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研究了 4种含量的氢对Ti 2Al 2 5Zr钛合金疲劳性能的影响。结果表明 ,自然含氢量的材料具有最好的疲劳性能。而当疲劳载荷大于材料的屈服强度时 ,氢含量对疲劳寿命基本没有影响 ;低于屈服强度后 ,疲劳寿命随着氢含量的升高而下降。认为固溶的原子氢导致驻留滑移带软化 ,裂纹萌生提前 ,造成在较大△σ时充氢试样的疲劳寿命降低 ;而材料中氢化物对驻留滑移带 (PSB)的阻碍作用导致氢化物与基体分离而成为裂纹源 ,是小△σ下疲劳寿命降低的主要原因。
The effects of four hydrogen contents on the fatigue properties of Ti 2Al 2 5Zr titanium alloy were studied. The results show that the natural hydrogen content of the material has the best fatigue properties. When the fatigue load is greater than the yield strength of the material, the hydrogen content has no effect on the fatigue life. When the fatigue strength is lower than the yield strength, the fatigue life decreases as the hydrogen content increases. The results show that the fatigue life of hydrogen-filled samples decreases with larger Δσ, while the hydride in the material hinders the PSB The action causes the hydride to separate from the matrix and becomes the source of the crack, which is the main reason for the decrease of the fatigue life under the small Δσ.