非晶合金宇航服役热环境下蠕变行为研究

Research on Creep Behaviors of Metallic Glass at Space Thermal Environment

通过宏观尺度蠕变实验,在宇航服役环境范围内,对锆基非晶合金蠕变行为进行了研究。结果表明,在200℃时,非晶合金未发生显著的压缩蠕变,其长期变形比率与自由体积的增值数值变化存在表观一致,说明自由体积作为孕育形成剪切带的初始结构单元,在非晶合金蠕变变形中具有重要作用。在300℃时,非晶合金在低于屈服强度和玻璃转变温度的条件下,发生了显著的压缩和拉伸蠕变,实验结果给出了在宇航热环境下非晶合金的可靠服役热环境边界和载荷包络。锆基非晶合金服役温度不超过200℃,载荷不超过1000 MPa。

The creep behaviors of zirconium base(Zr-based)metallic glass proposed serving in the space environment were studied by macro-scale creep test method.The results showed that no significant creep in compression indicated in 200℃,and the long-term deformation ratio indicated the same value to its excess free volume,which indicates that free volume plays an important role in the creep deformation of amorphous alloys as the initial structural unit for the formation of shear bands.In below the yield strength and glass transition temperature of Zr-based the metallic glass,respectively,the compressive and tensile creep behavior significantly changed in 300℃.In this study,the experimental results of Zr-based metallic in creep further define the serving thermal and mechanical limits in space.It′s service temperature should not exceed 200℃and the load can′t exceed 1000 MPa.