热处理对Cu-14Fe-C合金组织和性能的影响

Effect of heat treatment on microstructure and properties of Cu-14Fe-C alloy

采用真空熔炼制备了Cu-14Fe-C合金，研究了热处理对合金显微组织、力学性能和导电性能的影响规律。结果表明：Cu-14Fe-C合金在950℃固溶处理后部分树枝状相发生溶解、数量减少，大量铁溶入铜基体中，合金硬度和导电率显著降低；进一步时效处理后基体上析出大量细小的含铁相颗粒，弥散强化作用使Cu-14Fe-C合金硬度有所提高；含铁相的析出使基体对电子的散射作用大大减弱，合金导电率显著提高，并且高于铸态合金。随着时效温度从400oC提高到550℃，合金硬度和导电率都不断升高，但接近550℃时升高的趋势显著减缓。

Cu-14Fe-C alloy was prepared by vacuum melting method, and the influence of heat treatment on its microstructure, mechanical proper＇ties and conductivity were studied. The results show that dendritic phase in Cu-14Fe alloy can he spheroidized by carbon, and the hardness along with conductivity are remarkably improved. After heat treatment at 950 ℃, both the hardness and the conductivity of Cu- 14Fe-C alloy decrease significantly due to the fact that the dendritic phase partly dissolves and its quantity decreases, leading to a large amount of iron dissolves into the copper matrix. After further aging treatment, a large number of small iron particles precipitate out and the hardness of Cu-14Fe-C alloy slightly increases for dispersion strengthening. Precipitation of iron-containing phase greatly weakens electron scattering effect of the matrix, resulting in the conductivity increases significantly and exceeds that of cast alloy. As the aging temperature increases from 400 ℃ to 550 ℃, the hardness and conductivity of the alloy increase continuously, but the trend of increasing notably slows down at close to 550 ℃.