渣系组元对电渣重熔核级316H不锈钢中氢含量的影响

Influence of Slag System Ingredients on Hydrogen Content in 316H Stainless Steel for Electroslag Remelting in Nuclear Power Applications

在电渣重熔的过程中,钢中气体成分(如H、O、N等)的含量受所用渣系的气体渗透率影响显著。为了探索出一种适合核电用316H不锈钢的低氢渗透率的电渣重熔用渣系,测定了5种电渣重熔渣系的氢渗透率。研究结果表明,新开发的63%CaF_(2)-30%A_(l)2O_(3)-7%MgO渣系的氢渗透率最低。同时65%CaF_(2)-30%A_(l)2O_(3)-5%MgO渣系的氢渗透率与之较为接近,并且这两种渣系的氢渗透率与钢厂电渣生产所用原渣系60%CaF_(2)-20%A_(l)2O_(3)-20%CaO的氢渗透率相比均有明显降低,分别由6.58×10^(-6) mol/(cm·min)降至1.89×10^(-6) mol/(cm·min)和2.18×10^(-6) mol/(cm·min)。熔渣的光学碱度越大,氢渗透率也越大。渣中的CaO有较大的水容性,在电渣重熔过程中容易使钢锭中的氢含量升高,渣系中MgO的添加能够显著地降低氢渗透率。在研究条件下,渣系的组元对渣系的氢渗透率的影响比光学碱度更为显著。

During the process of electric arc remelting,the content of gas components(such as H,O,N,etc.)in the steel is significantly influenced by the gas permeability of the slag system used.In order to explore a slag system with low hydrogen permeability suitable for nuclear-grade 316H stainless steel in electric arc remelting,the hydrogen permeability of five slag systems used in electric arc remelting was determined.The results showed that the newly developed 63%CaF_(2)-30%A_(l)2O_(3)-7%MgO slag system had the lowest hydrogen permeability.meanwhile the hydrogen permeability of slag system,65%CaF_(2)-30%A_(l)2O_(3)-5%MgO,was similar to that of the 63%CaF_(2)-30%A_(l)2O_(3)-7%MgO slag system,and hydrogen permeability of both slag systems exhibited a significant reduction compared to the original slag system used in the steel plant's electric arc production,declined from 6.58×10^(-6) mol/(cm·min)to 1.89×10^(-6) mol/(cm·min)and 2.18×10^(-6) mol/(cm·min)respectively.The higher the optical basicity of the slag was,the higher the hydrogen permeability was.CaO in the slag had a high affinity for water and can easily increase the hydrogen content in the steel ingot during electric arc remelting,while the addition of MgO in the slag system can significantly reduce hydrogen permeability.Under the research conditions,the influence of the slag system's constituents on its hydrogen permeability was more significant than the optical basicity.