ニオブの水素環境脆化に及ぼす温度の影響
2001 年 65 巻 9 号 p. 783-786
詳細
2001 年 65 巻 9 号 p. 783-786
Tensile properties of Nb were investigated in 1.1 MPa hydrogen and argon in the temperature range of 473∼1273 K. The effect of temperature on hydrogen environment embrittlement (HEE) of the material was also examined. The results obtained are as follows:
HEE occurred at the temperature range of 673∼1073 K and showed maximum at 800 K. In this temperature range, hydrogen decreased elongation and ultimate tensile strength of the material with decreasing the strain rate. Cleavage fracture together with the striations was observed on the fracture surface in hydrogen, while ductile rupture was observed in argon. No hydride was observed in the specimen fractured in hydrogen by X-ray diffraction. It is discussed that HEE of Nb occurred at this temperature range by the similar mechanism of HEE of iron without hydride near room temperature.
