the effects of carbon content on the dynamic and static softening mechanisms of ti microalloy steels were investigated both in ferrite and austenite regions. the results obtained showed that recrystallization rate decreased as the percentage of carbon content was increased from 0.0035 to 0.110. this is due to the ti(cn) and tic precipitates and also the free carbon content. in the ferrite regio...

A physically-based two-site mean field model has been developed to describe the microstructural evolution due to recrystallization during and after deformation. The model has been applied to predict the recrystallized fraction, recrystallized grain size, and flow stress of 304L austenitic stainless steel during discontinuous dynamic recrystallization (DDRX), post-dynamic recrystallization (PDRX...

Purpose: A study on the hot deformation behaviour and dynamic structural processes (dynamic precipitation operating during deformation at elevated temperatures) of nickel based superalloy was presented. Design/methodology/approach: Compression tests were carried out on precipitations hardenable nickel based superalloy of Inconel 718 at constant true strain rates of 10-4, 4x10-4s-1 within a temp...

P. Kawulok, I. Schindler, R. Kawulok, S. Rusz, P. Opěla, J. Kliber, M. Kawuloková VSB – Technical University of Ostrava, Faculty of Metallurgy and Materials Engineering, Czech Republic Z. Solowski, K.M. Čmiel Třinecké železárny a.s., Czech republic Formability of hypereutectoid C-Mn-Cr-V steel in hot condition was investigated with use of plastometric methods. A wide range of deformation temper...

The Sellars and Tegart’s hyperbolic sine constitutive model is widely practiced in describing stress–strain curves of metals hot deformation processes. acceptance this phenomenological owed to its versatility (working for a wide range stress values) simplicity (being only function strain, strain rate, temperature). common practices are revisited work, with few suggestions improve results. Moreo...

A viscoplastic deformation model considering material damage is used to predict hot tear formation in a permanent mold magnesium alloy casting. The simulation model calculates the solid deformation and ductile damage. The viscoplastic constitutive theory accounts for temperature dependent properties and includes creep and isotropic hardening. Ductile damage theory is used to find mechanically i...

Experiments were carried out in which the dependence of the fractional softening on temperature, time and strain rate was determined in a 304H stainless steel. Three prestrain ranges were identified pertaining to three different post-deformation softening behaviors: 1) prestraining to below the DRX critical strain: strongly strain dependent softening by SRX alone with softening kinetics control...

To investigate the hot deformation behavior of 17-7 PH stainless steel, hot compression tests were carried out at the temperatures of 950, 1050 and 1150 oC and strain rates of 0.001 s-1 to 0.1 s-1. Accordingly, the hot working behavior was studied by the analyses of flow stress curves, work hardening rate versus stress curves, exponent- type constitutive equations and deformed microstructures. ...