Effect of substrate roughness, time and temperature on the processing of iron boride coatings: experimental and statistical approaches
by C.I. VillaVelázquez-Mendoza; J.L. Rodríguez-Mendoza; V. Ibarra-Galván; R.P. Hodgkins; A. López-Valdivieso; L.L. Serrato-Palacios; A.L. Leal-Cruz; V. Ibarra-Junquera
International Journal of Surface Science and Engineering (IJSURFSE), Vol. 8, No. 1, 2014

Abstract: The effect of substrate roughness, time and temperature on the formation of iron boride coatings onto AISI-1018 steel substrates by paste-boriding thermochemical (PBT) process has been studied. Three parameters were considered: substrate roughness (0.015, 0.2, 0.8 and 1.2 µm), time (1, 2, 4, 6 and 8h) and temperature (700, 800, 900 and 1,000°C). Coatings were characterised by SEM and XRD; Fe2B and FeB phases were identified. The ANOVA showed that temperature is the parameter with the highest contribution on the iron boride thickness (66.96%), followed by time (15.48%) and substrate roughness (7%). In addition, the interaction of the substrate roughness with temperature and time contributed with 5.7 % to the formation of the iron boride coating. Based on a regression model, an empirical equation and contour levels representing the layer thickness were proposed to estimate the iron boride coatings thickness. The growth kinetic showed that the maximum layer thickness and the minimum activation energy Q = 119.7 kJ/mol are characteristic of a PBT process with substrate roughness of 0.8 µm. Diffusion coefficients and activation energies of each PBT process with different substrate roughness are also given.

Online publication date: Sat, 17-May-2014

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Surface Science and Engineering (IJSURFSE):
Login with your Inderscience username and password:

    Username:        Password:         

Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email subs@inderscience.com