Soyarslan, C.Tekkaya, A. E.Manufacturing EngineeringDepartment of Mechatronics Engineering2024-07-052024-07-052009151611-368310.2374/SRI08SP1702-s2.0-70350416981https://doi.org/10.2374/SRI08SP170https://hdl.handle.net/20.500.14411/1493Tekkaya, Erman/0000-0002-5197-2948; Soyarslan, Celal/0000-0003-1029-237XIn the context of forward bulk extrusion, where product defects are frequently observed, the effect of counter pressure on damage accumulation materializing a Continuum Damage Mechanics (CDM) approach is presented. A Lemaitre variant damage model accounting for unilateral damage evolution coupled with a multiplicative finite plasticity is utilized for this purpose. After a presentation of the crack governing mechanism, it is demonstrated that application of counter pressure introduces a marked decrease in the central damage accumulation, which in turn increases the formability of the material through keeping the tensile triaxiality in tolerable limits. It is also shown that, for a crack involving process, through systematic increase of the counter pressure, the crack sizes diminish; and at a certain level of counter pressure chevron cracks can be completely avoided.eninfo:eu-repo/semantics/closedAccessforward extrusioncounter pressurechevron cracksductile damagefinite elementsArticleQ2Q3809671679WOS:000269856200011