Effect of heat treatment temperature on thestructural evolution of hot forged steel balls used forgrinding raw material in cement industry

Année : 2018
Domaine : Sciences des matériaux
Type : Communication
Conférence: 6th International Conference on Welding, Non Destructive Testing and Materials Industry (IC-WNDT-MI’18)
Résumé en PDF :  (résumé en pdf)
Fulltext en PDF :  (.pdf)
Mots clés : grinding balls, forging, heat treatment, characterization, XRD analysis, Rietveld refinement

Résumé : 

The raw material preparation sector such as cementworks, the steel and mining sector is beginning to pay attention toforged balls as an alternative to the cast balls for their best usecharacteristics. The forging materials are stronger than thecasting material because of their fiber structure. The forgingtechnique, in contrast to the casting process, contributes to asignificant improvement of ball wear behavior during thegrinding process.The wear behavior depends on several factors including thechemical composition of the alloy, the type of microstructure andthe applied heat treatment. In this work we focus on the effect ofaustenitizing temperature on the type of the producedmicrostructure. Al the heat treatment parameters were fixed forall the samples except the austenitizing temperature. Threeaustenitizing temperatures are selected and a tempering at 250°C with a holding time of one hour followed by cooling has beencarried out. The study is carried out on medium micro-alloyedcarbon steel intended for heat treatment.To make clear the effect of the temperature on themicrostructural transformation, several investigations wereachieved. Optical and SEM microscopy was carried out toqualitatively characterize the phases A microstructural analysisusing the Rietveld method was conducted to access, for eachtemperature, the type and proportion of phases as well as thecrystallites size.