Microstructural and Tribological Analysis of Boronizing Methods on SAE 52100

摘要

SAE 52100 high-carbon, chromium-containing low-alloy steel typically finds applications in bearings and rotary machine components. In this study, pack, paste and molten salt bath boronizing techniques were compared at constant 5 h soaking period. The boronizing process on SAE 52100 was studied by characterizing the microstructure through an optical microscope and SEM imaging. Surface hardness, diffusion depth and boronized phases were observed on the boronized samples. Dry sand abrasion tester based on ASTM G65 was used to analyse the abrasive wear resistance of the steel samples under ambient condition. The process of boronizing had produced a hard, wear-resistant case with an average hardness of 1400 HV. A relatively uniform case thickness was achieved in salt bath boronizing method, while the slurry paste boronizing method produced the largest diffusion layer thickness.