In this research, acheiving submicrocrystalline structure in commercially pure Al is investigated using severe plastic deformation (SPD) method named constrained groove pressing (CGP). In order to find a procedure that acts more effective in grain refinement and mechanical properties enhancement, three experimental procedures were defined and carried out. The procedures were defined by variables of die groove angle (45° and 50°) and using Cu covering sheets at top and down of the specimens instead of rigid die surface as a lubricant. Grain refinement during CGP process was investigated by William-hall analysis on X-Ray diffraction pattern and scanning electron microscopy (SEM). The results show that CGP process in all three procedures can severely refine the microstructure to an ultra-fine grained (UFG) structure with less than 1 micron grain size. Although grain refinement rate in die with 50° groove angle is higher but because of facility of applying extra CGP passes in 45° groove angle die with covering sheets (procedure 2), final grain size in procedure B is lesser. Mechanical properties of CGPed samples was investigated by tensile and hardness tests and the results show that at primary passes in all procedures strength-related properties increases significantly through a decrease in elongation, but at subsequent passes this behaviuor is diffentent for each procedure.

In this paper, the severe plastic deformation method (SPD) known as constrained groove pressing (CGP) was applied to produce ultrafine-grained microstructure in IF steel sheets. In the CGP technique, samples are subjected to repetitive shear deformation under the plane strain deformation condition using the constrained grooved and flat dies. For assessment of microstructure and mechanical properties of the CGPed IF steel sheet, several testing such as: uniaxial tensile test, hardness measurements, scanning electron microscopy (SEM) and X-ray diffraction analysis have been utilized. Finally, it was observed that the grains are significantly refined after the 16-step pressing of the interstitial free (IF) steel sheets. The grains were reduced from 45µm to 243 nm after four passes.

In advanced modern turbines, the temperature of the turbine & apos; s first blade row which is called the turbine & apos; s hot part, increases almost as 1000?. These blades must operate for long periods of time. Since, the main failure reason of the parts operating under high temperature and cyclic loading conditions is fatigue as well as creeping phenomena, acquiring an accurate estimate of these blades & apos; lifetime under creeping and fatigue interactions is very necessary for theoretical and practical requirements. The fatigue of the first blade row of the micro turbine TRI60 is analyzed in this study. For the purpose of estimating the fatigue lifetime of turbine and motor, heat transfer of blades as well as thermal stress is analyzed at first via ABAQUS software. Consequently, a fatigue analysis under full cycle and within the interval of 2/3 v_max to v_max is performed using Smith-Watson-Taper algorithm and transient modal analysis via Fe-safe software.