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Production of hot rolled thin gauge steel strip in a compact six-stand mill was studied by means of mathematical modelling and on site measurements. Data obtained during processing low carbon steel strip ranging from 1.06 to 2.68 mm in final outgoing thickness included speeds, reductions and separation forces at each of the six stands. The mean flow stress during rolling was calculated from the rolling loads, assuming adhesive conditions within the roll-gap, and by means of a mathematical model that accounts for strain hardening and the occurrence of various dynamic restoration phenomena during deformation. It was found that the values of the mean flow stress values, independently of the way they were obtained, varied as a function of both, strain rate and temperature, being possible to derive a unique formulation to describe their behaviour.

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Traditional 11·5 wt-%Cr ferritic stainless steels are single stabilised with Ti or dual stabilised with Ti–Nb additions. A dual-stabilised ferritic stainless steel 409 with Zr–Ti additions was studied, which was selected through thermodynamic and kinetics analysis. The alloy was subjected to thermomechanical processing using both hot and cold rolling and annealing. The intergranular corrosion resistance and microstructure of this alloy was evaluated. Of particular interest was to study the stabilisation behaviour of this alloy under all processing conditions. The results showed that the precipitation of CrxCy was effectively prevented; hence, the alloy used in this investigation had an excellent resistance to intergranular corrosion.

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A systematic variation of the parameters involved in the spot welding by electrical resistance of galvannealed strips was carried out on samples from a 2 mm thickness galvannealed high strength low alloy steel strip used for automotive applications. The varied parameters in the present study were welding current, welding time, holding time after welding and number of welding pulses, while the dimensions and characteristics of the electrodes and the applied force during welding were kept constant. The wear of the electrodes is important, however it was not the aim of the present study, therefore it was not taken into account. The experimental results were analysed to evaluate the influence of the various parameters on diverse characteristics of the welded bead. It was possible to determine the optimal operational conditions for this particular type of material.

The following paper explores the hot-flow behavior of Inconel 718 subjected to delta processing (DP), with various microstructures obtained by means of carrying out an initial billet forging operation prior to the heat treatment and final deformation tests. Hot compression tests were subsequently performed at 960 °C and 1020 °C at the four different strain rates of 0.001, 0.01, 0.1, and 1 s -1 . The two deformation temperatures recorded were 960 ºC and 1020 ºC, located below and above the -solvus of IN718 respectively. Microstructural characterization was performed by means of optical (OM) and scanning electron microscopy (SEM).SEM examinations suggest that the existence of the -phase prior to the application of the high deformation temperature may results in the fragmentation of the existing -phase by means of partial dissolution and/or deformation, leading to an improved grain size control.The A general classic dynamic recrystallization (DRX) behavior was observed in the flow curves, which is typical of low-medium stacking fault energy (SFE) alloys., with Tthis flow behavior was modeled according to various approaches and the results compared. Peak stress modeling was performed using two different approaches, referred to as 'apparent' and 'physically-based'. The hot-flow behavior before the peak stress was modeled according to the Estrin-Mecking-Bergstrom approach, with Avrami kinetics employed to describe the DRX behavior.

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