Degassing of martensitic stainless steel before remelting beneath a layer of slag
View Patent ↗The invention relates to a method of fabricating a stainless martensitic steel, comprising a step of electroslag remelting of an ingot of said steel then a step of cooling said ingot. Before the electroslag remelting step, the ingot undergoes vacuum degassing for a time that is sufficient to obtain a hydrogen content in the ingot of less than 3 ppm.
1. A method of fabricating a stainless martensitic steel, the method comprising:
vacuum degassing an ingot comprising a steel in a liquid metal state for a time sufficient to obtain a hydrogen content in the ingot of less than 3 ppm; then
electroslag remelting the ingot; and then
cooling the ingot.
2. The method of claim 1 , further comprising, prior to the remelting:
dehydrating the slag.
3. The method of claim 2 , wherein the vacuum degassing is carried out for a time that is sufficient to obtain a hydrogen content in the ingot after the electroslag remelting of less than 3 ppm.
4. The method of claim 2 , further comprising, prior to the degassing:
refining the ingot in an ambient atmosphere.
5. The method of claim 2 , wherein a carbon content of the steel is less than 0.49 wt %, based on a total weight of the steel.
6. The method of claim 1 , wherein the vacuum degassing is carried out for a time that is sufficient to obtain a hydrogen content in the ingot after the electroslag remelting of less than 3 ppm.
7. The method of claim 6 , further comprising, prior to the degassing:
refining the ingot in an ambient atmosphere.
8. The method of claim 6 , wherein a carbon content of the steel is less than 0.49 wt %, based on a total weight of the steel.
9. The method of claim 1 , further comprising, prior to the degassing;
refining the ingot in an ambient atmosphere.
10. The method of claim 9 , wherein a carbon content of the steel is less than 0.49 wt %, based on a total weight of the steel.
11. The method of claim 1 , wherein a carbon content of the steel is less than the carbon content below which the steel is hypoeutectoid.
12. The method of claim 11 , wherein a carbon content of the steel is less than 0.49 wt %, based on a total weight of the steel.