Community Research and Development Information Service - CORDIS

Abstract

Ferritic or warm rolling is recognised as a very promising and cost-effective way for steel strip processing. This project concentrated on the production of DQ-DDQ steel grades.

Two main processing routes were compared:
- A hot finishing rolling temperature, which ensures recrystallised ferrite in the coiler.
- A low finishing rolling and cooling temperature schedule, which ensures strained ferrite in the coiler. Here, additionally, the possibility of direct annealing was assessed.

For producing a deep drawable ULC-steel, the optimal hot rolling conditions are: reheating temperature of 1050°C, strained hot rolling (rm(measured) = 1.5). The best conditions for an IF(TiNb)-steel are: reheating temperature of 1250°C, strained hot rolling (rm(measured) = 1.9). Isotropic properties of the last combined with an rm-value of about 1.9 were reached for ferritic hot rolling after reheating at 950°C to strained hot strip.

Low temperature ferritic rolling schedule leads to good deep drawing properties for an IF(Ti)-steel after cold rolling and annealing. A hot strip with mean r-value of about 1.5 can be produced through low temperature ferritic rolling and direct annealing treatment.

Deep drawable thin hot strips can be produced from PSi-grades by means of the strained ferritic rolling schedule followed by a direct annealing process. For a MnPSi-steel, an r-value of about 2 is obtained after 85% cold reduction when starting from a recrystallised hot band, while for the strained ferrite rolling process, this maximum is already obtained after 55% of cold reduction.

Additional information

Authors: DE PAEPE A, CRM, Zwijnaarde (BE);AUTESSERRE Ph, IRSID, Maizières-lès-Metz (FR);VASSEUR E, IRSID, Maizières-lès-Metz (FR);HAMMER B, TKS, Duisburg (DE);WUNDERLICH R, TKS, Duisburg (DE)
Bibliographic Reference: EUR 20218 EN (2002), pp.196. Euro: 29.50
Availability: EUR-OP reference: KI-NA-20218-EN-S Available from EUR-OP sales agents. URL: http://eur-op.eu
ISBN: ISBN: 92-894-3256-X
Record Number: 200214796 / Last updated on: 2002-06-11
Category: PUBLICATION
Original language: en
Available languages: en