THERMOCHEMICAL TREATMENT AND COATINGS

The structure, cohesion and tribological properties of steel ASTM A572 (the Russian counterpart is St6sp) are studied after pack boronizing in a powder mixture at 1123 – 1173 K for 2 – 8 h. The microstructure of the boride layers is studied with the use of optical and scanning electron microscopes. The cohesion of the diboride layers to the substrate from steel ASTM A572 is assessed. The friction coefficient and the wear resistance of the steel are determined by testing by the pin-on-disk scheme. The boronized surface layers are shown to consist of iron borides and to have a tooth morphology and a thickness of 37.40 (cid:2) 6.5 – 238 (cid:2) 36.4 (cid:3) m. The kinetics of the boronizing process is studied by an approach based on determination of the mean diffusivity of boron in Fe2B using the activation energy for a constant incubation period. The results of the calculation are checked experimentally for two additional boronizing conditions at 1123 and 1273 K for 10 h.

[1]  I. Campos-Silva,et al.  Pulsed-DC powder-pack boriding: Growth kinetics of boride layers on an AISI 316 L stainless steel and Inconel 718 superalloy , 2021 .

[2]  Yusuf Kayalı,et al.  Investigation of Wear Behavior and Diffusion Kinetic Values of Boronized Hardox-450 Steel , 2021, Protection of Metals and Physical Chemistry of Surfaces.

[3]  İlyas Türkmen,et al.  Characterization and Kinetic Analysis of Iron Boride Layer Formed on the GGG 70 Ductile Cast Iron , 2021, Transactions of the Indian Institute of Metals.

[4]  M. Keddam,et al.  Kinetic Analysis of Pack-Borided Gray Cast Iron , 2021 .

[5]  Lu Shiqiang,et al.  Growth kinetics of the FeB/Fe2B boride layer on the surface of 4Cr5MoSiV1 steel: experiments and modelling , 2021 .

[6]  M. Keddam,et al.  Mean Diffusion Coefficient Method in Studying Armco Iron Boriding Kinetics , 2020, Metal Science and Heat Treatment.

[7]  M. Keddam,et al.  Simulation of Boriding Kinetics of AISI D2 Steel using Two Different Approaches , 2020, Metal Science and Heat Treatment.

[8]  M. Kulka.  Trends in Thermochemical Techniques of Boriding , 2018, Current Trends in Boriding.

[9]  M. Elias-Espinosa,et al.  Characterization and boriding kinetics of AISI T1 steel , 2018, Metallurgical Research & Technology.

[10]  S. Taktak,et al.  Characterization and Rockwell-C adhesion properties of chromium-based borided steels , 2015 .

[11]  A. L. Leal-Cruz,et al.  Effect of substrate roughness, time and temperature on the processing of iron boride coatings: experimental and statistical approaches , 2014 .

[12]  I. Gunes,et al.  Kinetics of plasma paste boronized AISI 8620 steel in borax paste mixtures , 2013, Protection of Metals and Physical Chemistry of Surfaces.

[13]  N. Makuch,et al.  Simulation of the growth kinetics of boride layers formed on Fe during gas boriding in H2-BCl3 atmosphere , 2013 .

[14]  A. Erdemir,et al.  Kinetics of electrochemical boriding of low carbon steel , 2011 .

[15]  Pedro Ponce,et al.  Use of fuzzy logic for modeling the growth of Fe2B boride layers during boronizing , 2006 .

[16]  K. Khor,et al.  FeB/Fe2B phase transformation during SPS pack-boriding: Boride layer growth kinetics , 2005 .

[17]  C. Bindal,et al.  An approach to kinetic study of borided steels , 2005 .

[18]  C. Martini,et al.  Mechanism of thermochemical growth of iron borides on iron , 2004 .

[19]  I. Campos,et al.  Kinetic study of boron diffusion in the paste-boriding process , 2003 .

[20]  E. A. Smol'nikov,et al.  Study of the possibility of liquid boriding of high-speed steels , 1982 .

[21]  S. Isakov,et al.  Boriding of steels in gaseous media , 1982 .

[22]  V. Suárez,et al.  Diffusion of Hard Coatings on Ductile Cast Iron , 2013 .

[23]  B. Predel.  B - Fe (Boron - Iron) , 2012 .

[24]  S. Taktak.  Some mechanical properties of borided AISI H13 and 304 steels , 2007 .

[25]  N. Vidakisa,et al.  The VDI 3198 indentation test evaluation of a reliable qualitative control for layered compounds , 2003 .

[26]  G. Sundararajan,et al.  Influence of the pack thickness of the boronizing mixture on the boriding of steel , 2002 .