Numerical solutions of metal plastic flow in compression tests with sinusoidal profile of die roughness
Keywords:Compression test, FEM, Microforming, Size effect, Rough friction
During metal bulk-forming in microscale the so-called size effect, making changes in the material deformation process should be taken into account. One of the factors having a significant influence on the flow mechanics is a die roughness. Paper contains results of numerical analysis of the cylindrical sample compression between anvils with sinusoidal profile of roughness and with zero friction factor at the tool-workpiece interface in dry conditions. Two models of dies were used: parallel and conical one. Obtained data were compared to analogous, conventional models of compression tests with flat dies and with constant friction factor – equivalent to sinusoidal wave. Sinusoidal curve modeling the die roughness was determined from the surface roughness profile and using the motifs method. Presented analysis revealed increase in value and in variability of stress and strain in layers flowing in the vicinity of the wave – size effect. No impact of the wave presence on the compression forces values was obtained.