[T9] Innovative Technology

[17E-T9-03] Influencing Factors and Evaluation System of Steam Treatment Layer of Iron-Based Powder Metallurgy Parts

*C. Bao¹, Y. Zhu¹, Z. Chen¹, D. Fang² (1.NBTM New Materials Group Co., Ltd., China, 2.Kunming University of Science and Technology, China)

Keywords:Steam treatment, dynamics process, adhesion forces, indentation tests, scratch tests

Steam treatment (ST) is a widely used strengthening method for iron-based powder metallurgy (PM) products, which can significantly improve the hardness of products in a short time. And a ceramic layer (Fe₃O₄) with excellent corrosion and wear resistance would form on the surface. Herein, the reaction principles, as well as the influence of reaction thermodynamic and kinetic processes on the quality of ST layer are described systematically in this work. In addition, the testing methods and standards for the ST layer are not uniform so far and a series of reliable testing methods are urgently needed. Based on this situation, this work not only systematically lists the feasible methods for thicknesses, structures, compositions and adhesion forces of ST layers, but illustrates the advantages and disadvantages of each method. In general, this work elucidates the thermodynamic and kinetic process of steam treatment reaction, and provides systematic test methods for the thicknesses, structures and adhesion forces of steam treatment layers. This work has a positive role in promoting the standardization of steam treatment technology.