Ti_(50)Ni_(16)Cu_(25)Nb_9阻尼合金的研制

Ti_(50)Ni_(16)Cu_(25)Nb_9 Internal Friction Alloy

Ti50Ni16Cu25Nb9是在TiNiCu阻尼合金的基础上发展的一种新型阻尼合金。X射线衍射(XRD)和能谱(EDS)分析表明,Nb的加入使Ti50Ni16Cu25Nb9合金在凝固过程中发生共晶反应,生成单斜结构的B19′马氏体和fcc结构β-Nb相。晶粒内部为富Ni贫Cu马氏体与β-Nb相的共晶组织,晶间为富Cu贫Ni相,合金中存在明显的微观偏析。高温固溶热处理可以改善合金的微观偏析,但是随着热处理温度的增加,β-Nb软化相有球化趋势,相含量减少,不利于优化合金的阻尼性能。900℃×2 h+WQ热处理可以明显改善合金的微观偏析,并保留适量的条状β-Nb相。

Ti50Ni16Cu25Nb9 is one kind of new internal friction alloys, which is developed on the TiNiCu alloys. X-Ray Diffraction （XRD） and Energy Dispersive Spectrometer （EDS） analysis indicated that eutectic reaction occurred during the solidification process, in which the B19′ martensite and γ - Nb were produced. Ni element was enriched in the center of crystal grain, and Cu dement was enriched in grain boundary, which illustrate that there is obvious microsegregation in Ti50Ni16Cu25Nb9 alloy. So the solution heat-treatment is necessary to improve the microsegregation of the alloy at high temperature. Yet the increasing of solution temperature may result in the decrease of β - Nb, which is negative to the ability of Ti50Ni16Cu25Nb9 internal friction. 900 ℃ × 2 h ＋ WQ solution heat-treatment can obviously improve the microsegregation of the alloy, and withhold enough β - Nb phase.