Microstructure and properties of vacuum chromized layer on PCrNi3Mo steel

doi:10.13251/j.issn.0254-6051.2022.08.028

Abstract

Abstract: Vacuum chromizing on the surface of PCrNi3Mo steel was performed. The microstructure and properties of the chromized layer were analyzed by means of X-ray diffraction(XRD), scanning electron microscope(SEM), optical microscope, microhardness test, dry sliding friction and electrochemical corrosion test. The results show that the surface of the PCrNi3Mo steel after vacuum chromizing forms a chemical compound coating of Cr₂₃C₆, Cr₇C₃ and (Cr, Fe)₇C₃, and the chromized layer is dense and well bonded with the substrate. The depth, surface microhardness, wear resistance and electrochemical corrosion resistance of the chromized layer increase with the increase of chromizing time. When chromized for 12 h, the PCrNi3Mo steel has the best comprehensive properties, of which the thickness of chromized layer is about 11 μm, the surface hardness is 1117.1 HV0.5, the friction coefficient is the lowest, the wear mass loss is 0.1225 mg and the self-corrosion current density is 2 orders of magnitude lower than that of the substrate.

Key words: PCrNi3Mo steel, vacuum chromizing, microstructure, properties

CLC Number:

TG174.445

Feng Lingxiao, Jin Hao, Yang Li. Microstructure and properties of vacuum chromized layer on PCrNi3Mo steel[J]. Heat Treatment of Metals, 2022, 47(8): 168-172.

References

[1]张楠, 吕超然, 徐乐. 火炮身管用钢现状及发展趋势[J]. 中国冶金, 2019, 29(5): 6-9.
Zhang Nan, Lü Chaoran, Xu Le. Current status and development trend of gun barrel steel[J]. China Metallurgy, 2019, 29(5): 6-9.
[2]郭峰, 黄进峰, 吴护林. 高强韧炮钢的组织和力学性能[J]. 金属热处理, 2005, 30(11): 31-34.
Guo Feng, Huang Jinfeng, Wu Hulin. Microstructure and mechanical properties of a gun steel with high strength and toughness[J]. Heat Treatment of Metals, 2005, 30(11): 31-34.
[3]焦贵伟, 胡朝根. 火炮身管寿命评估预测[J]. 兵工学报, 2018, 39(5): 66-69, 74.
Jiao Guiwei, Hu Chaogen. Research of evaluation and prediction technology for gun barrel life[J]. Journal of Ordnance Equipment Engineering, 2018, 39(5): 66-69, 74.
[4]Xu K, Wang X F, Cui H C, et al. Investigation on lcf behavior of welded joint at different temperatures for bainite steel[J]. Chinese Journal of Mechanical Engineering, 2019, 32(2): 73-80.
[5]Burton L, Carter R, Champagne R, et al. Army targets age old problems with new gun barrel materials[J]. Amptiac Quartely, 2004, 18(4): 49-55.
[6]赵隆. 某炮钢材料的强化机理研究[D]. 南京: 南京理工大学, 2007.
Zhao Long. A study on the strengthen reason of certain big gun tube material[D]. Nanjing: Nanjing University of Science and Technology, 2007.
[7]李秉旗, 李中麟. 大口径炮弹包装现状与发展趋势[J]. 包装工程, 2009(9): 48-49.
Li Bingqi, Li Zhonglin. Present situation and development trend of large-calibre projectile packaging[J]. Packaging Engineering, 2009(9): 48-49.
[8]Huang C P, Lin X, Yang H O, et al. Microstructure and tribological properties of laser forming repaired 34CrNiMo6 steel[J]. Materials, 2018, 11(9): 28-34.
[9]徐东升, 贾长治, 刘广生, 等. 火炮身管寿命预测技术发展研究[J]. 价值工程, 2013, 37(5): 316-318.
Xu Dongsheng, Jia Changzhi, Liu Guangsheng, et al. The research of gun barrel life expectancy technology development[J]. Value Engineering, 2013, 37(5): 316-318.
[10]许耀峰, 单春来, 刘朋科, 等. 火炮身管寿终机理及寿命预测方法研究综述[J]. 火炮发射与控制学报, 2020, 41(3): 89-94, 101.
Xu Yaofeng, Shan Chunlai, Liu Pengke, et al. Review of the research on failure mechanism and life prediction method of gun barrel[J]. Journal of Gun Launch and Control, 2020, 41(3): 89-94, 101.
[11]周重光, 杨明江, 彭林华, 等. 先进高重频激光处理对镀铬层结合特性的影响[J]. 兵器材料科学与工程, 2003(5): 15-18.
Zhou Chongguang, Yang Mingjiang, Peng Linhua, et al. Effect of advanced high-frequency laser treating on joining condition of chrome cladding materia[J]. Ordnance Material Science and Engineering, 2003(5): 15-18.
[12]Li W Z, Chen Q Z, Polcar T, et al. Influence of Zr alloying on the mechanical properties, thermal stability and oxidation resistance of Cr-Al-N coatings[J]. Applied Surface Science, 2014, 317: 269-277.
[13]Meng J S, Ji Z S. Effect of different fillers on oxidation behavior of low-temperature chromizing coating[J]. Transactions of Nonferrous Metals Society of China, 2014, 24(6): 1785-1790.
[14]Zhou Y B, Chen H, Zhang H, et al. Preparation and oxidation of an Y₂O₃-dispersed chromizing coating by pack cementation at 800 ℃[J]. Vacuum, 2008, 82(8): 748-753.
[15]马朝平, 胡建军, 刘妤. 材料表面渗金属技术的研究进展[J]. 重庆理工大学学报(自然科学), 2016, 30(10): 65-70.
Ma Chaoping, Hu Jianjun, Liu Yu. Research progress of metallic cementation technology on material surface[J]. Journal of Chongqing University of Technology(Natural Science), 2016, 30(10): 65-70.
[16]Hu J J, Zhang Y Q, Yang X, et al. Effect of pack-chromizing temperature on microstructure and performance of AISI 5140 steel with Cr-coatings[J]. Surface and Coatings Technology, 2018, 344: 656-663.
[17]Wu C L, Hong Y, Chen W L, et al. A double strengthened surface layer fabricated by nitro-chromizing on carbon steel[J]. Surface and Coatings Technology, 2016, 298: 83-92.
[18]Hu J J, Ma C P, Yang X, et al. Microstructure evolution during continuous cooling in AISI 5140 steel processed by induction heating chromizing[J]. Journal of Materials Engineering and Performance, 2017, 26(11): 5530-5537.
[19]Zeng J, Hu J J, Yang X, et al. Evolution of the microstructure and properties of pre-boronized coatings during pack-cementation chromizing[J]. Coating, 2020, 10(2): 159-172.
[20]王洪孔, 郑可, 高洁, 等. γ-TiAl 合金表面 TiC渗镀层的摩擦磨损性能[J]. 中国表面工程, 2018, 31(6): 28-34.
Wang Hongkong, Zheng Ke, Gao Jie, et al. Wear properties of TiC permeation layer prepared on γ-TiAl alloy[J]. China Surface Engineering, 2018, 31(6): 28-34.
[21]李龙博, 李争显, 刘林涛, 等. 反应温度及时间对奥氏体不锈钢渗铬层组织结构的影响[J]. 稀有金属材料与工程, 2021, 50(5): 1743-1752.
Li Longbo, Li Zhengxian, Liu Lintao, et al. Effect of reaction temperature and time on microstructure of chromizing layer on austenitic stainless steel matrix[J]. Rare Metal Materials and Engineering, 2021, 50(5): 1743-1752.