Metal surface modification by plasma boronizing in a two-temperature-stage process

• Published in: Surface & coatings technology Vol. 197; no. 1; pp. 51 - 55
• Main Authors: Nam, Kee-Seok, Lee, Ku-Hyun, Lee, Deuk Yong, Song, Yo-Seung
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.07.2005; Elsevier
• Subjects: Applied sciences; Boron trichloride; Exact sciences and technology; Heat treatment; Metals. Metallurgy; Plasma boronizing; Pores; Production techniques; Surface treatment; Thermochemical treatment and diffusion treatment; Two-temperature-stage process; Pores; Boron trichloride; Two-temperature-stage process; Plasma boronizing; Thermochemical treatment; Plasma; Boriding; Surface treatment
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2004.10.099

A two-step plasma-assisted boronizing process was performed on the AISI 1045 steel substrate to reduce the pore density introduced by a single plasma boronizing process and examine the feasibility of the process. The specimens were plasma boronized for 1 h at 650 °C and subsequently for 7 h at 800 °C. Boronizing was conducted at a pressure of 266 Pa in an atmosphere of 1.5 vol.% BCl 3 (low concentration), 50 vol.% H 2 and balance Ar to minimize the effect of chlorine containing compounds, such as BCl 3, HCl, FeCl 2 and FeCl 3, on formation and growth of the boride layer. It was found that the morphology of the boride layer prepared by the two-step boronizing process was changed from a columnar to a tooth-like structure and the pores in the borided steel were eliminated completely in comparison to those synthesized by the conventional single boronizing process (25%).