Author : Eric Brizes
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (135 download)
Book Synopsis Generalization of Metallurgical and Mechanical Models for Integrated Simulation of Automotive Lap Joining by : Eric Brizes
Download or read book Generalization of Metallurgical and Mechanical Models for Integrated Simulation of Automotive Lap Joining written by Eric Brizes and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The automotive industry wants to advance integrated computational materials engineering (ICME) approaches that combine models of joining processes and microstructural evolution for prediction of material property gradients and ultimately the mechanical performance of multi-sheet lap joints. Despite the increasing demand for computational optimization within vehicle structures and the increased use of low-density materials, modern integrated modeling frameworks of automotive lap joining are often limited to the resistance spot welding (RSW) of conventional steels. Moreover, important phenomena in steel weldments, like decomposition of austenite on-cooling, tempering of martensite, and microstructure-dependent flow stress and damage properties are too material-specific for universal application. In this research, generalized metallurgical and mechanical modeling strategies are investigated for increased applicability to a wider range of steels and joining processes. The study evaluates: the reliability of heat transfer predictions within state-of-the-art numerical models of RSW, the accuracy of existing austenite decomposition models, the readiness of steel time-temperature-transformation (TTT) diagram tools containing CALPHAD-calculated parameters, the generality of a recently developed martensite tempering model, and the determination of RSW fusion and heat-affected zone flow stress and fracture behavior. Results show that state-of-the art finite element models of RSW that are validated using experimental weld nugget dimensions have a propensity to underpredict cooling rates. A JMAK and additivity rule approach calibrated with experimental TTT diagram data exhibited the greatest accuracy when predicting AHSS austenite decomposition; however, calibrations using calculated TTT diagrams better facilitated material optimization. Generalized parameters within a JMAK-type model of martensite tempering successfully predicted HAZ softening within martensitic and dual-phase steel weldments. And a flow stress scaling approach coupled with a simple relation of hardness to true fracture strain to estimate microstructure-specific plasticity and damage allowed for adequate simulation of RSW tension-shear destructive testing. The overall aim was to contribute to the infrastructure and implementation of ICME within the automotive industry by generalizing modern microstructural modeling strategies to facilitate future materials engineering.
