ADVANCEDION–PLASMASURFACEENGINEERINGOFHIGH-SPEEDSTEELCUTTINGTOOLSFORMACHININGDIFFICULT-TO-CUTALLOYS

High-speedsteelcuttingtoolsarestillwidelyusedinmachiningoperationsinvolvingcomplexgeometriesandhighdynamicloads.However,theirapplicationislimitedbyintensivewearandplasticdeformationatelevatedtemperatures.Thisstudyinvestigatesacomplexion–plasmasurfacemodificationapproachcombiningionnitriding,ionalloying,andmultilayernitride-basedcoatingstoimprovethewearresistanceandoperationalstabilityofhigh-speedsteeltools.Ionnitridingwasappliedtoformahardeneddiffusionlayer,followedbyionalloyingusingNb–Hfsystemsandthedepositionofa(TiAl)N-basedcoating.Cuttingtestsperformedduringmachiningofachromium–nickelalloydemonstratedasignificantreductionincuttingforcesanda3–4-foldincreaseintoollifecomparedtoconventionallycoatedtools高速钢切削刀具仍广泛应用于涉及复杂几何形状与高动态载荷的机械加工作业中。然而，这类刀具的应用受限于高温环境下的剧烈磨损与塑性变形。本研究提出一种复合离子等离子体表面改性方案，该方案结合了离子渗氮（ion nitriding）、离子合金化（ion alloying）以及多层氮化物基涂层（multilayer nitride-based coatings）技术，用以提升高速钢刀具的耐磨性与服役稳定性。研究先通过离子渗氮形成硬化扩散层，随后采用铌-铪（Nb-Hf）体系开展离子合金化处理，并沉积(TiAl)N基涂层。针对铬镍合金的机械加工切削试验结果表明，与传统涂层刀具相比，该改性刀具的切削力显著降低，刀具寿命提升3至4倍。