Powder and a HIP:ed object and the manufacture thereof
The present disclosure relates to a powder of an austenitic alloy and a HIP:ed object manufactured thereof and a process for the manufacturing the HIP:ed object and its use in corrosive environments.
1. A powder, comprising an austenitic alloy having the following composition in weight %:
C less than or equal to 0.03;
Si 0.1 to 0.5;
Mn 0.1 to 2.0;
P less than or equal to 0.04;
S less than or equal to 0.05;
Cr 26.7 to 28;
Ni 35 to 36;
Mo 6.1 to 6.7;
N 0.32 to 0.60;
Cu less than or equal to 0.4;
balance Fe and unavoidable impurities.
2. The powder according to claim 1 , wherein the content of Si is between 0.1 to 0.3 weight %.
3. The powder according to claim 1 , wherein the content of Mn is from 0.1 to 1.1 weight.
4. The powder according to claim 1 , wherein the content of Ni is from 35.3 to 36 weight %.
5. The powder according to claim 1 , wherein the content of Mo is from 6.4 to 6.6 weight %.
6. The powder according to claim 1 , wherein the content of N is of from 0.35 to 0.60 weight %.
7. The powder according to claim 1 , wherein said powder comprises less than or equal to 200 ppm O.
8. The powder according to claim 1 , wherein the content of Cr is from 26.7 to 27.8 weight %.
9. The powder according to claim 1 , wherein the content of N is of from 0.32 to 0.38 weight %.
10. The powder according to claim 1 , comprising an austenitic alloy having the following composition in weight %:
C less than or equal to 0.03;
Si 0.1 to 0.3;
Mn 0.1 to 0.5;
P less than or equal to 0.04;
S less than or equal to 0.05;
Cr 26.7 to 27.8;
Ni 35.3 to 36;
Mo 6.4 to 6.7;
N 0.35 to 0.60;
Cu less than or equal to 0.4;
O less than or equal to 200 ppm;
balance Fe and unavoidable impurities.
11. A method of manufacturing a HIP:ed object wherein the HIP:ed object is a tube, the method comprising the steps of:
a) providing a form defining a shape of a billet or a hollow or a bar;
b) providing a powder as defined in claim 10 ;
c) filling at least a portion of said form with said powder;
d) subjecting said form to hot isostatic pressing at a temperature, at an isostatic pressure, and for a predetermined time so that particles of the powder bond metallurgically to each other; and
e) hot working the obtained billet, hollow or bar.
12. A method of manufacturing a HIP:ed object wherein the HIP:ed object is a tube, the method comprising the steps of:
a) providing a form defining a shape of a billet or a hollow or a bar;
b) providing a powder as defined in claim 1 ;
c) filling at least a portion of said form with said powder;
d) subjecting said form to hot isostatic pressing at a temperature, at an isostatic pressure, and for a predetermined time so that particles of the powder bond metallurgically to each other; and
e) hot working the obtained billet, hollow or bar.
13. The method according to claim 12 , wherein the hot working process is extrusion.
14. The method according to claim 12 , wherein the method comprises a cold working step which is performed after the hot working step.
15. The method according to claim 14 , wherein the method optionally comprises a heat treatment step which is performed either after the hot working step or after the cold working step.
16. The method according to claim 15 , wherein the heat treatment process is solution annealing.
17. A HIP:ed object, comprising an austenitic alloy having the following composition in weight %:
C less than or equal to 0.03;
Si 0.1 to 0.5;
Mn 0.1 to 2.0;
P less than or equal to 0.01;
S less than or equal to 0.05;
Cr 26.7 to 28;
Ni 35 to 36;
Mo 6.1 to 6.7;
N 0.32 to 0.60;
Cu less than or equal to 0.4;
balance Fe and unavoidable impurities.
18. The HIP:ed object according to claim 17 , wherein the content of Si is between 0.1 to 0.3 weight %.
19. The HIP:ed object according to claim 17 , wherein the content of Mn 0.1 to 1.1 weight %.
20. The HIP:ed object according to claim 17 , wherein the content of Ni is from 35.3 to 36 weight %.
21. The HIP:ed object according to claim 17 , wherein the content of Mo is from 6.4 to 6.6 weight %.
22. The HIP:ed object according to claim 17 , wherein the content of N is of from 0.35 to 0.60 weight %.
23. The HIP:ed object according to claim 17 , wherein said object comprises less than or equal to 200 ppm O.
24. The HIP:ed object according to claim 17 , wherein the HIP:ed object is a tube.
25. A welded tube, comprising two or more tubes according to claim 24 , wherein the two or more tubes are joined by welding.
26. An umbilical, comprising a plurality of tubes according to claim 24 .
27. A HIP:ed object according to claim 17 , comprising an austenitic alloy having the following composition in weight %:
C less than or equal to 0.03;
Si 0.1 to 0.3;
Mn 0.1 to 0.5;
P less than or equal to 0.04;
S less than or equal to 0.05;
Cr 26.7 to 27.8;
Ni 35.3 to 36;
Mo 6.4 to 6.7;
N 0.35 to 0.60;
Cu less than or equal to 0.4;
O less than or equal to 200 ppm;
balance Fe and unavoidable impurities.
28. A method of manufacturing a HIP:ed object according to claim 17 , comprising the steps of:
a) providing a form defining at least a portion of the shape of said object;
b) providing a powder comprising an austenitic alloy having the following composition in weight %:
C less than or equal to 0.03;
Si 0.1 to 0.5;
Mn 0.1 to 2.0;
P less than or equal to 0.04;
S less than or equal to 0.05;
Cr 26.7 to 28;
Ni 35 to 36;
Mo 6.1 to 6.7;
N 0.32 to 0.60;
Cu less than or equal to 0.4;
balance Fe and unavoidable impurities;
c) filling at least a portion of said form with said powder;
d) subjecting said form to hot isostatic pressing at a temperature, at an isostatic pressure, and for a time so that particles of the powder bond metallurgically to each other.
29. The method according to claim 28 , wherein the obtained HIP:ed object is heat treated.
30. The method according to claim 28 , wherein the obtained HIP:ed object is hot worked.