Temporary corrosion protection layer

Patent metadata

Field	Value
Publication number	US-11261514-B2
Application number	US-201716326780-A
Country	US
Kind code	B2
Filing date	Sep 22, 2017
Priority date	Sep 30, 2016
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A method for producing a component made of a steel product coated with an Al—Si protective coating, includes:
providing a substrate consisting of a steel produced coated with an Al—Si protective coating, heating the substrate to a temperature T 1 such that the Al—Si protective coating is only partially pre-alloyed with Fe of the steel product, cooling the pre-alloyed substrate to room temperature, applying a corrosion protection oil to the surface of the pre-alloyed substrate, wherein the oil consists of a composition containing fatty acid ester, transporting the pre-alloyed substrate to which the oil has been applied, heating the pre-alloyed substrate to which the oil has been applied to a temperature T 2 such that the Al—Si protective coating is fully alloyed with Fe of the steel product and the oil is removed without leaving residue, and shaping the re-heated substrate to form the component.

First claim

The invention claimed is:

1. Method for producing a component made of a steel product coated with an Al—Si protective coating, comprising:
providing a substrate consisting of a steel product coated with an Al—Si protective coating,
heating the substrate to a temperature T 1 such that the Al—Si protective coating is only partially pre-alloyed with Fe of the steel product,
cooling the pre-alloyed substrate to room temperature,
applying a corrosion protection oil to the surface of the pre-alloyed substrate, wherein the corrosion protection oil contains fatty acid esters,
transporting the pre-alloyed substrate to which the corrosion protection oil has been applied,
heating the pre-alloyed substrate to which the corrosion protection oil has been applied to a temperature T 2 , wherein the corrosion protection oil is not removed from the substrate by cleaning the pre-alloyed substrate to which the corrosion protection oil has been applied before it is heated to T 2 and the heating is carried out to T 2 such that the Al—Si protective coating is fully alloyed with Fe of the steel product and the corrosion protection oil is removed without leaving residue, and
shaping the re-heated substrate to form the component.

2. Method according to claim 1 , wherein the heating to T 2 takes place under a protective atmosphere.

3. Method according to claim 1 , wherein the composition contains at least 98% by weight of the fatty acid esters.

4. Method according to claim 1 , wherein the fatty acid esters is a C8-C16 compound.

5. Method according to claim 1 , wherein the composition has a sulfur content in the range of 0.1-2% by weight.

6. Method according to claim 1 , wherein the composition has a saponification number in the range of 150-265 mg KOH/g.

7. Method according to one of the preceding claim 1 , wherein the corrosion protection oil is applied to the substrate in a quantity of 0.5 to 2 g/m2.

8. Method according to claim 1 , wherein the temperature T 2 corresponds to a temperature range of 850° C. to 1000° C.

9. Method according to claim 1 , wherein the temperature T 1 corresponds to a temperature range of 550° to 780° C.

10. Method according to claim 1 , wherein the heating of the pre-alloyed substrate to which the corrosion protection oil has been applied to the temperature T 2 comprises:
heating the substrate to the temperature range T 2 of 850° C. to 1000° C.,
holding the substrate in the temperature range T 2 , and
cooling the substrate to a temperature range T 3 of 550° C. to 750° C.

11. Method according to claim 8 , wherein the temperature T 2 corresponds to a temperature range of 880° C. to 930° C.

12. Method according to 8, wherein the temperature T 1 corresponds to a temperature range of 600° to 700° C.

13. Method according to claim 10 , wherein the temperature T 2 is a temperature range of 880° C. to 930° C. and/or the temperature range T 3 is a temperature range of 600° C. to 700° C.

14. Method according to claim 10 , wherein the heating to T 2 is 60 to 210 s.

15. Method according to claim 10 , wherein the holding in the temperature range T 2 is 30 to 600 s.

16. Method according to claim 10 , wherein the cooling after the pre-alloying takes place occurs with a cooling rate in the range of 2 to 25 K/s.

17. Method according to claim 14 , wherein the heating to T 2 is 90 to 180 s.

18. Method according to claim 15 , wherein the holding in the temperature range T 2 is 30 to 120 s.

19. Method according to claim 16 , wherein the cooling after the pre-alloying takes place occurs with a cooling rate in the range of 8 to 20 K/s.

Assignees

• Thyssenkrupp Steel Europe Ag
• Thyssenkrupp Ag

Inventors

• Banik Janko
• Kuhn Patrick
• Ruthenberg Manuela
• Schrooten Axel
• Sikora Sascha

Classifications

• C23C2/29

  Cooling or quenching · CPC title

• C23C2/28

  Thermal after-treatment, e.g. treatment in oil bath · CPC title

• C23C2/261

  in a gas atmosphere, e.g. inert or reducing atmosphere · CPC title

• C23C2/12 Primary

  Aluminium or alloys based thereon · CPC title

• C23F11/10

  using organic inhibitors · CPC title