The Evolution Analysis and Removal of Oxide Inclusion in Tire Cord Steel XLX72 A

Aiming at the problem of inclusions evolution control and removal of fine wire cord steel of <inline-formula><alternatives><math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mi>ϕ</mi></math><graphic specific-use="big" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="alternativeImage/4B0E65C6-4E49-4976-897D-588FF4CCB241-M002.jpg"><?fx-imagestate width="2.03200006" height="2.87866688"?></graphic><graphic specific-use="small" xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="alternativeImage/4B0E65C6-4E49-4976-897D-588FF4CCB241-M002c.jpg"><?fx-imagestate width="2.03200006" height="2.87866688"?></graphic></alternatives></inline-formula>0.175 mm and below specifications， the transition control and removal of inclusions in cord steel were studied by using the technology of Si-Mn deoxidation， refining top slag with basicity of 0.7-1.0 and soft blowing for more than 30 min.The test results show that the number of inclusions in LF refining increases continuously， and decreases rapidly in soft blowing stage， and decreases to two to three inclusions per square millimeter when the soft blowing time reaches 30 min， and increases slightly when the soft blowing continues. In the process of LF refining and soft blowing， the nitrogen content in the steel increased， the total oxygen content decreased，and the nitrogen content in the steel is 0.003 4%-0.003 8%， the total oxygen is 0.001 2%-0.001 4% before continuous casting. Finally， the molten steel is obtained that the number of inclusions per square millimeter does not exceed 3， oxide inclusion size of molten steel ＜10 µm during continuous casting， and also no titanium nitride （TiN） inclusions and pure Al₂O₃ inclusions or high Al₂O₃ content inclusions basically， fully meet the user's requirements.