1. Problems in the selection of raw materials:
(1) Higher impurity content of raw materials. The performance of ferromanganese alloy is affected by impurities, and a high content of impurities will reduce the quality of the alloy. The solution is to strengthen the screening and testing of raw materials, and select raw materials with higher purity.
(2) Uneven granularity of raw materials. Uneven granularity will lead to inconsistent dissolution speed of the alloy, affecting the alloy composition and quality of the alloy. The solution is to carry out reasonable grading and mixing of raw material particles to ensure the homogeneity of raw materials.
2. Problems in smelting operation:
(1) Inaccurate control of furnace temperature. In the smelting process, the control of furnace temperature directly affects the composition and quality of the alloy. Too high furnace temperature will lead to increased evaporation loss of the alloy, while too low furnace temperature will affect the melting degree of the alloy. The solution is to strengthen the monitoring and control of furnace temperature, and adopt the automatic control system to realise the stable control of furnace temperature.
(2) Excessive smelting time. Too long smelting time will lead to increased loss of manganese in the alloy by evaporation, reduce the manganese content of the alloy, and also increase the energy consumption of smelting. The solution is to control the smelting time and reasonably arrange the smelting time of each process to improve the smelting efficiency and alloy quality.
(3) Poor slagging effect. Poor slagging will lead to insufficient discharge of oxides in the smelting process, affecting the quality of the alloy. Manganese ferroalloy which is a good solution is to improve the slagging process, can increase the use of slagging agent, change the formula of slagging agent and add iron-carbon alloy and other measures to improve the effect of slagging.
(4) Incomplete slagging. Incomplete slagging will make the residual slag mixed in the alloy, affecting the composition uniformity and quality stability of the alloy. The solution is to use the appropriate slagging process, strengthen the operation technology when slagging, to ensure that the slag is thoroughly discharged.
3. Problems in alloy quality:
(1) Alloy composition deviation from the requirements. Alloy composition is not in line with the requirements, which will affect the use of alloy and market competitiveness. The solution is to reasonably design the ratio of raw materials, optimise the smelting process, strengthen the quality control and monitoring in the production process to ensure that the alloy composition meets the requirements.
(2) More inclusions in the alloy. More inclusions in the alloy will reduce the strength, toughness and corrosion resistance of the alloy, and even cause cracks and fractures. The solution is to strengthen the control of the smelting process to reduce the generation and residue of inclusions. At the same time, in the production process, strengthen the quality control and inspection, and regularly carry out the detection and elimination of inclusions in the alloy.
(3) The silicon in the alloy is low. Silicon is one of the important components in ferromanganese alloy, and its low content will affect the wear resistance and high temperature resistance of the alloy. The solution is to choose raw materials with high silicon content, strengthen the control and adjustment of smelting process to ensure that the silicon content in the alloy meets the requirements.
(4) The carbon and sulphur content in the alloy is on the high side. Carbon and sulphur are unavoidable impurity elements in ferromanganese alloy, and their high content will reduce the toughness and cold working performance of the alloy. The solution is to choose raw materials with lower carbon and sulphur content and strengthen the carbon and sulphur control in the smelting process to ensure that the carbon and sulphur content in the alloy is within a reasonable range.
