中碳Fe-Cr-C堆焊合金成分设计与热处理工艺优化

为了改善堆焊再制造后中碳Fe-Cr-C合金部件的综合使用性能，采用Thermo-Calc计算软件研究了微合金化元素Ni，Mn和V对堆焊合金相析出的影响，在调控成分的基础上，制备了新型中碳Fe-Cr-C合金药芯焊丝；将所获得的堆焊试样在不同温度、不同保温时间条件下进行回火处理，结合回火试样的显微组织和硬度，确定最优的热处理工艺方案. 结果表明，合金元素Ni和Mn可以扩大堆焊合金的奥氏体相区，改善其韧性，而合金元素V可以促使MC型碳化物析出，提高其硬度及耐磨性；新型堆焊合金在480 ℃保温2 h后不仅具有最高的硬度，而且抗回火性能最强.

Composition design and heat treatment procedure optimization for the medium-C Fe-Cr-C surfacing alloy

In order to improve comprehensive performance of remanufactured components made of medium carbon Fe-Cr-C alloy, the influence of alloying element Ni, Mn and V on the phase composition of the surfacing alloy was researched by Thermo-Calc calculation software, and then the new flux-cored wire was designed and prepared. Subsequently, the obtained surfacing alloy was tempered at different temperature and holding time. The optimal heat treatment procedure was obtained by observing microstructure and measuring hardness. The results showed that elements Ni and Mn could expand the austenite zone of the surfacing alloy and then improve the toughness, while element V could promote the precipitation of MC carbide, and increase the hardness and wear resistance. The surfacing alloy showed the highest hardness and expressed the most excellent tempering resistance after tempering at 480 °C for 2 h.