Ni和Nb元素对Fe-Cr-Mo合金力学和阻尼性能的影响

摘要：采用光学显微镜、扫描电镜、透射电镜、弯曲共振试验机和万能材料试验机等分析了复合添加质量分数0.8%Ni元素和0.1%Nb元素的Fe-Cr-Mo合金组织和析出相的大小、形态，研究了Ni和Nb元素的添加对Fe-Cr-Mo合金力学性能和阻尼性能的影响。结果表明，Ni和Nb元素的加入不但使合金晶粒显著细化，而且有效抑制了富Cr析出物的析出，使析出物明显细化且分布弥散。晶粒和析出物的细化同时提高了合金的强度和塑韧性，尤其是显著地提高了材料的塑性。1000和1100℃退火后，Ni和Nb元素的加入将提高减振合金的矫顽力，降低磁致伸缩系数，使减振合金的阻尼性能降低。900℃退火后，Ni和Nb元素的添加虽然提高了合金的矫顽力，但由于Mo元素的回溶使磁致伸缩系数增大，阻尼性能获得提高。

Effect of Ni and Nb on mechanical properties and damping capacity of Fe-Cr-Mo alloy

The microstructure and the size and morphology of precipitates of Fe-Cr-Mo alloy with 0.8%Ni and 0.1%Nb addition were analyzed by optical microscope, scanning electron microscope and transmission electron microscope. The influences of Ni and Nb on the mechanical properties and damping capacity of Fe-Cr-Mo alloy were studied by bending resonance device and universal material testing machine. The results indicated that the addition of Ni and Nb not only resulted in significant refinement of grain size, but also effectively inhibited the precipitation of Cr rich precipitates, and caused dramatically refinement and dispersion of precipitates. The refinement of grains and precipitates simultaneously increases the strength and plasticity of experimental alloys, especially the significant enhancement in plasticity. After annealing at 1000 and 1100℃, the addition of Ni and Nb increased the coercivity and decreased the magnetostrictive coefficient of the damping alloy, and thus reduced the damping capacity. After annealing at 900℃, although the Ni and Nb addition enhanced the coercive force of Fe-Cr-Mo alloy, the re dissolution of Mo increased the magnetostrictive coefficient, and thus the damping capacity was improved.