LAUSR

Abstract This paper provides several simple but significant formulas that shed light on the connection between the derived transverse stress and some special phenomena, including the premature fracture and largely slant fracture line, occurring during the uniaxial tensile test of sheet metals. Studying two kinds of nearly isotropic materials, theory and simulation analysis found that a non-null transverse stress (σ2) was derived on the tensile specimen after the onset of necking, which grew from 0 and was always less than half of the corresponding longitudinal principal stress. The derived transverse stress was believed to be a primary factor for hindering the development of the neck, promoting the reduction of the thickness, and determining the orientation of the fracture angle. Furthermore, a special necking phenomenon, i.e., crossed necking, was observed during the transition period of the instability in the test and was studied in this paper.