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本文报导了对以Ni3Al为基的r′单晶体所做的蠕变及持久试验的结果。结果表明,r′晶体的稳态蠕变速εs遵从 εs=Cσmexp(-Qc′/RT) 的关系。指数m仅和温度有关。m(850℃)=3.95,m(950℃)=3.62。对Ni3Al,Qc′=88kcal/g-at。合金元素Ti,Nb,W都使Qc′升高,其中Nb的作用最大,然而W在提高蠕变强度上最有效。晶体取向对εs有显著影响。取向的Ni3Al晶体εs最低,持久寿命tr最长。在1050℃,σ=5kg/mm2时,tr可≥100小时,Ni3Al单晶体也同样符合Monkman-Grant关系tr(εs)p=常数,其中p=0.82。r′晶体蠕变中的滑移系统是{111}。In this paper, the results of creep and stress-rupture tests on Ni3Al base γ′ monocrystals are presented. The results show that the steady state creep rate εs conforms to the relationship: εs=Cσmexp(-Qc′/RT). The exponent m depends only on temperature. m(850℃)=3.95, m(950℃) = 3.62. The apparent activation energy of creep Qc′ amounts to 88 k cal/g-at. for Ni3Al crystals. All of the alloying elements studied Ti, Nb and W raise Qc′, the effect of Nb being the greatest, while W proves to be most effective in improving the creep strength. The orientation of crystals has a marked influence on εs. oriented crystals have the lowest εs and the longest stress-rupture life tr. tr≥ 100 hr for T= 1050℃ and σ= 5 kg/mm2. The Monkman-Grant relation tr(εs)p=const. holds likewise for Ni3Al single crystals, with p = 0.82.The glide system of γ′ crystals in creep appears to be {111} .
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