A CONSTITUTIVE MODEL FOR STRAIN RATES FROM 10^-4TO 10⁶s^-1

Abstract

R6sume' -Nous avons de'veloppe's une a m e ' l i o r a t i o n au modble c o n s t i t u t i f de S t e i n b e r g e t Guinan p o u r l ' a n a l y s e des mate'riaux k t a u x de de'formation u n i t a i r e e'leve'. Nous avons e'tendus l a v a l i d i t e ' de ce mod'ele aux re'gimes o' J l e s t a u x de d 6 f o r m a t i o n a p p r o c h e n t 1 0 -~s -l e t , en exposant du t a n t a l u m au choc, nous avons r e ' u s s i s ' a r e p r o d u i r e un nombre de ph6nom'enes dgpendant au t a u x de d e ' f o r m a t i o n , comme l e p r e ' c u r s e u r de rechoc, l e d 6 c l i n du p r e c u r s e u r , e t l e re'pansion d u choc. Nous avons a u s s i c o n d u i t s une s i m u l a t i o n 2 plaque-choc ob une f o r c e de c h a r g e de 230 GPa f u t applique'e e t nous avons (l'~ork performed under the auspices of the U . S . Department of Energy by the Lawrence ~iverrnore ~a t i o n a l under Contract W-7405-Eng-48

Effect of strain rate on microstructure of polycrystalline oxygen-free high conductivity copper severely deformed at liquid nitrogen temperature

“…This is not surprising since the original model by Steinberg et al (1980) (SCG) was rate-independent and designed for high strain-rate applications. However, the low strain rate extension by Steinberg and Lund (1989) does not lead to good predictions of the yield stress of OFHC copper at low temperatures.…”

“…The Steinberg-Cochran-Guinan-Lund (SCGL) model is a semi-empirical model that was developed by Steinberg et al (1980) for high strain-rate situations and extended to low strain-rates and bcc materials by Steinberg and Lund (1989). The flow stress in this model is given by…”

“…However, this model exhibits an unrealistically small strain-rate dependence at high temperatures. The Steinberg-Cochran-Guinan-Lund (SCGL) model (Steinberg et al (1980); Steinberg and Lund (1989)) is semi-empirical. The model is purely empirical and strain-rate independent at high strain-rates.…”

“…These models are the Johnson-Cook model (Johnson and Cook (1983)), the Steinberg-Cochran-Guinan-Lund model (Steinberg et al (1980); Steinberg and Lund (1989)), the Zerilli-Armstrong model (Zerilli and Armstrong (1987)), the Mechanical Threshold Stress model (Follansbee and Kocks (1988)), and the Preston-Tonks-Wallace model (Preston et al (2003)). We also evaluate the associated shear modulus models of Varshni (1970), Steinberg et al (1980), and Nadal and Le Poac (2003).…”

Effects induced by LHC high energy beam in copper structures

“…The Johnson-Cook (J-C) model [23] is purely empirical and it is one of the most widely used. Examples of semi-empirical models are the Steinberg-Cochran-Guinan-Lund (S-C-G-L) model [24], which was first developed for the description of high strain-rates behaviour and later extended to low strain-rates, and the ZerilliArmstrong (Z-A) model [25], that is obtained on the basis of the dislocation mechanics theory and presents a different formulation for BCC and FCC materials. A more complex dislocation based model is the Mechanical Threshold Stress (MTS) model [26].…”