20CrNi2Mo钢中的Al含量控制

Controlling of Aluminum Content in 20CrNi2Mo Steel

本文研究了20Cr Ni2Mo齿轮钢在EBT初炼—LF精炼—VD（真空脱气）—VC（真空浇注）工艺条件下,Al含量对其奥氏体晶粒度、渗碳层硬度和力学性能的影响。结果表明,VD处理后按吨钢0.2 kg喂入铝线时,钢水Al的收得率较高,铝含量稳定在0.01%~0.02%,N/Al比值小于或者接近0.52,20Cr Ni2Mo钢奥氏体晶粒度得到显著细化,同时晶粒细化也使该钢渗碳层的组织和性能得到了改善。

Under the process condition of EBT primary smelting—LF refining—VD—VC, the influences of alumi-num content in 20CrNi2Mo pinion steel on the austenite grain size of steel itself, the hardness of carburized layer and the mechanical property have been studied.It turned out that after VD process, the yield of Al content for molten steel was high by feeding 0.2 kg aluminum wire per ton of steel;when the aluminum content was stable in range of 0.01%~0.02%, the N/Al ratio was less than or close to 0.52; the austenite grain size of 20CrNi2Mo steel refined significantly, so as to improve the microstructure and property of carburized layer.