Elastic behaviour of magnesia-chrome refractories at elevated temperatures

Abstract

An investigation of the high-temperature elastic behaviour of four varieties of magnesia-chrome products was conducted in the present work. The starting materials were characterized with XRF, XRD and SEM/EDS analyses. The measurements of the dynamic Young's modulus were performed in a temperature range of 20-1300°C, using the acoustic method. Moreover, the dynamic Young's moduli, shear moduli and Poisson's ratios were established at ambient temperature for the original and after-heating samples. The obtained results showed similar characteristics, but the elastic behaviours of all the refractory test materials were distinguishable. The curve of the Young's modulus changed as a function of temperature, exhibiting a close-to-hysteresis character, with a decreasing area between the lower and upper curve as the Cr2O3 content increased in the material. The Young's modulus and the shear modulus at ambient temperature were lower for the after-heating samples when compared to the original ones. Keywords: Young's modulus, elastic properties, refractories, shear modulus, Poisson's ratio V tem delu je opisana preiskava visokotemperaturnih elasti~nih lastnosti magnezija-kromovih proizvodov. Za~etni materiali so bili ocenjeni z analizo XRF, XRD in SEM/EDS. V obmo~ju temperatur 20-1300°C so bile izvr{ene meritve dinami~nega Young-ovega modula z akusti~no metodo. Nadalje so bili dolo~eni dinami~ni Young-ov modul, stri`ni modul in Poisson-ovo {tevilo pri sobni temperaturi originalnih in toplotno obdelanih vzorcih. Dobljeni rezultati so pokazali podoben karakter, vendar pa se je elasti~no vedenje vseh preizku{anih ognjevzdr`nih materialov razlikovalo. Krivulja Young-ovega modula se spreminja v odvisnosti od temperature, ima ozek histerezni karakter z zmanj{anjem podro~ja med spodnjo in zgornjo krivuljo, ko vsebnost Cr2O3 v materialu nara{~a. Young-ov stri`ni modul je bil pri sobni temperaturi ni`ji pri`arjenih vzorcih v primerjavi z originalnimi.

Anisotropy of Young's Modulus of DD6 from 25 to 1200 °C Based on Nondestructive Dynamic Method

“…[ 13 ] The dynamic Young's modulus and shear modulus measurements conducted at room temperature were lower than those for the heated samples. [ 14 ] Wolfenden provided a summary of the dynamic Young's modulus and damping characteristics, specifically for the [001] orientation of Ni‐based single crystals. [ 15 ] A new method was used to measure the static and dynamic Young's moduli of long fibers.…”