Method of welding nickel-aluminide

Patent metadata

Field	Value
Publication number	US-9623509-B2
Application number	US-201213346922-A
Country	US
Kind code	B2
Filing date	Jan 10, 2012
Priority date	Jan 10, 2011
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

A method for gas tungsten arc welding (GTAW) of nickel-aluminide is provided. The method includes machining a weld groove having a width from 1 to 2 mm on an outer surface, a weld groove angle with a vertical being less than 30°; and a root face being not longer than 3 mm. During welding, a measured temperature 30 cm (12″) from a weld torch and 3 mm from the weld groove edge should not exceed 200° C.; and an interpass temperature should be less than 85° C. measured at 3 mm from the weld groove edge. With exception of the root pass, all filler and cap pass layering should start from the nickel-aluminide edge, each bead should be peened; and the weld cap pass should overlap on the nickel-aluminide surface edge by at least 3 mm. The weld bead layout at the nickel-aluminide edge should be laid at torch angle less than 30°, and the weld heat input should be in the range of 17 to 23 kJ/in. The linear welding speed is greater than 8.6 cm/min and a deposition rate should be greater than 3.0 cm 3 /min.

First claim

What is claimed is:

1. A method for gas tungsten arc welding (GTAW) of nickel-aluminide to itself or other nickel-based alloys using a filler wire, comprising the steps of:
machining a weld groove having a width from 1 to 2 mm on an outer surface of the nickel-aluminide, an angle of the weld groove with a vertical being 30° or less and a root face being 3 mm or less;
during welding, measuring a temperature 30 cm (12″) from a weld torch and 3 mm from a weld groove edge, the temperature being 200° C. or less, and measuring an interpass temperature 3 mm from the weld groove edge, the interpass temperature being 85° C. or less;
starting from a nickel-aluminide edge, layering all filler and cap pass, with the exception of a root pass, peening each bead, and overlapping the weld cap pass on the nickel-aluminide surface edge by at least 3 mm; and
laying a weld bead layout at the nickel-aluminide edge at a torch angle of 30° or less, the weld heat input being from 17 to 23 kJ/in;
a linear welding speed being 8.6 cm/min or more and a deposition rate being being 3.0 cm 3 /min or more.

2. The method of claim 1 , further comprising the step of:
providing nickel-aluminide having a composition in weight %, including:
70≦Ni≦to 85%,
6≦Al≦10%,
5≦Cr≦10%,
0≦Zr≦8%,
0≦Mo≦6%, and
0.0001≦B≦0.02%.

3. The method of claim 2 , wherein said nickel-aluminide includes 0≦Zr≦1%.

4. The method of claim 3 , wherein said nickel-aluminide comprises 0≦Zr≦0.15%.

5. The method of claim 4 , wherein said nickel-aluminide comprises 0% Zr.

6. The method of claim 1 , further comprising the step of:
providing nickel-aluminide having a composition in weight %, including:
C≦0.05%;
S≦0.005%;
Cr=7.7%;
Mn≦0.1%;
Si≦0.1%;
Mo=3.0%;
Al=7.8%;
0.08≦Zr≦0.15%;
B=0.008%;
Cu≦0.3%;
P≦0.01%; and
a balance of the composition consisting of Ni.

7. The method of claim 1 , further comprising the step of:
providing a nickel-aluminide furnace roll sleeve; and
providing a nickel-based alloy furnace roll bell for welding to the nickel-aluminide furnace roll sleeve.

8. The method of claim 1 , further comprising the step of preheating the filler wire to increase the deposition rate thereof.

9. The method of claim 1 , wherein a maximum current for manual GTAW is 105 A and for automatic GTAW is 120 A.

10. The method of claim 1 , wherein the maximum bead width per pass is 9 mm.

11. The method of claim 1 , further comprising the steps of:
overlaying ductile filler wire over the edge of the nickel-aluminide material; and
machining a weld groove in the overlaid ductile filler wire.

12. The method of claim 1 , including the further steps of:
preheating the edge of the nickel-aluminide to 500° C.; and
maintaining the nickel-aluminide 3 mm from the edge at 500° C. during the GTAW process.

13. The method of claim 1 , including the further steps of:
heating the nickel-aluminide to 900° C.; and
soaking the nickel-aluminide at 900° C. for 1 hour per inch (25.4 mm) thickness thereof.

Assignees

• Lalam Sree Harsha
• Arcelormittal

Inventors

• Lalam Sree Harsha

Classifications

• B23K2103/52

  Ceramics · CPC title

• B23K2103/26

  Alloys of Nickel and Cobalt and Chromium · CPC title

• B23K2103/08

  Non-ferrous metals or alloys · CPC title

• B23K2103/10

  Aluminium or alloys thereof · CPC title

• B23K9/23 Primary

  taking account of the properties of the materials to be welded · CPC title