Electroslag remelting slag system and electroslag remelting 40CrNiMoA low-hydrogen control method

Abstract

The invention discloses an electroslag remelting slag system and an electroslag remelting 40CrNiMoA low-hydrogen control method. The slag system adopted in electroslag remelting comprises components including, by weight percent, 20%-30% of Al2O3, 5%-8% of SiO2, 3%-5% of MgO and the balance CaF2. The alkalinity of the electroslag remelting slag system is 0.7-0.9. Slag materials, electrodes and argon are subjected to drying treatment, and the source of hydrogen in the electroslag process is greatly reduced. Aluminum powder needs to be evenly added in the electroslag remelting process, and the aluminum powder adding speed is 1.5-3 g / min. According to the low-hydrogen control method, the hydrogen reduction effect is extremely good, operation is simple, and energy consumption and cost are low.The hydrogen content of the prepared remelting 40CrNiMoA alloy is low to 3 ppm, and the surface is free of white spots. The method is easy to control and low in cost. The properties such as strength,tenacity, abrasion resistance and corrosion resistance are shown excellently.

Description

Technical field

[0001] The invention relates to the technical field of electrometallurgy, in particular to an electroslag remelting slag system and a 40CrNiMoA low hydrogen control method for electroslag remelting. Background technique

[0002] Electroslag remelting metallurgy technology, to obtain high-quality steel ingots is to purify metals under the conditions of sufficient reaction between steel and slag, and solidify and crystallize in a water-cooled crystallizer under the thermal protection of high-temperature molten slag. Due to the slag skin on the surface of the steel ingot, not only a smooth and good surface of the ingot is obtained, but also the poor thermal conductivity of the slag skin promotes the axial crystallization of the steel ingot and weakens the development of the radial solidified crystal structure. In addition, steel ingots with dense structure, segregation and uniform composition can be obtained. However, in the electroslag remelting process, the opposi...

Examples

Embodiment 1

[0027] 1) Prepare electroslag remelting slag system, and its components are CaF in parts by weight 2 70 servings, Al 2 O 3 20 parts, SiO 2 6 parts, 4 parts of MgO, the alkalinity of the slag system B=0.84, weight 130kg;

[0028] 2) Bake the slag described in step 1) at 200°C for 4 hours, then at 800°C for 4 hours, take it out and use it immediately;

[0029] 3) Choose 40CrNiMoA electrode blank ∮400mm, clean the folds, slag inclusions, rust, etc. on the surface of the electrode blank, and the surface is sanded and bright, and the electrode blank is baked in a weak oxidizing atmosphere at 200°C for 3 hours; Weak oxidizing atmosphere includes CO, CO 2 And O 2 The mixed gas, the CO and CO 2 The total concentration of 30%, the O 2 The concentration is 5%.

[0030] 4) After assembling the electroslag remelting furnace, add step 2) the baked electroslag remelting slag to the crystallizer with an average diameter of ∮600mm. Adjust the voltage to 63V and the current to 12000A. Electroslag...

Embodiment 2

[0032] 1) Prepare electroslag remelting slag system, and its components are CaF in parts by weight 2 70 servings, Al 2 O 3 20 parts, SiO 2 6 parts, 4 parts of MgO, the alkalinity of the slag system B=0.84, weight 130kg;

[0033] 2) Bake the slag described in step 1) at 200°C for 4 hours, then at 800°C for 3 hours, take it out and use it immediately;

[0034] 3) Choose 40CrNiMoA electrode blank ∮400mm, clean the folds, slag inclusions, rust, etc. on the surface of the electrode blank, and the surface is sanded and bright, and the electrode blank is baked in a weak oxidizing atmosphere at 200°C for 3 hours; Weak oxidizing atmosphere includes CO, CO 2 And O 2 The mixed gas, the CO and CO 2 The total concentration is 35%, the O 2 The concentration is 8%.

[0035] 4) After assembling the electroslag remelting furnace, add step 2) the baked electroslag remelting slag to the crystallizer with an average diameter of ∮600mm. Adjust the voltage to 63V and the current to 12000A. Electroslag...

Embodiment 3

[0037] 1) Prepare electroslag remelting slag system, and its components are CaF in parts by weight 2 60 servings, Al 2 O 3 30 parts, SiO 2 5 parts, 5 parts of MgO, the alkalinity of the slag system B=0.9, weight 130kg

[0038] 2) Bake the slag described in step 1) at 240°C for 4 hours, then at 900°C for 3 hours, and take it out for immediate use;

[0039] 3) Choose 40CrNiMoA electrode blank ∮400mm, clean the folds, slag inclusions, rust, etc. on the surface of the electrode blank, and the surface is sanded and bright, and the electrode blank is baked in a weak oxidizing atmosphere at 200°C for 3 hours; Weak oxidizing atmosphere includes CO, CO 2 And O 2 The mixed gas, the CO and CO 2 The total concentration is 40%, the O 2 The concentration is 8%.

[0040] 4) After assembling the electroslag remelting furnace, add step 2) the baked electroslag remelting slag to the crystallizer with an average diameter of ∮600mm. Adjust the voltage to 63V and the current to 12000A. Electroslag re...

Technical field

[0001] The invention relates to the technical field of electrometallurgy, in particular to an electroslag remelting slag system and a 40CrNiMoA low hydrogen control method for electroslag remelting. Background technique

[0002] Electroslag remelting metallurgy technology, to obtain high-quality steel ingots is to purify metals under the conditions of sufficient reaction between steel and slag, and solidify and crystallize in a water-cooled crystallizer under the thermal protection of high-temperature molten slag. Due to the slag skin on the surface of the steel ingot, not only a smooth and good surface of the ingot is obtained, but also the poor thermal conductivity of the slag skin promotes the axial crystallization of the steel ingot and weakens the development of the radial solidified crystal structure. In addition, steel ingots with dense structure, segregation and uniform composition can be obtained. However, in the electroslag remelting process, the opposi...

Examples

Embodiment 1

[0027] 1) Prepare electroslag remelting slag system, and its components are CaF in parts by weight 2 70 servings, Al 2 O 3 20 parts, SiO 2 6 parts, 4 parts of MgO, the alkalinity of the slag system B=0.84, weight 130kg;

[0028] 2) Bake the slag described in step 1) at 200°C for 4 hours, then at 800°C for 4 hours, take it out and use it immediately;

[0029] 3) Choose 40CrNiMoA electrode blank ∮400mm, clean the folds, slag inclusions, rust, etc. on the surface of the electrode blank, and the surface is sanded and bright, and the electrode blank is baked in a weak oxidizing atmosphere at 200°C for 3 hours; Weak oxidizing atmosphere includes CO, CO 2 And O 2 The mixed gas, the CO and CO 2 The total concentration of 30%, the O 2 The concentration is 5%.

[0030] 4) After assembling the electroslag remelting furnace, add step 2) the baked electroslag remelting slag to the crystallizer with an average diameter of ∮600mm. Adjust the voltage to 63V and the current to 12000A. Electroslag...

Embodiment 2

[0032] 1) Prepare electroslag remelting slag system, and its components are CaF in parts by weight 2 70 servings, Al 2 O 3 20 parts, SiO 2 6 parts, 4 parts of MgO, the alkalinity of the slag system B=0.84, weight 130kg;

[0033] 2) Bake the slag described in step 1) at 200°C for 4 hours, then at 800°C for 3 hours, take it out and use it immediately;

[0034] 3) Choose 40CrNiMoA electrode blank ∮400mm, clean the folds, slag inclusions, rust, etc. on the surface of the electrode blank, and the surface is sanded and bright, and the electrode blank is baked in a weak oxidizing atmosphere at 200°C for 3 hours; Weak oxidizing atmosphere includes CO, CO 2 And O 2 The mixed gas, the CO and CO 2 The total concentration is 35%, the O 2 The concentration is 8%.

[0035] 4) After assembling the electroslag remelting furnace, add step 2) the baked electroslag remelting slag to the crystallizer with an average diameter of ∮600mm. Adjust the voltage to 63V and the current to 12000A. Electroslag...

Embodiment 3

[0037] 1) Prepare electroslag remelting slag system, and its components are CaF in parts by weight 2 60 servings, Al 2 O 3 30 parts, SiO 2 5 parts, 5 parts of MgO, the alkalinity of the slag system B=0.9, weight 130kg

[0038] 2) Bake the slag described in step 1) at 240°C for 4 hours, then at 900°C for 3 hours, and take it out for immediate use;

[0039] 3) Choose 40CrNiMoA electrode blank ∮400mm, clean the folds, slag inclusions, rust, etc. on the surface of the electrode blank, and the surface is sanded and bright, and the electrode blank is baked in a weak oxidizing atmosphere at 200°C for 3 hours; Weak oxidizing atmosphere includes CO, CO 2 And O 2 The mixed gas, the CO and CO 2 The total concentration is 40%, the O 2 The concentration is 8%.

[0040] 4) After assembling the electroslag remelting furnace, add step 2) the baked electroslag remelting slag to the crystallizer with an average diameter of ∮600mm. Adjust the voltage to 63V and the current to 12000A. Electroslag re...

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