A Novel Heat Treatment Line for Processing of Tailored Small Batch Steels

Abstract:

This study describes design and construction of a novel flexible heat treatment line for processing customer-oriented small batch steels. The induction heater (600 kW) developed is suitable for the sheet thickness in the range 3.2 30 mm and the width of 85 1250 mm. Sheets are fed using an electrical motor (1.5 kW) and a chain drive, the speed being in the range 0.3 7 m/min, depending on the power and the sheet dimensions. At this study, 4.5 (WR-1) and 10 mm (WR-2) thick wear resistant steels were tempered at different peak temperatures to compare the effect of rapid tempering on mechanical properties. Results showed that the heat treatment line is capable of producing tempered steel grades with adequate properties at industrial product rate. For example, 4.5 thick WR-1 tempered at 550 oC provided a yield strength (YS) over 1000 MPa with minimum bending radius of 6 mm (in the delivered condition YS = 1605 MPa and R_min = 12). Tempering of WR-1 at 700 oC provided YS of 762 MPa and R_min of 1 mm. Results were similar between two test materials, but the enhancement in bendability was slightly more effective with the thinner sheet.

• Periodical: Key Engineering Materials (Volumes 611-612)
• Pages: 804-810
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.611-612.804
• Online since: May 2014
• Authors: Antti Järvenpää*, Janne Lämsä, Emmanuel Patard, Kari Mäntyjärvi
• Keywords: Induction Heating, Local Heat Treatment, Rapid Annealing, Short Tempering, Tailored Steels

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