Structure and properties of low temperature plasma carburized austenitic stainless steels


Autoria(s): Souza, Roberto Martins de; IGNAT, M.; PINEDO, C. E.; Tschiptschin, Andre Paulo
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

18/10/2012

18/10/2012

2009

Resumo

Austenitic stainless steels cannot be conventionally surface treated at temperatures close to 550 degrees C due to intense precipitation of nitrides or carbides. Plasma carburizing allows introducing carbon in the steel at temperatures below 500 degrees C without carbide precipitation. Plasma carburizing of AISI 316L was carried out at 480 degrees C and 400 degrees C, during 20 h, using CH(4) as carbon carrier gas. The results show that carbon expanded austenite (gamma(c)), 20 mu m in depth, was formed on the surface after the 480 degrees C treatment. Carbon expanded austenite (gamma(c)), 8 mu m in depth, was formed on the surface after the 400 degrees C treatment. DRX results showed that the austenitic FCC lattice parameter increases from 0.358 nm to 0.363 nm for the 400 degrees C treatment and to 0.369 nm for the 480 degrees C treatment, giving an estimation of circa 10 at.% carbon content for the latter. Lattice distortion, resulting from the expansion and the associated compressive residual stresses increases the surface hardness to 1040 HV(0.025). Micro-scale tensile tests were conducted on specimens prepared with the conditions selected above, which has indicated that the damage imposed to the expanded austenite layer was more easily related to each separated grain than to the overall macro-scale stresses imposed by the tensile test. (C) 2009 Elsevier B.V. All rights reserved.

Identificador

SURFACE & COATINGS TECHNOLOGY, v.204, n.6/Jul, p.1102-1105, 2009

0257-8972

http://producao.usp.br/handle/BDPI/18248

10.1016/j.surfcoat.2009.04.033

http://dx.doi.org/10.1016/j.surfcoat.2009.04.033

Idioma(s)

eng

Publicador

ELSEVIER SCIENCE SA

Relação

Surface & Coatings Technology

Direitos

restrictedAccess

Copyright ELSEVIER SCIENCE SA

Palavras-Chave #Plasma carburizing #Expanded austenite #Micro-scale tensile tests #MECHANICAL-PROPERTIES #EXPANDED AUSTENITE #CRACKING #ADHESION #BEHAVIOR #Materials Science, Coatings & Films #Physics, Applied
Tipo

article

proceedings paper

publishedVersion