钛合金TC-4在高应变率下的动态本构关系

利用分离式Hopkinson扭杆对钛合金TC-4进行了高应变率下动态剪切本构关系的实验研究。结果表明TC-4对应变率高度敏感,对应变率的敏感性随应变率的提高而增加。其动态应力应变关系呈线性强化形式。但动态强化模量随应变率的提高而略有减少。采用Malvern给出的过应力模式_p={exp[(1/)(-f())]-1}/b可以较好地描述TC-4的动态剪切本构关系。     

Investigation on ultrasonic cavitation erosion of TiMo and TiNb alloys in sulfuric acid solution

Two kinds of Ti-alloys, i.e., TiMo and TiNb alloys are manufactured in this paper, and their ultrasonic cavitation erosion behaviors in 0.1 M H₂SO₄ solution are evaluated by the mean depth erosion (MDE), SEM and white light photograph. The results show that MDE of TiMo and TiNb alloys obviously increase with increasing the cavitation erosion time, however, they evidently decrease with the increment of Mo or Nb content at each fixed cavitation erosion time, and even some large blank areas (uneroded areas) still exist on the sample surface after ultrasonic cavitation erosion for 2 h in the case of Ti10Mo and Ti20Nb samples, implying the enhanced anti-cavitation erosion property of Ti-alloy by adding Mo or Nb element. The MDE of Ti10Mo or Ti20Nb sample is lower than that of TC4 sample in the case of each cavitation erosion time, indicating the better cavitation erosion resistance of of Ti10Mo or Ti20Nb sample. The influences of Mo and Nb on the passivity of TiMo and TiNb alloys during the ultrasonic cavitation erosion are detected by potentiodynamic curves. The results display that Ti, TC4, TixMo (x = 1, 5, 10) and TixNb (x = 5, 10, 20) samples are all almost in the passive state within the potential region from 0V_SCE to 1.5V_SCE during ultrasonic cavitation erosion, and the passive current density evidently decreases with increasing Mo or Nb content, indicating the enhanced passive characteristic by adding Mo or Nb alloys during the ultrasonic cavitation erosion.     

TC11钛合金光谱分析标准物质的研制

研制了TC11钛合金光谱分析标准物质,采用合理的熔炼和锻造工艺保证了标准物质的均匀性．经方差法和极差法检验,各元素均匀性良好。采用9家权威实验室协作定值,确定的标准值准确可靠,与国内外同类标准物质比对,结果表明,该套标准物质达到了同类标准物质国际先进水平。     

Ti80钛合金光谱分析标准物质的研制

采用海绵钛,Al-Mo,Al-Zr,Al-Nb,Al-Si中间合金等为原材料,通过真空自耗电极电弧炉和真空自耗电极电弧凝壳炉复合熔炼工艺和均匀化变形加工工艺制备了国内首套Ti80(Ti-6Al-3Nb-2Zr-1Mo)钛合金光谱分析标准物质,方差法检验表明各元素均匀性良好。经9家权威实验室协作定值,Al,Nb,Mo,Zr,Fe,Si,C 7种元素的标准值准确可靠,不确定度水平达到了同类样品国际先进水平。该套标准物质各元素成分梯度分布均匀,线性与一致性良好,在不同型号直读光谱仪和X射线荧光光谱仪上的应用效果良好。     

Ti-6Al-4V钛合金光谱分析标准物质的研制

采用真空自耗电极电弧炉与凝壳炉复合熔炼工艺,以及交互式镦拔均匀化变形加工技术,制备了Ti-6Al-4V钛合金光谱分析标准物质。采用方差法和极差法进行均匀性检验,结果表明,Al、V、Fe、Si、C5种元素的均匀性良好。经多家协同定值,确定的标准值准确可靠。经多种光电直读光谱仪应用表明,本套标准物质成线性良好。本套标准物质的均匀性、成线性、标准值及不确定度达到国际同类标准样品的先进水平。