Hot rolling: mechanical, microstructural, modeling, simulation for both ferrous and light metals

The dimensions, speed and complexity of rolling mills have been advancing with understanding of the mechanics and augmented calculating power. However, the metallurgical mechanisms both during the passes and between them are significant for stresses, defect avoidance and product properties. With facile ability to examine microstructures at end of any pass or interval, physical simulation of multistage rolling has been achieved in torsion, as well as in plane strain compression; while the former excels in number of passes and total strains ε, the latter can provide texture information. However, for product mechanical properties, torsion only permits hardness of the surface layer while plane strain specimens would permit tension or bending. From dependencies on strain, strain rate and temperature T of stresses and microstructure for Al alloys, C/HSLA/tool steels and ferritic/austenitic alloys, the dependence on microstructural mechanisms during straining and unloaded intervals can be clearly defined and related to rolling forces and power demands. The effects of solute, particles and lattice dependent dislocation mobility can provide understanding of broad range of industrial requirements for product properties. For C/HSLA steels, there is the added complexity of adding a cooling procedure that ensures planned phase transformations. For Al alloys and stainless steels, the final cooling schedule can be arranged to provide prevention of, or any degree of static recrystallization, with control of grain size and degree of isotropy. The multistage rolling simulations combined with examination by optical microscopy OM, TEM and SEM-OIM improve process controls and product properties.