The main objective of this project was to investigate the behavior and the damaging effects of hot tear segregations in the continuously cast steel blooms on the final product quality. To achieve this aim, plant data from three different types of steels were used. Investigations using the scanning electron microscope (SEM) equipped with energy dispersive x-ray spectroscopy (EDS) probe and metal...

the main objective of this project was to investigate the behavior and the damaging effects of hot tear segregationsin the continuously cast steel blooms on the final product quality. to achieve this aim, plant data from three differenttypes of steels were used. investigations using the scanning electron microscope (sem) equipped with energydispersive x-ray spectroscopy (eds) probe and metallog...

Caterpillar has been collaborating with suppliers to analyze steel castings for the tendency to form hot tears using a newly developed damage-based model. The implementation and application of the damage-based hot tear model is presented. The implementation is through an uncoupled simulation of the solidification and deformation problems using commercial software with a user-defined constitutiv...

A hot tear indicator based on the physics of solidification and deformation is presented. This indicator is derived using available data from computer simulation of solidification and solid deformation. Hot tears form when the mushy zone is starved of liquid feeding and deformed in tension. The unfed tensile deformation causes a small additional porosity. A physical model based on a mass balanc...

A three-phase model is presented that predicts solid deformation and damage as well as melt pressure, feeding flow and shrinkage porosity during metal casting. A visco-plastic constitutive theory with damage is used to model the solid deformation. Damage created by mechanically induced voiding is used as a hot tear indicator. The absence of liquid feeding determines when damage starts to form. ...

purpose: to evaluate tear film status and refractive conditions during and one month after treatment of acne vulgaris with isotretinoin (accutane). methods: this prospective study was performed on 26 eyes of 13 known cases of acne vulgaris. all cases were referred by a dermatologist and were candidates for low dose isotretinoin (0.5 mg/kg). full anterior and posterior segment examination and ob...

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...