Ferrochrome powder is mainly used to produce ferrochrome and chromium metal. Chromium iron alloy as steel additive to produce a variety of high strength, corrosion resistance, wear resistance, high temperature resistance, oxidation resistance of special steel, such as stainless steel, acid-resistant steel, heat resistant steel, ball bearing steel, spring steel, tool steel, etc. In refractories, chromite powder is used to make chrome bricks, chrome magnesia bricks and other special refractories.
The smelting of low carbon steel such as stainless steel must use low carbon ferrochrome, so the production of refined ferrochrome has been developed on a large scale. As a result of the improvement of steelmaking process, now with AOD method (see furnace refining) and other steel production, such as stainless steel, with carbon ferrochrome (mainly charge grade ferrochrome) furnace, so only in the later period to add low, micro carbon ferrochrome adjustment composition, so now the focus of ferrochrome production is refining carbon ferrochrome.
The electric furnace for smelting si-Cr alloy is similar to the electric furnace for reducing chromite. There are two smelting methods, one step and two step. One-step smelting with ferrochrome powder, silica and coke with flux. The two-step process USES carbon ferrochrome, silica and coke as raw materials for slag free smelting, smelting process is roughly similar to ferrosilicon production. Smelting power consumption per ton about 3000 ~ 4000 KWH.
Low and micro - carbon ferrochrome is also produced by heat transfer on a large scale. It is produced in two electric furnaces, one smelting silicon-chromium alloy and one melting slag, which consists of chromium ore and lime. The refining reaction is divided into two stages in two buckets: (1) slag slag furnace slag injected into a bucket, another bucket has been preliminary desilication of silicon chromium alloy into, because the slag oxidant excess amount is large, desilication is sufficient, can be obtained with silicon less than 0.8%, carbon low up to 0.02% of micro carbon ferrochrome. After the reaction of the slag in a bucket (containing about 15% Cr2O3) moved to the second bucket, the silicon and chromium alloy (containing 45% silicon) refined by the electric furnace is heated into the slag, after the reaction, the silicon and chromium alloy with preliminary desilication (containing about 25% silicon) is obtained, mixed into a bucket for further desilication, the slag containing Cr2O3 less than 2 ~ 3% can be abandoned.