反应堆控制棒材料Ag-In-Cd合金的压缩蠕变行为

COMPRESSIVE CREEP BEHAVIOR OF REACTOR CONTROL ROD MATERIAL Ag-In-Cd ALLOY

研究了铸态Ag-In Cd合金在300—400℃及12—24 MPa压应力范围内的压缩蠕变行为,根据实验结果计算了表观应力指数n和表观激活能Q_a,探讨了合金的压缩蠕变机制.结果表明,随温度和应力的升高,合金的稳态蠕变速率增加,稳态蠕变速率与应力之间呈指数关系.温度为300,350和400℃时,合金的n分别为2.90,4.09和5.77;压应力为12,18和24 MPa时,合金的Q_a值分别为68.1,103.7和131.6 kJ/mol.位错运动形成大量层错是Ag-In-Cd合金在温度为300—400℃,压应力为12—24 MPa下的压缩蠕变控制机制.

Ag-In Cd alloy is widely used as the control rod material in the pressure water reactor （PWR）, so it is very important to research the compressive creep behavior for understanding the mechanical property of control rod materials in pile. The compressive creep behavior of as-cast Ag-In-Cd alloy was investigated using a special apparatus at 300-400℃ and under compressive stresses in the range of 12--24 MPa in this work. The stress exponent n and apparent activation energy Qa of the creep process have been calculated behavior have been discussed. The results show that as well as the mechanisms of compressive creep the compressive creep of the alloy increases with the increase of temperature and compressive stress. The relationship between steady creep rate and stress can be expressed in a power law form. The stress exponent n are 2.90, 4.09 and 5.77 at 300, 350 and 400 ℃ respectively. The apparent activation energy Q~ of the creep process are 68.1, 103.7 and 131.6 kJ/mol under compressive stresses of 12, 18 and 24 MPa respectively. Stacking fault is the primary rate controlling mechanism for the Ag-In-Cd alloy at 300 400 ℃ and the compressive stress range of 12--24 MPa, which was deduced from TEM observation.