J.Physique IV 8, Pr-8-301-Pr-8-308, 1998


MULTISCALE MODELING OF HIGHLY HETEROGENEOUS PARTICULATE MMCs

A.F. Plankensteiner¹, H.J. Böhm², F.G. Rammerstorfer², H.E. Pettermann³

¹Plansee AG, Reutte/Tyrol, Austria,
²Institute of Lightweight Structures and Aerospace Engineering,
TU Wien, Vienna, Austria
³Austrian Research Centers, Seibersdorf, Austria


Abstract - A continuum mechanics based multiscale modeling concept incorporating different material descriptions at appropriate length scales is presented and applied to High Speed Steels (HSSs) in order to study their overall and local thermomechanical behavior. Such materials can be viewed as particulate Metal Matrix Composites (MMCs) with a strongly clustered arrangement of thermoelastic carbidic particles embedded in a thermoelastoplastic steel matrix.
In the contribution a Mesophase Cell Hierarchical Model is presented, which combines a unit cell approach for handling the clustered topology at the mesoscale with mean field based constitutive material laws (a mean field based version of the Transformation Field Analysis and an incremental Mori--Tanaka approach) for describing the matrix--inclusion-type composite at the microscale. As an alternative approach, a Finite Element based 2/D micromechanical method is used, in which the HSS is modeled as a material with a graded microstructure. Results are discussed in terms of the overall thermoelastoplastic behavior and of microscale parameters relevant for local damage initiation and evolution.


(hjb,990104)