What are the control points of nickel and cobalt elements in the smelting of medium frequency induction furnace?

Nickel and cobalt are elements with similar physical and chemical properties. They are alloy elements with very low burning loss and easy to control. The control points are as follows.

(1) Prevent the formation of nickel and cobalt low melting point sulfides

When smelting varieties with high nickel and cobalt content, the sulfur content of the ingredients should be low, and the Mn:S ratio should be high, so as to avoid the formation of low melting point sulfides in the steel and reduce the thermoplasticity of the steel.

(2) Controlling the hydrogen content of molten steel

When using electrolytic nickel, high temperature annealing should be performed to reduce the hydrogen content and reduce the amount of hydrogen brought into the molten steel.

(3) Save resources and reduce costs

Nickel and cobalt are important scarce resources, and the ingredients should be calculated carefully. On the premise of not affecting the process performance and service performance, the ingredients should be made according to the middle and lower limits.

(4) The addition form and recovery rate of nickel and cobalt

Nickel and cobalt are used in the form of pure metal, usually put into crucible with the charge, and add molten steel during the refining period when adding a small amount.

Nickel and cobalt are chemically stable elements, the smelting recovery rate is 98 percent 100, and the return material is 94 percent 98 percent when smelting.