Abstract: The continuous casting test for high-speed steel W6Mo5Ci4V2 is carried out by using 150 kg medium frequency induction electric furnace- 150 kg interim ladle and designed Φ100 mm vertical continuous caster with mold vibration frequency 1. 2 Hz and vibration amplitude ± 3 mm, casting speed 0. 4 m/min and secondary cooling water pressure 0. 2 MPa, and the thickness of ledeburite net and solidification cooling rate of the high-speed steel at different process conditions are measured. Results show that as compared with 15 kg common ingot mold casting high-speed steel W6Mo5Cr4V2, the structure of high speed steel Φ100 mm casting billet by vertical continuous casting process is dense without defects, the ledeburite net is obviously thinner, the average thickness of ledeburite net at center of casting billet is ≤16μm, and the grains markedly fine； the precipitated amount of carbide M₂C and MC obviously increases while the carbide M₆C precipitated amount decreases, and the carbides are more fine, homogeneous and dispersed; the solidification cooling rate at edge of casting billet is 3. 33 x 10⁴K/s, at r/2 is 9. 4 x 10³K/s and at center is 8. 1 x 10²K/s, its metallurgical quality is obviously higher than that of common ingot mold casting.

摘要： 采用150 kg中频感应炉-150 kg过渡钢包在设计的Φ100 mm立式连铸机以结晶器振动频率1.2 Hz和振幅±3 mm,拉速0.4 m/min,二冷水压力0.2 MPa进行高速钢W6Mo5Cr4V2连铸试验,并测定了在不同工艺条件下高速钢莱氏体网的厚度和冷却速率。结果表明,与15kg锭普通模铸高速钢W6Mo5Cr4V2相比,Φ100 mm立式连续铸造得到的高速钢铸坯低倍组织致密无缺陷,莱氏体网明显变薄,铸坯心部莱氏体网平均厚度≤16μm,晶粒明显细化;M₂C和MC型碳化物的析出量增多,M₆C型碳化物的析出量减少,碳化物更加细小、均匀和弥散;铸坯边部的冷却速率为3.33×10⁴K/s, r/2处为9.4×10³K/s,心部为8.1×10²K/s,冶金质量明显优于普通模铸。

关键词: 高速钢, W6Mo5CMV2, Φ100 mm连铸坯, 共晶碳化物, 冷却速率, 冶金质量