Mechanical property models for high-strength complex microstructures
This work investigated the relations between the complex microstructures in high-strength steels and their mechanical behaviour, aiming to develop/validate microstructure-property models. Several steel grades were laboratory cast or industrially sampled. The analysed microstructures that were produced on industrial plate and strip mills or in the laboratory and were characterised through different techniques include: precipitation strengthened, quenched and tempered, dual phase, multiphase and TRIP steels. Previous formulations based on physical principles have been refined in order to predict more accurately the stress-strain behaviour of single constituent microstructures. In particular, the equation for ferrite now includes the effect of the internal stresses in DP steels and/or the precipitation strengthening. Several approaches have been used to develop and validate property models for multiphase steels: - for quasistatic tensile properties: - empirical model for the properties in the as-quenched and Q & T conditions, - empirical model in terms of multiphase strains for DP, - analytical self-consistent model, including a correction term for ferrite strengthening, - self-consistent strain model corrected with a multiphase interaction term for ferrite strength that incorporates strain partition (ferrite-martensite), FEM local model, - FEM discrete model for combinations of ferrite-martensite, - iso-E model, - austenite transformation model for TRIP effect; - for toughness, rate dependent FEM models including damage: - continuous models based on the multiphase strain that incorporates nucleation and growth of distributed tensile damage, applied to non-quasistatic tensile and highly notched tensile testing, - discrete FEM model for combinations of ferrite-martensite with an experimental failure criterion, applied to Charpy testing.
Bibliographic Reference: EUR 23181 EN (2008), 208 pp. Euro: 25
Availability: http://bookshop.europa.eu/is-bin/INTERSHOP.enfinity/WFS/EU-Bookshop-Site/en_GB/-/EUR/ViewPublication-Start?PublicationKey=KINA23181 (Catalogue Number: KI-NA-23181-EN-S)
ISBN: ISBN: 978-92-79-07682-4
Record Number: 200910534 / Last updated on: 2009-12-21
Original language: en
Available languages: en