Structure and mechanical properties of low-carbon steel for oil and gas pipelines

Abstract

The structure and mechanical properties of low-carbon microalloyed pipe steel are studied. Different heat-treatment systems permit the regulation of microstructure formation and modification of the strength. A complex structure with minimal content of acicular components is observed in the steel after quenching from the austenite region at the cooling rate typical of pipe treatment and high tempering. The best combination of structure and mechanical and corrosion properties is obtained after heat treatment that includes double quenching (first from the austenite region and then from the intercritical range) and high tempering.