Nickel-based brazing foil and process for brazing

Patent metadata

Field	Value
Publication number	US-2016207130-A1
Application number	US-201615082338-A
Country	US
Kind code	A1
Filing date	Mar 28, 2016
Priority date	Oct 15, 2007
Publication date	Jul 21, 2016
Grant date	—

Abstract

An amorphous, ductile brazing foil is provided. According to one example embodiment, the composition consists essentially of Ni rest Cr a B b P c Si d with 2 atomic percent≦a≦30 atomic percent; 0.5 atomic percent≦b≦14 atomic percent; 2 atomic percent≦c≦20 atomic percent; 0 atomic percent≦d≦14 atomic percent; incidental impurities≦0.5 atomic percent; rest Ni, where c>b>c/15 and 10 atomic percent≦b+c+d≦25 atomic percent.

First claim

1 . An amorphous, ductile Ni-based brazing foil having a composition consisting essentially of
Ni rest Cr a B b P c Si d C e X f Y g wherein a, b, c, d, e, f, and g are numbers such that 16 atomic percent≦a≦30 atomic percent; 0.5 atomic percent≦b≦14 atomic percent; 2 atomic percent≦c≦20 atomic percent; 0 atomic percent≦d≦14 atomic percent; 0 atomic percent≦e≦5 atomic percent; 0 atomic percent<f≦3 atomic percent; 0 atomic percent<g≦5 atomic percent; wherein incidental impurities are present, if at all, in amounts 0.5 atomic percent; wherein rest indicates that the balance of the composition is Ni; wherein c>b>c/15; wherein 10 atomic percent b+c+d≦25 atomic percent, wherein X is one or more of the elements Mo, Nb, Ta, W and Cu; and wherein Y is one or both of the elements Fe and Co.

2 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the B content b is such that 1 atomic percent≦b≦8 atomic percent.

3 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the P content c is such that 5 atomic percent≦c≦18 atomic percent.

4 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the Si content d is such that d=0 atomic percent.

5 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the Si content d is such that 0 atomic percent<d≦14 atomic percent.

6 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the Y content g is 0 atomic percent≦g≦1 atomic percent.

7 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the brazing foil is at least 80% amorphous.

8 . The amorphous, ductile brazing foil in accordance claim 1 , wherein the foil has a thickness D of 15 μm≦D≦75 μm.

9 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the foil has a width B of 0.5 mm≦B≦300 mm.

10 . The amorphous, ductile brazing foil in accordance with claim 9 , wherein the width B is 30 mm≦B≦150 mm.

11 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 25% over a length of 200 m.

12 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 20% over a length of 100 m.

13 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 10% over a length of 5000 m.

14 . The amorphous, ductile brazing foil in accordance with claim 1 , wherein the foil varies in thickness from a mean thickness of the foil in a variation of less than 15 μm over a length of 100 m.

15 . A brazed object having a first part joined to a second part by a solder seam produced by heating the brazing foil of claim 2 .

16 . The brazed object in accordance with claim 16 , wherein both the first part and the second part are made of a stainless steel.

7 . The brazed object in accordance with claim 16 , wherein the solder seam has a thickness that is>15 μm.

18 . The brazed object n accordance with claim 16 , wherein the brazed object is a heat exchanger.

19 . The brazed object of claim 16 , wherein the heat exchanger is an exhaust gas recirculation cooler or an oil cooler.

20 . The brazed object of claim 17 , wherein the brazed object is a heat exchanger.

21 . The brazed object of claim 18 , wherein the brazed object is a heat exchanger.

22 . A process for producing an amorphous ductile brazing foil comprising:
providing a molten mass consisting essentially of Ni rest B b P c Si d C d X f Y g wherein a, b, c, d, e, f, and g are numbers such that 16 atomic percent≦a≦30 atomic percent; 0.5 atomic percent≦b≦14 atomic percent; 2 atomic percent≦c≦20 atomic percent; 0 atomic percent≦d≦14 atomic percent; 0 atomic percent≦e≦5 atomic percent; 0 atomic percent<f≦3 atomic percent; 0 atomic percent≦g≦5 atomic percent, wherein incidental impurities are present, if at all, in amounts≦0.5 atomic percent; wherein rest indicates that the balance of the molten mass is Ni; wherein c>b>c/15 and 10 atomic percent≦b+c+d≦25 atomic percent; wherein X is one or more of the elements Mo, Nb, Ta, W and Cu; and wherein Y is one or both of the elements Fe and Co, rapidly solidifying the molten mass on a moving cooling surface with a cooling speed of more than approximately 10 5 ° C./sec to produce an amorphous ductile brazing foil.

23 . A process for joining by fusion two or more parts comprising:
inserting of a brazing foil in accordance with claim 1 between two or more parts to be joined, wherein the parts to be joined have a higher melting temperature than that the brazing foil to form a solder joint; heating the solder joint to a temperature above the liquidus temperature of the brazing foil to form a heated solder joint; cooling the heated solder joint, thereby forming a brazed joint between the parts to be joined.

24 . The process in accordance with claim 3 , wherein the heating of the solder joint to a temperature above the liquidus temperature of the brazing foil is carried out in inert gas.

25 . The process in accordance with claim 23 , wherein the heating of the solder joint to a temperature above the liquidus temperature of the brazing foil is carried out in a continuous furnace.

Assignees

• Vacuumschmelze Gmbh & Co Kg

Inventors

• Hartmann Thomas
• Nuetzel Dieter

Classifications

• C22C1/11

  Making amorphous alloys · CPC title

• F02M26/29

  Constructional details of the coolers, e.g. pipes, plates, ribs, insulation or materials · CPC title

• B23K35/0233

  Sheets or foils (B23K35/0244 takes precedence) · CPC title

• C22C45/04

  with nickel or cobalt as the major constituent · CPC title

• C22F1/10

  of nickel or cobalt or alloys based thereon · CPC title