Integrated computational- experimental program for
ductility and failure in cast aluminum alloys
Sponsor: National Science Foundation GOALI Grant
PI: S. Ghosh, Co-PI: B. Mazumdar, S. Harris, J. Boileau
Keywords: Cast Aluminum alloys, Ductility, image-based microstructural Voronoi cell FEM, Quantitative metallography
Abstract:
The automotive industry is faced with major challenges to improve performance and reduce weight in order to meet lofty fuel efficiency and emissions standards at low cost. As designs become more complex and the power output requirements increase, practical limits of ductility and ultimate strength are being reached. Scrapped parts and downtime can cost a manufacturer millions of dollars. The proposed Industry-University Collaborative GOALI research is aimed at addressing this issue. It will build a relation between Ohio State University (PI), New Mexico Institute of Technology (Co-PI) and Ford Research Laboratory (Co-PI and industry partner) to launch an integrated experimental-computational research program. The program will augment a major thrust area at Ford to reduce development time, improve quality and performance, reduce scrap and weight, and reduce costs.
The proposed program is aimed at developing a system of experimentally motivated and validated adaptive multiple scale computational models for predicting localization and ductile fracture of cast Al-Si components from microstructural information and process conditions. The models will simulate the evolution of microstructural features such as voids and secondary phases into incipient cracks and determine how ductile failure depends on alloy properties and on the distributions and interactions of different phases in the microstructure. The mechanics of particle fracture, interface decohesion, matrix rupture and damage percolation through the dendritic network will be studied in detail. The role of porosity size and distribution on failure will also be investigated. The program is anticipated to aid the design of new processes that circumvent these failure mechanisms and are more robust to process variability. Developmental modules will include: (i) Quantitative metallography using SEM, orientation imaging microscopy (OIM), and microstructural characterization to identify and characterize critical microstructural; (ii) Mechanical tests with in-situ SEM observation to generate strain fields and to provide understanding of critical mechanisms in the failure process; (iii) Neutron diffraction and Raman microprobe for microstress evolution and probabilistic strength estimation of particles; (iv) Development of an adaptive multi-level model for multiple scale analysis to predict the failure process as a phenomenon of multi-scale incidence and propagation of cracks; (v) Development of image-based microstructural Voronoi Cell finite element model for efficient and accurate analysis of plastic deformation, strain localization and damage evolution in nonuniform heterogeneous microstructures; and (vi) Incorporation of a probabilistic analysis framework to account for the effect of input variabilities on ductility and failure.
OSU Research Team
Professor: S. Ghosh,Graduate Students: A. Tiwary, V. DakshinaMurthy, J. Bai, H. Chao
External Research Team
Professors: B. MazumdarDrs. S. Harris, J. Boileau (Ford Research Laboratory),
Research Partners
New Mexico Institute of TechnologyFord Research Laboratory