Structure and thermal expansion of (Cr-x,V1-x)(n+1)AlCn phases measured by X-ray diffraction
2017 (English)In: Journal of the European Ceramic Society, ISSN 0955-2219, E-ISSN 1873-619X, Vol. 37, no 1, 15-21 p.Article in journal (Refereed) Published
MAX phases in the (Crx,V1-x)(n+1)AlCn,system were synthesized by reactive sintering or hot isostatic pressing of elemental powders at temperatures between 1400 degrees C and 1600 degrees C. For n=1, a complete range (0 amp;lt;= x amp;lt;= 1) of solid solutions was found; for n=2 and 3 the solubility ranges were 0.25 amp;lt;= x amp;lt;= 0.75 and 0 amp;lt;= x amp;lt;= 0.5, respectively. Powder X-ray diffraction revealed that the lattice parameters of all (Cr-x,V1-x)(n+1)AlCn solid solutions followed Vegards law. The thermal expansion coefficients of the various compounds were determined from Rietveld refinements of X-Ray patterns obtained at temperatures between ambient and 800 degrees C. For the n=1 and 3 phases the thermal expansion coefficients were almost isotropic; those for the n=2, however, were quite anisotropic with the expansion along the a-axis being significantly larger than along the c-axis. As a general trend, vanadium rich compounds have smaller thermal expansion coefficients than their Cr-rich counterparts. (C) 2016 Elsevier Ltd. All rights reserved.
Place, publisher, year, edition, pages
ELSEVIER SCI LTD , 2017. Vol. 37, no 1, 15-21 p.
MAX phases; Thermal expansion; Carbides; Solid solutions; XRD
IdentifiersURN: urn:nbn:se:liu:diva-132463DOI: 10.1016/j.jeurceramsoc.2016.07.022ISI: 000384852400002OAI: oai:DiVA.org:liu-132463DiVA: diva2:1046285