Effects of temperature and strain rate on the tensile properties of twip steels

Abstract

Three high manganese TWIP steels were produced with stacking fault energies γ SFE ranging from 20.5 to 42 mJ/m 2 . The materials were mechanically tested in tension at temperatures and strain rates varying in the ranges of -50°C…80°C and 10 -3 s -1 …1250 s -1 , respectively. Due to the temperature dependence of γ SFE , also the mechanical behavior of TWIP steels reveals clear temperature dependence, determined by the prevailing deformation mechanism, i.e., dislocation slip, deformation twinning, or ε-martensite transformation. In addition to the 'ordinary' strain rate sensitivity, an increase in temperature due to adiabatic deformation heating contributes to the stacking fault energy (SFE) at high strain rates, shifting γ SFE towards the dislocation slip regime and this way strongly affecting also the mechanical behavior. At stacking fault energies close to the transition between twinning and ε-martensite transformation, lowering the temperature can ultimately result in entering the ε-martensite transformation regime that may bring about further ductility.

Microstructural changes and strain hardening effects in abrasive contacts at different relative velocities and temperatures

“…The temperature has a crucial influence on the strain hardening in tensile tests [58]. In tribosystems at comparatively low loads the strain hardening behaviour is similar at RT and 500°C.…”

Influence of Temperature on Mechanical Properties, Fracture Morphology and Strain Hardening Behavior of a 304 Stainless Steel

“…The formation of α' martensite is highly influenced by the SFE and the chemical driving force to transform austenite to martensite. Since both parameters are dependent on temperature, this variable also affects SIMT 6,7 . There are already some works on the technical literature dealing with the sensitivity of strain hardening to temperature.…”

Properties and Structure of X30MnAlSi26-4-3 High Strength Steel Subjected to Dynamic Compression Processes

“…The temperature rise due to work required for the plastic deformation of the specimen was determined using the formula (5) [14]:…”

“…The data of temperature rise due to the conversion of work needed for the plastic deformation of high-manganese steels has been published in works [14,15]. In [14] the reported increase in temperature was 95°C during dynamic tensile test of TWIP steel at strain rate of 1250 s -1 and in [16] the increase was 17°C during compression at rate of 700 s -1 and 54°C at 2500 s -1 , the presented data are similar to the results obtained in this work. High strain rate leads to the local instability of the material in the form of shear bands [17,18].…”