Effect of compression temperature on deformation of CaO–CaS–Al2O3–MgO inclusions in pipeline steel

Plain strain deformation trials were carried out on samples of pipeline steels at 1473 K, 1673 K and 1723 respectively. The inclusions in the solid steel different temperatures semi-solid was studied. composition changed from 60.62%Al2O3–16.10%CaO–10.27%MgO–13.01%CaS before to 60.59%Al2O3–13.03%CaO–12.74%MgO–13.63%CaS, 59.69%Al2O3–7.04%CaO–11.51%MgO–21.76%CaS, 68.26%Al2O3–22.56%CaO–6.68%MgO–2.5%CaS with corresponding deforming K. While average aspect ratio increased 1.28 2.23, 1.32, 1.35, Thermodynamic calculations performed by FactSage 7.0 verified transformation CaO CaS during solidification cooling process steel. A kinetic model used calculate dynamic inclusion compression temperatures. 38.28% 50.50% For temperature below thickness hard phase soaking temperature, while hardness matrix decreased. larger difference between led a higher after deformation. steel, small soft resulted low