low temperature hydriding (≤200 °C) of the nanocomposites, taking place with appropriate kinetics, the possibility for improved electrochemical hydriding was checked, exploiting the idea for charging Mg2Ni particles through the contacts with TiFe/TiNi. In this way we are supposed to achieve more complete electrochemical hydriding of the Mg2Ni particles, which are usually only superficially hydrogenated at room temperature, mainly due to the low diffusion coefficient of hydrogen in the Mg2Ni crystal lattice and corrosion processes in strong alkaline solutions. The achieved discharge capacity for the Mg2Ni-TiFe composite is essentially higher compared to that of the mechanical mixture of the two composite’s components. 相似文献
9.
10.
It has been established that the superelastic effect of TiNi alloy is related to a reversible martensitic transformation; that is, stress-induced transformation. The high elastic recovery of TiNi alloy has made it a potential candidate for high wear resistance applications. In the present study the tribological behavior of superelastic TiNi alloy was studied and compared to Ni, Ti, and AISI 304 stainless steel using dry sliding wear and friction tests. The effect of normal load and testing temperature on superelasticity has been investigated. It has been found that although AISI 304 stainless steel and superelastic TiNi alloy have similar hardness, TiNi exhibits superior wear resistance. The wear rate of AISI 304 stainless steel is over four times higher than TiNi. The superior wear resistance of TiNi and the effect of load and temperature on wear were discussed and related to the reversible martensitic phase transformation, as well as self-accommodation and stabilization of martensite. 相似文献