Structural and Microstructural Function of Protium

氕的结构和微观结构功能

基本信息

批准号：
10148101
负责人：
AOKI Kiyoshi
金额：
$ 81.28万
依托单位：
Kitami Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas (A)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2001
项目状态：
已结题

项目摘要

The pressure dependence of structural changes of C15 Laves phase TbFe_2 heated in a hydrogen atmosphere was investigated using PDSC, XRD, DSC and a hydrogen analyzer. Hydrogen absorption in the crystalline state, hydrogen-induced amorphization (HIA), precipitation of TbH_2 and decomposition of the remaining amorphous alloy into ヲチ-Fe and TbH_2 occurred exothermally with increasing temperature above 0.5 MPa H_2, independent of the heating rate. HIA and precipitation of TbH_2 occurred simultaneously in 0.2 MPa H_2 (O.33 K/s) and in 0.1 MPa H_2 (0.17 K/s). On the contrary, hydrogen absorbed crystalline c-TbFe_2H_<3.5> decomposed directly into ヲチ-Fe and TbH_2 in O.1 MPa H_2 (O.33 K/s). That is, no amorphous phase was formed at the lower hydrogen pressure and at a high heating rate. The reason why HIA occurs above the critical hydrogen pressure and below the critical heating rate was discussed on the basis of the hydrogen content absorbed in the crystalline state of The Fe _2. 2) Formation … More of hydrogen-induced superabundant vacancies has been studied in Cr-H, Mn-H, Ni-H and Nb-H alloys and its energetics and structure dependence has been elucidated. 3) The relationship between hydrogen pressure and temperature (P-Tcurve) in the HDDR treatment of the Sm_2Fe_<l7> compound was investigated. The P-T curve suggested that the HDDR condition of the Sm_2Fe_<l7> compound was more sensitive to temperature than that of the Nd_2Fe_<l4>B compound. In addition, for clarifying the mechanism of anisotropic inducement during the HDDR process in the Nd-Fe-B compound, the crystal orientation relationship between the parent Nd_2Fe_<l4>B phase and the disproportionated mixture was investigated. It can be concluded that retaining the crystallographic orientation relationship such as <111>ヲチ-Fe and <111>NdH_2// <001>Nd_2Fe_<l4>B, (110)ヲチ-Fe and (110)NdH_2//(lOO)Nd_2Fe_<l4>B during HDDR treatment is important for the inducement of anisotropy. 4) It has been found that the tensile specimen of ultra-fine grained Ti-6Al-4V alloy elongates until the diameter of the tip of the broken specimen narrowed to the size of a single crystal. The implant (dental part) was produced using the ultra-fine grained material without crack on the surface by the superplastic forming process. These materials may be applicable as biomaterials in medical industries. Less

利用PDSC、XRD、DSC和氢分析仪研究了在氢气氛中加热的C15 Laves相TbFe_2的结构变化的压力依赖性。剩余的非晶态合金变成Wochi-Fe和TbH_2，随着温度升高到0.5 MPa H_2以上，发生放热，与加热无关在0.2 MPa H_2 (O.33 K/s)和0.1 MPa H_2 (0.17 K/s)下,HIA和TbH_2析出同时发生,而吸氢结晶c-TbFe_2H_<3.5>则直接分解为wochi。 -Fe和TbH_2在O.1 MPa H_2(O.33 K/s)中即无。基于Fe _2 晶态吸收的氢含量，讨论了在较低氢压和高加热速率下形成非晶相的原因。 2) 研究了 Cr-H、Mn-H、Ni-H 和 Nb-H 合金中氢致过剩空位的形成，并阐明了其能量学和结构依赖性。 3)研究了Sm_2Fe_<l7>化合物的HDDR处理过程中氢气压力与温度的关系（P-T曲线），P-T曲线表明Sm_2Fe_<l7>化合物的HDDR条件对温度比Nd_2Fe_更敏感。 <l4>B化合物此外，为了阐明Nd-Fe-B化合物中HDDR过程中各向异性诱导的机制，母体之间的晶体取向关系。研究了Nd_2Fe_<l4>B相和不成比例的混合物，可以得出结论，保留了<111>wochi-Fe和<111>NdH_2//<001>Nd_2Fe_<l4>B等晶体取向关系，(110)。 Wochi-Fe和(110)NdH_2//(lOO)Nd_2Fe_<l4>B期间HDDR处理对于诱导各向异性很重要4)已经发现超细晶Ti-6Al-4V合金的拉伸试样会伸长，直到断裂试样尖端的直径缩小到单晶的尺寸。植入物（牙科部件）是通过超塑性成型工艺使用表面无裂纹的超细颗粒材料制成的，这些材料可用作医疗行业的生物材料。