Direct Spheroidization of High Carbon Steels: Effect of Thermomechanical Processing

Matteo Caruso; Hector Verboomen; Stéphane Godet

doi:10.4028/www.scientific.net/SSP.172-174.922

Paper Titles

Thermodynamic Analysis of the Effect of Compositional Inhomogeneity on Phase Transformations in a 13Cr6Ni2Mo Supermartensitic Stainless Steel
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The Structure and the Evolution of Titanate Nanobelts, Used as Seeds for the Nucleation of Hydroxyapatite at the Surface of Titanium Implants
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Restitution of the Shapes and Orientations of the Prior Austenitic Grains from Inherited Alpha' Orientation Maps in Steels
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Phase Transformations on Friction Welding of Dissimilar Thermochemically Treated Steels
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Direct Spheroidization of High Carbon Steels: Effect of Thermomechanical Processing
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Group Theory Considerations in Quasicrystal to Crystal Transformations
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Quasicrystalline Phase Transformation in the Quaternary and Ternary Systems AlCuMnFe and AlPdMn
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Hydrogen-Storage Properties of Nanocrystalline Mg-Based Materials Created through Controlled Devitrification of a Metallic Glass
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Phase Transformations in Amorphous Bilayer Ribbons
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HomeSolid State PhenomenaSolid State Phenomena Vols. 172-174Direct Spheroidization of High Carbon Steels:...

Direct Spheroidization of High Carbon Steels: Effect of Thermomechanical Processing

Abstract:

The eutectoid transformation of austenite can occur cooperatively (pearlite transformation) or by means of a non-cooperative mode (Divorced Eutectoid Transformation). In the cooperative mode, ferrite and cementite grow together, leading to the typical lamellar microstructure of pearlite. In the non-cooperative mode, spheroidal cementite particles grow directly from the undissolved carbides in the austenite phase. The transformation product is a fully spheroidized microstructure. In this study, the parameters promoting the occurrence of DET in a hypereutectoid steel (austenitization temperature, cooling rate, presence of proeutectoid cementite in the initial microstructure) were investigated. It is shown that low undercooling levels and a homogenous distribution of fine carbides in the austenite promote the DET over the lamellar transformation mode. The spheroidized microstructures produced by DET lead to larger ductilities comparing to those obtained by the lamellar transformation mode.