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采用动态机械分析仪 (DMA) 和场发射扫描电镜 (FESEM) 研究了1.0\%Nb, 1.0%Ti和0.5%Cu (质量分数) 添加对Fe--13Cr--2.5Mo合金阻尼性能和腐蚀性能的影响. 结果表明: 添加Nb的合金中, 形成的大量(Nb, Mo)C相会阻碍磁畴壁的运动, 严重影响合金的阻尼性能;  当应变振幅大于3.5×10^-5时, 析出相 (Nb, Mo)C与位错的交互作用会引起静滞后型位错阻尼Q_dis^-1, 致使在高应变振幅区合金阻尼性能明显提高; 加入Ti或Cu后合金晶界碳化物明显减少, 而晶内析出相明显增多, 导致合金的阻尼性能在低应变振幅区略有降低. 点蚀结果表明, 三种合金元素的添加都能提高合金的耐蚀性能, 其中添加1.0%Ti的合金可同时获得良好阻尼性能和耐蚀性能.

Fe--Cr base high damping alloys (HDA), as the typical ferromagnetic type HDA, have been well investigated in a long history due to their merits in
low cost and superior workability like steels, and are widely applied for suppression of noise or vibration in many industrial fields. The  agnetoelastic
coupling in ferromagnetic materials is well known to be an important source of internal friction, which could produce a high damping capacity. The
damping mechanism has been mainly attributed to the stress--induced irreversible movements of magnetic domain walls. Fe--(12%---16%)Cr--(2%---4%)Mo (mass fraction) base alloys were found to possess higher damping capacity and better corrosion resistance. As well known Nb, Ti and Cu can improve corrosion resistance of stainless steel. In the present work, dynamic mechanical analyzer (DMA) and field--emission scanning electron microscope (FESEM) were used to investigate the influences of additions of 1.0%Nb, 1.0%Ti and 0.5%Cu on the damping capacity and corrosion resistance of Fe--13Cr--2.5Mo alloy. The results show that addition of 1.0%Nb causes abundant precipitations of (Nb, Mo)C, which
can obstruct the movement of domain walls, and significantly deteriorate the damping capacity at low strain amplitude. At strain amplitudes higher than 3.5×10^-5, the amplitude--dependent dislocation damping Q_dis^-1 is generated due to dislocations interaction with (Nb, Mo)C, so the damping
capacity of Nb--containing alloy becomes higher than other alloys. Addition of Ti or Cu inhibits the precipitation of grain--boundary carbides,
while promotes the intragranular precipitations in the alloy distinctly. As a result, the damping capacity of the alloy with Ti or Cu is slightly lower than that of Fe--13Cr--2.5Mo alloy. Pitting corrosion test indicates that the  three alloying elements can all improve the corrosion resistance of Fe--13Cr--2.5Mo damping alloy. The 1.0%Ti--containing alloy possesses not only high damping capacity but also good corrosion resistance.