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采用扫描电镜、X射线衍射分析等手段 ,研究了正火处理对Cu Al Be B合金组织、相结构及阻尼和力学性能的影响 ,并原位观察拉伸应力作用下裂纹的萌生和扩展过程。研究结果表明 ,Cu Al Be B合金具有较高的阻尼性能 (S D C =17%～ 19% ) ,正火处理可抑制α相的析出 ,并减少γ1′的混杂程度 ,从而进一步提高阻尼能力。各向弹性异性和相变应变差引起的晶界集中应力 ,导致Cu A1 Be B合金在拉伸条件下发生晶间断裂。正火处理不但纯净晶界 ,形成马氏体共格晶界 ,而且减小晶内γ1′马氏体与 β1′马氏体的混合程度 ,有利于减少晶界应力集中和可能萌生的晶界裂纹源 ,从而有效改善合金的塑性和强度。
The effects of normalizing treatment on the microstructure, phase structure, damping and mechanical properties of Cu Al Be B alloy were investigated by means of scanning electron microscopy and X-ray diffraction analysis. The initiation and propagation of cracks under tensile stress were observed in situ. The results show that Cu Al Be B alloy has high damping capacity (S D C = 17% -19%). Normalizing treatment can suppress the precipitation of α phase and reduce the degree of γ1 ’mixing, thus further improving the damping capacity. The stress concentration in the grain boundaries caused by the anisotropy of anisotropy and the strain of phase transformation leads to the intergranular fracture of Cu A1 Be B alloy under the tensile conditions. Normalizing not only the pure grain boundary, the formation of martensite lattice boundaries, but also reduce the intragranular γ1 ’martensite and β1’ martensite mixing degree is conducive to reducing the stress concentration of grain boundaries and possible initiation of grain boundaries Crack source, which effectively improve the plasticity and strength of the alloy.