Co_3Ti金属间化合物的环境氢脆及氢扩散

ENVIRONMEMTAL EMBRITTLEMENT AND HYDROGEN DIFFUSION IN Co_3Ti ALLOYS

研究了硼对Co3Ti环境脆性的影响，证明硼对Co3Ti合金无抑制环境氢脆的作用．用一种新方法测定了Co3Ti中氢的扩散系数，证明加硼或不加硼Co3Ti合金中氢的扩散系数相同，表明硼不降低氢的沿晶扩散，加硼Co3Ti合金仍然对水汽诱发的环境氢脆敏感是由于硼不偏聚在Co3Ti晶界，不能有效抑制氢的沿晶扩散所致．

The effect of boron doping on the sensitivity to environmental embrittlement of Co3Ti alloys was investigated. The results show that the boron doping in Co3Ti does not have the effect on suppressing environmental embrittlement. The hydrogen diffusion coefficients in Co3Ti alloys with and without boron measured by a new experimental method have almost the same value, which indicates that boron in Co3Ti alloys does not reduce the hydrogen diffusivity along the grain boundaries. The susceptibility of boron-doped Co3Ti alloys to moisture-induced environmental embrittlement is attributed to no boron atoms segregating to the grain boundaries.