Advanced, precipitation strengthened materials created by deformation-induced fine-scale multilayere
The project was focused on the development of novel, re-engineered metallic materials by introducing gradual changes into their microstructures (through a combination of fine precipitates and nano-layers/areas within a typical grain structure), with the main objective to enhance the mechanical properties of these materials through special variations of deformation mode and material microstructure. Application of sophisticated methods and instruments, and the development of advanced theoretical concepts made it possible to build a conceptual and mathematical framework that could be accepted as an in-depth understanding of materials phenomena and its complexity in order to achieve new and unique properties. Constitutive description explaining behavior of deformation-induced fine scale multilayered nanostructures was proposed, and multiscale modeling of microstructure and texture evolutions during monotonic deformation and strain path changes was created.
This project methodology was problem oriented and comprehensive combining interrelated activities of material processing (core activity of the project), characterization, modeling and demonstration. The processing encompasses starting materials (e.g. microalloyed ferrite and austenite) and recently developed by Authors Accumulative Angular Drawing (AAD). Characterization of the advanced precipitation strengthened materials includes detailed description of nano- and microstructures, textures, measurements of mechanical properties and residual stresses. The modeling was carried out at a design combined metal forming process, and for the material response to severe plastic deformation. [if !supportLineBreakNewLine] [endif]
The main outcome of the project was better understanding of the mechanisms occurring within and at the interfaces between the nano/micro layers (areas), as well as their effect on the final advanced multilayered material properties (strength, ductility, toughness). This provides technical guidance for production of the new fine-scale multilayered metallic materials characterized by controlled gradient in both microstructure and properties. This was achieved by a combination of experiments with microstructure-related models.
The main project deliverables are:
a mechanistic and metallurgical description of the evolution of microstructure and properties during combined metal forming process, oriented on the multilayered, ultra-fine structure of investigated metallic systems.
influence of obtained multilayered (micro- and nanolayeres) structures on development of final physical and mechanical properties following severe plastic deformation (SPD) inhomogeneous processing. This was carried out for precipitation strengthened bcc and fcc materials.
a set of mechanism based, material and microstructral constitutive equations, for modeling static and dynamic length scale behavior of fine-scale multilayered materials, encompassing the various length scales and microstructural entities.
a range of modeling approaches, FEM, FEM-CA, MDR, etc. for modeling microstructure development (multilayered fine scale i.e. micro- and nano) and mechanical response of bcc and fcc structures.
multiscale techniques (CAFE, MDR) for bridging length scales from microstructure evolution to deformation process modeling.
regime maps for investigated materials and products to produce optimum processing set-ups and strategies thereby control finescale multilayered structures (quantitatively and qualitatively).
a report detailing findings, guidance and recommendations for optimum structure composition and processing function of final properties of investigated fine-scale multilayered metallic systems.
