Brazing foil, object and method for brazing

Patent metadata

Field	Value
Publication number	US-12516402-B2
Application number	US-202217868866-A
Country	US
Kind code	B2
Filing date	Jul 20, 2022
Priority date	Jul 26, 2021
Publication date	Jan 6, 2026
Grant date	Jan 6, 2026

Abstract

A nickel-based brazing foil with a composition consisting essentially of 11 atom %<Cr≤16 atom %, 0 atom %≤Mo≤3.5 atom %, 4 atom %≤B≤5.5 atom %, 11 atom %≤Si≤16 atom %, 0 atom %≤P≤0.5 atom %, 0 atom %≤C≤0.85 atom %, 0 atom %≤Fe≤5 atom %, 0 atom %≤Co≤5 atom %, 0 atom %≤Cu≤2 atom %, 0 atom %≤V≤2 atom %, 0 atom %≤Nb≤2 atom %, incidental impurities of ≤1.0 wt. % and the rest Ni, is provided.

First claim

The invention claimed is:

1 . An object having a first part and a second part, the first part being permanently connected to the second part by a brazed seam produced using a brazing foil, the brazing foil with a composition consisting essentially of 11 atom %<Cr≤16 atom %, 0 atom %≤Mo≤3.5 atom %, 4 atom %≤B≤5.5 atom %, 11 atom %≤Si≤16 atom %, 0 atom %≤P≤0.5 atom %, 0 atom %≤C≤0.85 atom %, 0 atom %≤Fe≤5 atom %, 0 atom %≤Co≤5 atom %, 0 atom %≤Cu≤2 atom %, 0 atom %≤V≤2 atom %, 0 atom %≤Nb≤2 atom %, incidental impurities of ≤1.0 wt. %, one or more of the elements Mo, Nb, and V up to the respective maximum atom %; and at least 0.5 atom % of one or more of the elements Mo, Nb and V being present, and the rest Ni.

2 . An object according to claim 1 , wherein the first part and the second part are each made of a stainless steel that contains at least 12 wt. % chromium, and at least 0.5 wt. % molybdenum.

3 . An object according to claim 1 , wherein the object is a heat exchanger or part of a heat exchanger that comes into contact with drinking water during operation.

4 . An object according to claim 1 , wherein the object is a heat exchanger with a media-contacting surface ratio greater than 0.5 m 2 /l.

5 . An object according to claim 1 , wherein the object has a burst pressure of over 60 bar.

6 . An object according to claim 1 , wherein the object carries water during operation and, after an operating period of more than 4 weeks in the drinking water and an exposure time of 168 hours at 25° C. in a volume of drinking water and with a drinking-water-contacting surface area ratio of 1.25 m 2 /l, emits a total Ni concentration of less than 200 μg/l into the drinking water.

7 . An object according to claim 1 , wherein the object carries water during operation and, after an operating period of more than 4 weeks in the drinking water and an exposure time of 168 hours at 25° C. in a volume of drinking water and with a drinking-water-contacting surface area ratio of 1.25 m 2 /l, emits a total concentration of Ni plus Cu plus Fe of less than 400 μg/l into the drinking water.

Assignees

• Vacuumschmelze Gmbh & Co Kg

Inventors

• Hartmann Thomas

Classifications

• B23K35/304

  with Cr as the next major constituent · CPC title

• B23K1/0012

  Brazing of heat exchangers · CPC title

• F28D9/005

  the plates having openings therein for both heat-exchange media · CPC title

• C22C2200/02

  Amorphous · CPC title

• B23K35/0233

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