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...

Determination of critical points on hot stress-strain curve of metals is crucial in thermo-mechanical processes design. In this investigation a mathematical modeling is given to illustrate the behavior of metal during hot deformation processes such as hot rolling. The critical strain for the onset of dynamic recrystallization has been obtained as a function of strain at the maximum stress. In a...

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. ...

Human observers easily recognize complex natural phenomena, such as flowing water, which often generate highly chaotic dynamic arrays of light on the retina. It has not been clarified how the visual system discerns the source of a fluid flow. Here we show that the magnitude of image deformation caused by light refraction is a critical factor for the visual system to determine the perceptual cat...

A widely used method for hot forming steels and alloys, especially heavy forging, is the process of multistage forging with pauses between stages. The well-known effect which accompanies multistage hot forging is metal plasticity recovery in comparison with monotonic deformation. A method which takes into consideration the recovery of plasticity in pauses between hot deformations of a billet un...

Among the titanium alloys, Ti-6Al-4V is the most widely used. In the present work, the uniaxial hot compressive behavior of Ti-6Al-4V has been investigated under constant strain rates. A series of dilatometery experiments were carried out to determine the transformation temperatures at different cooling rates. Specimens were homogenized at 1050 °C for 10 minutes followed by fast cooling to dif...

Exotic-deformation effects in 46 Ti nucleus were investigated by analysing the high-energy γ-ray and the α-particle energy spectra. One of the experiments was performed using the charged-particle multi-detector array ICARE together with a large volume (4 " ×4 ") BGO detector. The study focused on simultaneous measurement of light charged particles and γ-rays in coincidence with the evaporation ...