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利用CMT4104电子万能试验机研究了置氢TC21合金在不同温度和应变速率下的超塑性。结果表明,随氢含量增加,TC21合金的流动应力先降低后升高,存在一个最佳变形量。置氢后大部分条件下伸长率随氢含量的增加而降低,但氢含量为0.1wt%时,在880℃,1×10-3s-1条件下变形,获得了1010%的最大伸长率。TEM观察发现,当氢含量较低时,TC21-xH合金主要的超塑变形机制为位错攀移和滑移协调的相界/晶界滑移;当氢含量较高时,由于氢降低了TC21合金的相变点,变形在单相β相区进行,变形机制为由扩散促进位错恢复和攀移的晶界滑动机制。
The superplasticity of TC21 alloy hydrogen set at different temperature and strain rate was studied by using CMT4104 electronic universal testing machine. The results show that with the increase of hydrogen content, the flow stress of TC21 alloy first decreases and then increases, and there exists an optimum deformation amount. After hydrogen set, the elongation decreased with the increase of hydrogen content. However, when the hydrogen content was 0.1wt%, the elongation was reduced under the condition of 880 ℃ and 1 × 10-3s-1, and the maximum elongation of 1010% rate. TEM observation shows that the main superplastic deformation mechanism of TC21-xH alloy is dislocation climbing and slip coordination phase boundary / grain boundary slip when the content of hydrogen is low; when the content of hydrogen is high, hydrogen decreases TC21 alloy transformation point, the deformation in the single-phase β-phase region, the deformation mechanism for diffusion-dislocation recovery and climbing the grain boundary sliding mechanism.