Effect of titanium microalloying on microstructure and mechanical properties of vanadium microalloyed steels for hot forging

• 作者: Fan Zhao Guo-ning He Ya-zheng Liu Zhi-hao Zhang Jian-xin Xie
• 来源期刊: 钢铁研究学报（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: ORIGINAL PAPERS
• 页码范围: 295-306
• 页数: 12页
• 语种: 英文

摘要

Effect of titanium microalloying on the microstructure and mechanical properties of vanadium microalloyed steels for hot forging was studied.Titanium microalloying improves the mechanical properties mainly through refining the austenite grains.When the heating temperature is in the range of 1050-1300℃,the austenite grain diameter is decreased from 77-133 to 26-68 pm by titanium microalloying.With the decrease in austenite grain diameter,the final microstructure is refined significantly,and the high misorientation boundaries are increased.After the steel is heated at 1200℃(the common hot forging temperature)and cooled slowly,titanium microalloying decreases the yield strength from 548.4 to 519.4 MPa,and the tensile strength decreases from 842.7 to 808.7 MPa.However,the elongation increases from 19.0％to 21.4％,and the impact energy increases from 9.8 to 38.2 J.V-Ti steel has a better combination of strength,plasticity and toughness than V steel.In addition,the nucleation of intragranular ferrite idiomorphs is promoted by titanium microal-loying,which may have a beneficial effect on the property of steels with coarse microstructure caused by the critical deformation in hot die forging.