A power-based approach to assess the barrelling test’s weak solution

Physical simulation of forming is an analytical-experimental branch of mechanical science. Carefully formulated models and their solutions are essential to interpret the simulation data meaningfully and to understand its underlying phenomena. Oversimplified models of deformation and their associated non-unique closed-form solutions are widespread due to the complex and path dependence nature of plastic deformation, its multi-layered governing equations and boundary conditions. Therefore, it is vital to critically evaluate these models at the kinematic level to ensure a reliable outcome

Stress Corrosion Cracking of Novel Steel for Automotive Applications

AbstractIn the present study, susceptibility of a high manganese TWIP steel to stress corrosion cracking (SCC) in a 3.5% NaCl solution was investigated using slow strain rate tests (SSRT), constant load (CL) tests and fractography. Strain rates employed for SSRT were in the range of 10-06 - 10-08 s-1. The specimens tested in air revealed a ductile type of failure, whereas those tested in the corrosive solution exhibited a brittle feature that is attributed to stress corrosion cracking. SCC was observed at a relatively low strain rate of 10-07s-1

Evaluation of barreling and friction in uniaxial compression test: A kinematic analysis

Barreling compression test is an important tool for characterizing the mechanical responses of deformed material. This test also serves for studying the interfacial friction between the tool and workpiece, based on the only available method of Avitzur's “limit analysis of disc and strip forging”. This method was found to be satisfactory for low friction conditions; however, it has remained to be examined in depth. In the present work, Avitzur model is thoroughly investigated, and its applicability and limitations are discussed. Along these lines, the kinematics of Avitzur model are presented to be used in describing both the barreling parameter of the model and the profile of the deformed sample. Following an exhaustive examination on the barreling parameters of various deformed samples, one of the methods is identified to be valid for evaluating friction factor up to m ≤ 0.5. Moreover, the results clearly show that the model has its highest accuracy as long as the side-surface folding phenomenon is negligible (≤ 0.25%)