Microstructural, mechanical, and corrosion characterization of nitrogen-implanted plastic injection mould steel


ORTURK O., Onmus O. , WILLIAMSON D. L.

SURFACE & COATINGS TECHNOLOGY, vol.196, pp.333-340, 2005 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 196
  • Publication Date: 2005
  • Doi Number: 10.1016/j.surfcoat.2004.08.163
  • Title of Journal : SURFACE & COATINGS TECHNOLOGY
  • Page Numbers: pp.333-340

Abstract

Nitrogen-ion implantation can be used to improve the wear and corrosion behaviour of moulds for plastic injection by modifying the near-surface layers of these materials. In this study, an FeCr ferritic stainless steel (X36CrMo17, similar to AISI-420F) was ion implanted with 85 keV nitrogen ions to low and high doses of 2x10(17) and 1X10(18) ions/cm(2) at a substrate temperature < 200 degrees C in an industrial implantation facility. The N-implanted layer microstructures, thicknesses, and hardnesses were studied by a combination of symmetric and grazing incidence X-ray diffraction (XRD and GIXRD), conversion electron Mossbauer spectroscopy (CEMS), cross-sectional scanning electron microscopy (SEM), and nanohardness measurements. The friction, wear, and corrosion behaviour were investigated by a pin-on-disc tribo tester and a salt spray corrosion analysis method. The XRD, CEMS, and SEM analyses indicate that the N-implanted layers are similar to 0.05-0.08 mu m thick and are composed of epsilon-(Fe,CrMn)(2+x)N with paramagnetic and magnetic characteristics. The treated layer shows nearly two times better corrosion resistance than does the substrate. The wear and nanohardness measurements indicate that the wear behaviour and the N-implanted layer hardness are dose dependent and the latter is increased by more than a factor of 1.6 for the high-dose implanted specimen in comparison with that of the substrate material. (c) 2004 Elsevier B.V. All rights reserved.