The solubility of hydrogen in polycrystalline Ni3Al, and in single crystals of Ni3Al doped with B and Ta, had been measured as a function of temperature. The solid phase was in equilibrium with H2 gas at a constant pressure of 1.01 x 105N/m2. These studies showed that the H-solubility (H-atoms per metal atom) increased with increasing temperature, reached a pronounced peak at about 750K, and then decreased rapidly with increasing temperature. The peak temperature was essentially the same for non-doped single crystals, polycrystals and doped single crystals. The present work extended these measurements to include doped polycrystalline material containing both B (0.2at%) and Zr (0.5at%) as dopants.
The Solubility of Hydrogen in Ni3Al Polycrystals Doped with B and Zr. Yang, L., McLellan, R.B.: Scripta Metallurgica et Materialia, 1995, 32[5], 779-80
Figure 13
Diffusivity of H in Ni3Al
White circles, Ni-21.5Al-1at%Zr; black circles, Ni-21.7Al-0.34Zr-0.1at%B
Table 17
Arrhenius parameters for H diffusion in Ni3Al alloys
Composition (at%) | Range (C) | Do(m2/s) | E (kJ/mol) |
Ni-21.7Al-0.34Zr-0.1B | 100-250 | 1.5 x 10-11 | 7.3 |
Ni-21.5Al-1.0Zr | 350-420 | 1.6 x 10-6 | 81.6 |
Ni-21.5Al-1.0Zr | 100-250 | 2.0 x 10-11 | 7.7 |
Ni-21.7Al-0.34Zr-0.1B | 350-420 | 1.6 x 10-6 | 81.6 |