@article{oai:iwate-u.repo.nii.ac.jp:00009937,
 author = {清水, 友治 and 岩渕, 明 and 吉野, 泰弘 and 片桐, 一宗 and 新田, 勇},
 issue = {586},
 journal = {日本機械学會論文集. A編},
 month = {Jan},
 note = {In order to consider the tribological properties of magnet-structural materials at cryogenic temperatures, the authors require the hardness value of the materials at cryogenic temperatures. Therefore, a low-temperature Vickers-type hardness tester has been developed. The hardness tester consists of the driving device of the indenter, load control system, specimen transfer device and cooling system. The measured hardiness for eight materials were equivalent to those obtained by a conventional Vickers micro-hardness tester at room temperature which means that the developed hardness tester has sufficient performance as hardness tester. The temperature dependence of the hardness was obtained between 77 K and 293 K for stainless steels of JN1, JN2 and SUS316L, Ti-alloy and Copper. It was found that the hardness increased with decreasing temperature, where the hardness at 77 K is three times the hardness at 293 K for stainless steels, and is twice for copper. The relationships between the increase of hardness and the reciprocal of temperature were expressed in Arrhenius equations. The relationships between hardness and yield stress or tensile strength were examined. The hardness is more than three times greater than yield stress or tensile strength.},
 pages = {1431--1437},
 title = {極低温硬さ計の開発},
 volume = {61},
 year = {1995}
}