Journal of Laser Applications, Год журнала: 2025, Номер 37(2)

Опубликована: Апрель 7, 2025

The demanding service environment of feed screws in injection molding machines, characterized by metal friction, extrusion, and polymer corrosion, necessitates enhanced hardness, wear resistance, corrosion resistance. Traditional strengthening methods involve nickel-based coating followed nitriding, yet iron-based coatings, which are more cost-effective. This study compares laser-clad alloy coatings with those postgas utilizing various characterization techniques to assess changes microhardness, metallography, phase composition, elemental distribution. nitriding process significantly alters the microstructure microhardness forming a distinct nitride layer transition layer. Nitrogen ions penetrate surface, γ′-Fe4N ɛ-Fe2-3N phases upon saturation, resulting 200 μm-thick 5 μm compound at surface diffusion primarily α-Fe(N). γ′ achieves maximum 1214.1 HV near decreases depth nitrogen content reduction. At 180 depth, reverts prenitriding levels 850 HV. Below layer, absence leads ferrite decomposition further reduction an average drop from 811.4 480.9 Furthermore, disproportionate ratio within ɛ/γ′ dual-phase system results marked deterioration resistance nitrided specimens. imbalance induces microstructural incompatibilities, compromising both tribological performance electrochemical stability under operational conditions.

Язык: Английский