Abstract: The reduction of area and tensile strength of Φ10 mm×120 mm specimen drilled and turned from 280 mm ×380 mm cast billet of0.03Nb,0.03Nb-0.02Vand 0.05VMicroalloyed 0.75~0.78C high carbon steel have been tested  at 1300~800 ℃ by Cleeble 1500D thermal simulation machine.Results showed that the hot plasticity of V-steel in first brittle zone ≥1200'℃ and third brittle zone1000~800 ℃ was better than that of Nb-steel and Nb-V steel.It was indica- ted by scanning electron microscopy and energy spectrum analysis that Fe-Nb-C eutectic existed in cast billet of Nb- steel, and Fe-Nb eutectic existed in cast billet of Nb-V steel added V.

Key words: Nb- V- Microalloying,High Carbon Steel,Hot Workability

摘要： 用Gleeble 1500D热模拟机试验了0.03%Nb、0.03%Nb-0.02%V和0.05%V微合金化0.75%～0.78%C高碳钢280 mm×380 mm铸坯上钻取的Φ10 mm×120 mm试样在1 300～800℃的断面收缩率和抗拉强度。结果表明,第1脆性区≥1 200℃和第3脆性区1 000～800℃V-钢的热塑性优于Nb-V钢和Nb钢。扫描电镜和能谱分析表明,Nb-钢铸坯存在Fe-Nb-C共晶体,加入V的Nb-V钢铸坯存在Fe-Nb共晶体。

关键词: Nb-V-微合金化, 高碳钢 , 热加工性