There are mainly two methods of deep drawing analysis: experimental and analytical/numerical. Experimental analysis can be useful in analyzing the process to determine the process parameters that produce a defect free product, and the analytical/numerical modeling can be used to model and analyze the process through all stages of deformation. This approach is less time consuming and more economical. Sheet metal forming often includes biaxial in-plane deformation with non-proportional strain paths. In deep drawing of cylindrical cup, the deformation in the flange is dominated by pure shear deformation, while it changes to plane strain when the material is drawn into the die. This paper deals with the analysis of deep drawing of circular blanks into axi-symmetric cylindrical cup using numerical modeling. The blank drawability has been related both theoretically and experimentally with the initial diameter of the blank and deep drawing parameters. The strains in the radial and circumferential directions have been measured. A correlation on the flange thickness variation by taking into account the work hardening with the analytical and experimental values also has been searched.
Power modules, particularly in hybrid and electric vehicles, have become an essential part of their thermal management system design. In power cooling modules, the temperature variations are important issues, leading to thermal stresses caused by different coefficients of thermal expansion (CTE) in the composite materials. Thus, one should consider suitable materials and manufacturing processes to achieve the best performance and reliability during the device's life cycle. The Cu/CNT-Cu material is assumed to have a unique combination of a high thermal conductivity and low coefficient of thermal expansion, which results in a new composite material that goes beyond the ability of regular materials. To address this, we have developed the Cu/CNT-Cu composite with a significant improvement in thermal conductivity (³327 W/mK) which is within the industrial scale range of copper metal injection molding (320340 W/mK) and low coefficient of thermal expansion (³6 ppm/K), both of which make it an excellent choice for power modules in next generation automobiles. This was achieved by reducing the voids and increasing the interface bonding while adding the copper coated CNTs, which were made by an electroplating process. This mixed Cu/CNT-Cu property makes it the top material design selection in the Ashby map and has a better temperature stability due to its lower thermal distortion parameter (TDP). As a result, this material will represent a significant scientific and technological development in the advancement cooling of IGBT power module devices.
Cast irons are good examples of materials which are more sensitive to chemical composition and production conditions. In this research to improve casting quality, solidification and nucleation process in grey cast iron was investigate. In particular, attempts have been made to rationalize variation in eutectic cells with nucleation sites and eutectic solidification undercooling. Four castings with different diameter and similar chemical composition and pouring temperature and different inoculant percentage was casted. The cooling curve and maximum and minimum undercooling for each castings was measured. Also optical metallography and image analyzer has been used to determine the average eutectic cells diameter, and linear and surface densities, and volume density was calculated. The results of this research show a competitive behavior between nucleation sites and eutectic undercooling. Higher nucleation sites and higher eutectic undercooling cause higher eutectic cell density. But increasing nucleation sites by introducing inoculants to molten metal, is accompanied with reduction in eutectic undercooling. It means that inoculation and undercooling have opposite effect on each other. So, to achieve maximum cell density, it is necessary to create an optimization between these parameters.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.