Specific Effects of Microalloying Elements on the Development of the Strength Properties of Low-Alloyed Chromium-Molybdenum Pipe Steels

摘要

Samples for investigation were taken from seamless hot-worked high-strength tubes for oil-and-gas pipelines (yield strength 760÷860 MPa) designed for operation in sour environments and manufactured from low-alloyed chromium-molybdenum steels. In developing the chemical composition of an experimental steel grade, Thermo-Calc-3.01 dedicated software is used for preliminary assessment of the effect of alloying elements on the type of forming carbide phases. Laboratory tests allowed recommendations to be given with regard to experimental steel grade heat treatment conditions ensuring the required complex of strength properties and resistance to sulfide stress cracking.