Computational Studies for the Yield-Point Phenomenon of Metals

Abstract

The yield-point phenomenon (YPP) is an accustomed topic in sheet metal forming fields. Over hundred and fifty years since the first observation of the YPP, many research efforts have been continued to understand and describe it. Recent spotlights for the YPP studies are focusing on high-degree numerical methods with the support of increasing computing performance. Here, we review the representative computational studies on YPP to share the latest progress and remaining challenges to obtain better mechanical insights into it. After the duality of the YPP is addressed in terms of avoiding and utilizing it, the constitutive material models for the YPP as well as bake hardening models are discussed for a continuum level FE simulations, and the features of the discussed YPP models are compared. Microscopic and multiscale schemes are also briefly handled. It is expected that more advanced computational work can be initiated from this review.

Indentation Modulus, Indentation Work and Creep of Metals and Alloys at the Macro-Scale Level: Experimental Insights into the Use of a Primary Vickers Hardness Standard Machine

“…The mechanical behavior of a metallic material, for example in terms of plastic deformation and elastic recovery, cannot always be univocally identified from Hooke’s law, since certain dependences on the applied force time/rate (static, quasi-static, dynamic, and impulse), the type of acting forces (compression, tension, torsion, and penetration), the stressed surface area, the investigated scale (from the nanoscale to the macroscale level), beyond the usual environmental conditions (temperature), and the effects of aging (oxidation and corrosion) often induce some deviations from the expected linearity [ 1 , 2 , 3 , 4 , 5 ]. Therefore, it is more appropriate to identify, from time to time, a specific experimental technique tailored to the actual application of the investigated metallic material, to provide a suitable characterization of its mechanical properties in terms of elastic and plastic behavior.…”