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在室温下利用纳米压痕测试技术研究了峰值载荷和加载速率对U65Fe30Al5新型非晶合金蠕变行为的影响规律。结果表明,随着峰值载荷和加载速率的增加,在相同蠕变时间内,蠕变位移呈增大趋势,但当加载速率高于特定阈值时,蠕变位移不再增大。通过蠕变经验公式拟合发现,蠕变过程的应力指数随峰值载荷的增加不断变大,但随加载速率的增加先减小后基本恒定。与常规晶态合金相比,U65Fe30Al5非晶合金具有更大的应力指数,这反映出后者内部结构中富含自由体积。
The effect of peak load and loading rate on the creep behavior of U65Fe30Al5 amorphous alloy was studied by using nanoindentation technique at room temperature. The results show that with the increase of peak load and loading rate, the creep displacement increases with the increase of peak load, but the creep displacement no longer increases when the loading rate is higher than a certain threshold. The empirical formula of creep shows that the stress exponent of creep process increases with the increase of peak load, but decreases first and then decreases with the increase of loading rate. Compared with conventional crystalline alloys, U65Fe30Al5 amorphous alloy has a larger stress index, which reflects the latter’s internal structure rich in free volume.