Air cooled bainitic steels for strong, seamless pipes Part 1 – alloy design, kinetics and microstructure
نویسندگان
چکیده
Seamless pipes are usually quenched and tempered after manufacture in order to obtain the desired properties. The possibility of avoiding this heat treatment is explored here, by designing steels which transform into an carbide free bainitic microstructure during cooling from the hot processing phase of the pipe. The cooling conditions studied are appropriate for the manufacturing process and care has been taken to ensure that the correct microstructure is generated for the range of cooling rates experienced in industrial practice. The alloy design has been validated by kinetic and microstructural studies.
منابع مشابه
Air cooled bainitic steels for strong, seamless pipes Part 2 – properties and microstructure of rolled material
In the first part of the present study, two steels were designed with the aim of achieving properties consistent with the specifications for the manufacture of seamless pipes. The alloys were intended to develop into mixtures of bainitic ferrite and carbon enriched retained austenite during cooling to ambient temperature from the pipe forming operations, thus avoiding the need for subsequent he...
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