Motivation for PHS usage Brief History of PHS Usage and Milestones Before the First Automotive Application (1973-1984) More Automotive Applications (1984-2005) Accelerated Use and Globalization (Since 2005) PHS Use in xEVs: Hybrid Electric, Battery Electric, Plug-in...
R-Value, The Plastic Anisotropy Ratio The r-value, which is also called the Lankford coefficient or the plastic strain ratio, is the ratio of the true width strain to the true thickness strain at a particular value of length strain, indicated in Equation 1. Strains of...
N-Value, The Strain Hardening Exponent Metals get stronger with deformation through a process known as strain hardening or work hardening, resulting in the characteristic parabolic shape of a stress-strain curve between the yield strength at the start of plastic...
Necking: Diffuse Neck and Local Neck A tensile bar increases in length as it is pulled, with a concurrent reduction in width and thickness. The cross section is rectangular in shape through uniform elongation. After uniform elongation, however, strains concentrate in...
Total Elongation to Fracture Deformation continues in the local neck until fracture occurs. The amount of additional strain that can be accommodated in the necked region depends on the microstructure. Inclusions, particles, and grain boundary cracking can accelerate...
Forming forces need to exceed the yield strength for plastic deformation to occur and an engineered stamping to be produced. If a metal structure is loaded to a level below the yield strength, only elastic deformation occurs, and the load can be removed. With no...
Stamping and die designers are interested in the forming capabilities of the steels they specify. Complex stampings are created from several different basic forming modes, which are sensitive to different mechanical properties. For this reason, steel formability,...
Engineering stress-strain units are based on the starting dimensions of the tensile test sample: Engineering stress is the load divided by the starting cross-sectional area, and engineering strain is the change in length relative to the starting gauge length (2...
topofpage Sample Size and Shape Tensile Test Procedure Influence of Test Speed Influence of Tensile Test Equipment Tensile testing characterizes the forming and structural behavior of sheet metals. The test involves loading a sample with a well-defined shape along the...
Friction is a restraining force that limits metal flow resulting from contact with another surface during sheet forming. Friction is influenced by the complex interaction between the sheet steel, lubricant, and tooling material, as well as many parameters of the...