热循环对82.2Mn-15.8Cu-2Al热敏阻尼材料的内耗性能影响研究

Study on the effect of thermal cycling on the properties of Mn82.2-Cu15.8-2Al thermally sensitive damping material

摘要:

利用内耗方法结合DSC、SEM、 XRD研究了82.2Mn-15.8Cu-2Al(at.%)合金随着经历的热循环增加内耗峰、DSC吸、放热峰均向高温方向移动的变化规律。结果表明：该变化规律是由于合金发生Spinodal分解,形成富Mn区和富Cu区。结合微观组织的作用机制对内耗峰进行分析,计算出了合金低温侧弛豫内耗峰激活能及弛豫时间指前因子分别为:E_a=0.66 eV(升温)、E_a=0.74 eV(降温)；t₀=1.4×10_-15s(升温)、t₀=3.2×10_-18s(降温)。采用峰分离方法,分离出相互耦合的马氏体和反铁磁转变引起的内耗峰,根据分峰拟合结果合理的解释试验现象。

Abstract:

_{:The change rule of friction and thermal properties of the alloy after thermal cycling was study by internal friction method combined with DSC, SEM and XRD. The change rule is that the alloy’s internal friction and DSC peak shift to high temperature when experiencing an increasing number of thermal cycles.The results show that this variation is attributed to the occurrence of Spinodal decomposition of the alloy, which formed Mn rich and Cu rich areas.We combine the mechanism of microstructure analyzed the internal friction peak .We calculated the activation energy(Ea) and the pre-exponential factor of relaxation (t0) of the low temperature side internal friction peak. Ea=0.66 eV(heating), Ea=0.74 eV(cooling),t0=1.4×10-15s(heating),t0=3.2×10-18s(cooling). Using the peak separation method to isolate the internal friction peak,which is caused bySmutual coupling of martensitic transformation and antiferromagnetic transition. According to the fitting results, the experimental phenomena can be explained reasonably.}