In sheet metal forming processes with complex strain paths, a part is subjected to large plastic deformation. This severe plastic deformation leads to high plastic strain localization zones and subsequent accumulation of those strains. Then internal and superficial micro-defects and in other words ductile damage is created. This damage causes quality problems such as fracture. Therefore, design...

Modifying stress-strain curves is one of the important topics in mechanical engineering and materials science. Real stress-strain curves should be modified after necking point as stress becomes three-dimensional after creation of throat, and consequently, equivalent stress should be used instead of axial one. Also, distribution of triple stresses across throat section is not uniform anymore, an...

in this study, the effects cold rolling and annealing parameters during thermomechanical processing of the aisi 201ln stainless steel were investigated. the cast samples were homogenized, hot-rolled and solution-annealed to acquire a suitable microstructure for the subsequent thermomechanical treatment. unidirectional and transverse multi-pass cold rolling at 25, 0 and -15 °c was carried out to...

a nano/ultra-fine grain al-0.2wt% zr alloy was produced by accumulated roll bonding (arb) processafter 10 cycles. the fraction of high angle grain boundaries increased from 8% to 65.4% during 10passes during arb process. this alloy was subjected to tensile test at different temperatures (523,573and 623 k) and strain rates (0.1 and 0.01 s-1). the optimum condition of temperature and strain rate ...

development of an environmental friendly and cost-effective process for microbial degradation of caffeine to non-toxic compounds are promising to solve the problems of physiochemical extraction of caffeine in the treatment the caffeine containing agro-industrial effluents. thirteen bacterial strains, isolated from tea plantation soils in the north region of iran, were screened to show their abi...

the aims of this study were to compare the promoter sequence of the mannose-binding lectin (cmbl) gene in iranian native and commercial chicken strains; as well as to compare the cmbl gene expression in crossbred and inbred chickens. in total 79 native (western azerbaijan native fowls, wanf) and 49 commercial (arian commercial strain, acs) birds were reared as parents under same management prac...

investigating the parameters influencing the behavior of buried pipelines under dynamic loading is of great importance. in this study the soil structure interaction of the pipelines with the surrounding soil was addressed using shaking table tests. wave propagation along the soil layers was also included in the study. the semi infinite nature of the field was simulated using a laminar shear box...

zno thin films were deposited on si(400) substrates by e-beam evaporation technique, and then post-annealed at different annealing temperatures (200-800°c). dependence of the crystallographic structure, nano-strain, chemical composition and surface physical morphology of these layers on annealing temperature were studied. the crystallographic structure of films was studied using x-ray diffracti...

reduced-activation ferritic/martensitic steels have been developed by replacing molybdenum by tungsten and niobium by tantalum in commercial elevated-temperature cr–mo steels to reduce half-life of radioactive isotopes. the objective of this study was to investigate tensile properties of a reduced-activation ferritic/martensitic steel (9cr-2wvta) in normalized-tempered (nt) and quenched-tempere...