塑性变形与热处理对Co-Ni-Cr-Mo基合金低阻尼性能的影响

Evaluation of Low-Damping Properties Induced by Plastic Deformation and Heat Treatment in Co-Ni-Cr-Mo-Based Alloy

摘要:

研究了添加0.5wt% Nb的Co-Ni-Cr-Mo基合金在不同塑性变形和热处理条件下的强度和阻尼性能。通过维氏硬度测试、自由共振杨氏模量测量和微观组织分析，阐明了位错密度、空位形成和再结晶对该合金性能的影响。结果表明，随着轧制变形程度的增加，位错密度升高，阻尼性能得到增强，而在再结晶温度以下的时效处理通过Suzuki效应导致的位错钉扎作用降低了阻尼性能。再结晶热处理可恢复材料的原始组织结构和阻尼水平。该合金的抗拉伸强度约为1500 MPa，对数衰减值δ^-1处于2×10^-4~3×10^-4之间，表现出优异的力学性能，相较于Ti基合金更具优势，使其成为超声波工具和医疗应用的理想材料。

Abstract:

The strength and damping properties of Co-Ni-Cr-Mo-based alloys with 0.5wt% Nb addition after various plastic deformation and heat treatment processes were investigated. Through Vickers hardness tests, free resonance Young's modulus measurements, and microstructure analysis, the effects of dislocation density, vacancy formation, and recrystallization on the alloy performance were clarified. Results indicate that increasing the rolling reduction enhances damping property due to higher dislocation density, whereas aging below the recrystallization temperature reduces damping property via dislocation pinning by the Suzuki effect. Recrystallization heat treatment restores the original structure and damping level. This alloy possesses tensile strength of approximately 1500 MPa and logarithmic decrement value δ^-1 in the range of 2×10^-4–3×10^-4, demonstrating superior mechanical properties compared with the Ti-based alloys, which makes it an excellent candidate material for ultrasonic tools and medical applications.