Duplex Treatment of Tools and Components: Previous or Subsequent Electron Beam Hardening of Thermochemically-Treated and PVD Hard-Coated Steels for Tools and Components

Abstract

The tribological properties of tools and components are improved by wear resistant coatings deposited by thermochemical processing (nitriding, nitrocarburizing) or physical vapor deposition (PVD) technologies. The properties gradient between the very hard and brittle layer and the soft, ductile, but hardenable matrix material can be significantly improved by previous or subsequent electron beam hardening (EBH). The hardness of matrix material is increased by martensitic transformation up to a certain depth, which results in better load support for the hard coating layer. The influence of the tempering stability of the steels investigated and the chemical and structural stability of the coatings on the chosen sequence of treatments is discussed.

Keywords:

• Combined heat treatment
• Duplex treatment
• EBH
• Electron beam
• Hard coating
• Load support
• Nitriding
• Nitrocarburizing
• Physical vapor deposition
• Surface hardening
• Thermochemical treatment
• TiAlN
• TiCN
• TiN
• Wear resistance