Practical possibilities for the development of steels of mechanical construction and their treatment
The aim of the present research was to investigate the interest and metallurgical possibilities of controlled rolling, including steel composition adaptation, for toughness improvement of 1000 MPa resistance small diameter bars delivered in as-rolled state. The results of pilot scale experiments demonstrate that an excellent set of mechanical properties can be obtained using two different kinds of steel: - 0.4% C steels with Nb and B additions, having mainly perlitic structures - 0.25% C steels with Mo, Nb and B additions, having mainly bainitic structures, and thermomechanical treatments composed of: - finishing temperature below 1000 C and preferably close to 900 C in order to obtain a fine grained and strained austenite after rolling - accelerated cooling between 900 C and 600 C after rolling in order to obtain a low temperature transformation - quasi isothermal holding during transformation in order to avoid formation of martensite.
Bibliographic Reference: EUR 11511 FR (1988) MF, 95 pp., ECU 4, blow-up copy ECU 12.50
Record Number: 198910302 / Last updated on: 1994-12-01
Original language: fr
Available languages: fr