Fraunhofer Institute for Mechanics of Materials IWMEffect of GKZ annealing of wire rod made from cold-formed steels on the degree of microstructural alignment
Experimental investigation and materials-specific description of the effect of GKZ annealing of cold-formed steel wire rod on the degree of structural alignment and its influence on processing-relevant mechanical and technological properties
Completed research project
Project description
This research project investigated methods and processes for influencing the microstructure alignment of cold-formed steels through targeted heat treatment processes. Initially, this was done under controlled laboratory conditions, with the transformation to industrial production to follow later.
Fraunhofer IWM subproject:
- Analysis of the microstructure and quantification of microstructure parameters (microstructural linearity, grain size, etc.) for samples from different process routes
- Analysis of the formation of secondary and tertiary linearity and the relevant interactions regarding the avoidance of linearity
- Analysis of damage mechanisms for different process routes, steels, and loads
- Simulation of the effects of property anisotropy due to microstructural alignment
- Correlation between process route, microstructure (focus on anisotropy, especially microstructural alignment), and mechanical materials properties relevant to processing
- Validation of the correlation on relevant critical components
Transfer of project results to the following Fraunhofer IWM R&D services for companies:
- Quantitative microstructure evaluation of light microscopy images: grain size statistics, phase segmentation, quantitative lineality measurement
- Quantitative evaluation of EDX maps
- In situ tracking of local strains in the etched microstructure during a microtensile test
- Practical knowledge expansion:
- Correlations between process parameters, microstructure, and mechanical properties
- Damage mechanisms in cold forming
- Influence of microstructure linearity on ductile damage
