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Surface morphology of a high strength low alloy steel is analyzed on wire electric discharge machining (WEDM) process with a cold-treated (CT) brass wire. Cold treatment process is carried out at − 70 °C for 24 h to refine the microstructure of brass wire for smooth discharge energy during machining process. Fractional factorial design is used to measure the response of recast layer thickness (RLT), wire material infusion (WMI), and micro-hardness (MH) of hardened HSLA steel. CT brass wire, servo voltage (SV), pulse on time (Ton), pulse off time (Toff), wire tension (Tw), and flushing pressure (Fp) of deionized water are selected as input process parameters. Analysis of variance (ANOVA) is performed to test the adequacy and significance of the developed mathematical models. Ton is observed as the most effective input process parameter followed by Toff and CT brass wire. Low-energy parameters with CT brass wire exhibits results with reduced RLT and WMI on machined surface as compared to NCT brass wire. CT brass wire is less wear off with respect to NCT brass wire while machining workpiece at same input process parameters. [ABSTRACT FROM AUTHOR]

To increase the limiting drawing ratio (LDR) in deep drawing, experiments are conducted on DP600, IF, and HSLA steels. The flange region of blank is heated up to temperatures in the warm range by inductance heating. During heating, the central portion of blank is cooled by water to prevent the reduction of the strength of the material in the central region. The temperature increase of flange region is observed by two infrared sensors focusing on two different points, one on the blank rim and the other near the die radius. An intensive cooling by cold water is applied to the bottom side of a blank during deep drawing. Increases up to 25.58% on LDR are obtained. There is no significant change in the microstructure of the material due to warm forming. Material characterization is obtained by a Gleeble 3800 thermo-mechanical testing machine for the temperature range 150-300 °C. [ABSTRACT FROM AUTHOR]