Shen Qianqian, Zhang Yu, Li Xuesha, Xiang Li, Nie Chaoyin
School of Materials and Energy, Southwest University, Chongqing 400715, China.
Nanomaterials (Basel). 2020 Dec 24;11(1):31. doi: 10.3390/nano11010031.
In order not to sacrifice nitrided layer thickness and reduce brittle compound layer thickness, Ni-coated pretreatment was carried out with electrodeposition on a pure iron surface, followed by gas nitriding. The brittle compound layer thickness of duplex surface treated samples was reduced, and the nitrided layer thickness increased to 320 μm. The microhardness was 4 times harder, and the wear loss was reduced by 68% compared with the original material. The results indicate that Ni-coated pretreatment could effectively improve microhardness and wear resistance and realize the controlled microstructure of a brittle compound layer of pure iron without compromising nitrided layer thickness. Ni coating plays an important role in ammonia adsorption and decomposition, and in the transfer of active nitrogen atoms during nitriding.
为了不牺牲渗氮层厚度并减小脆性化合物层厚度，在纯铁表面进行了电沉积镀镍预处理，随后进行气体渗氮。经双相表面处理的样品的脆性化合物层厚度减小，渗氮层厚度增加到320μm。显微硬度提高了4倍，磨损损失与原始材料相比降低了68%。结果表明，镀镍预处理可以有效提高显微硬度和耐磨性，并在不影响渗氮层厚度的情况下实现对纯铁脆性化合物层微观结构的控制。镍涂层在氨的吸附和分解以及渗氮过程中活性氮原子的转移中起着重要作用。
