A Study of Boronizing Kinetics and Its Effect on the Structure and Mechanical Properties of Steel 16MnCr5


Calik A., UÇAR N., Yeniay N.

METAL SCIENCE AND HEAT TREATMENT, 2022 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Publication Date: 2022
  • Doi Number: 10.1007/s11041-022-00762-5
  • Journal Name: METAL SCIENCE AND HEAT TREATMENT
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, Compendex, Metadex, Civil Engineering Abstracts
  • Keywords: boronizing (boriding), steel 16MnCr5, kinetics, activation energy, mechanical properties, AISI P20 STEEL, GROWTH-KINETICS, BORIDE LAYERS, BEHAVIOR, WEAR

Abstract

The kinetics of boronizing of low-alloy steel 16MnCr5 at 1123, 1173 and 1223 K for 2, 4 and 6 h in powder mixtures using the Ekabor-II agent is studied for determining the possibility of raising the surface properties of this steel. The microstructure is studied using optical and electron microscopy and x-ray diffractometry. The mechanical properties of the steel boronized by different variants are analyzed. It is shown that the growth of the boride layer with time obeys a parabolic dependence. The activation energy of boron diffusion and the pre-exponential factor are determined. An empirical equation is obtained for predicting the thickness of boronized layer on steel 16MnCr5 as a function of the temperature and time of the boronizing. Boronizing is shown to increase the yield strength and the ultimate tensile strength of the steel at lowering of the ductility. Boronizing at 1223 K for 6 h produces a boronized layer with a hardness of 1940 HV0.1 at a hardness of the matrix equal to 401 HV0.1.