Nickel/iron-based braze and process for brazing
View Patent ↗Disclosed are a braze, such as a braze in the form of an amorphous, ductile brazing foil, having a composition consisting essentially of Fe a Ni rest Si b B c M d with 5 atomic percent≦a≦35 atomic percent, 1 atomic percent≦b≦15 atomic percent, 5 atomic percent<c≦15 atomic percent, 0≦d≦4 atomic percent, rest Ni and incidental impurities, wherein M is one or more of the elements Co, Cr, Mn, Nb, Mo, Ta, Cu, Ag, Pd or C, and having a liquidus temperature T L ≦1025° C. Also disclosed are apparatus containing parts joined by said braze, methods for using said braze, and methods for making said amorphous, ductile brazing foil.
1. An apparatus comprising two or more parts joined by a braze comprising:
a composition consisting essentially of:
Fe a Ni rest Si b B c M d
wherein approximately 10 atomic percent≦a≦approximately 35 atomic percent, 1 atomic percent≦b≦15 atomic percent, 5 atomic percent<c≦15 atomic percent, 0≦d≦4 atomic percent, rest Ni and incidental impurities,
wherein M is one or more of the elements Co, Cr, Mn, Nb, Mo, Ta, Cu, Ag, Pd or C; and
wherein said braze has a liquidus temperature T L ≦1025° C. and has been formed from an at least 50% amorphous, ductile brazing foil having a thickness D, where 10 μm≦D≦100 μm,
wherein the apparatus comprises a heat exchanger or a component thereof having at least one solder seam produced with said braze.
2. The apparatus in accordance with claim 1 , wherein the Si content is such that 6 atomic percent≦b≦13 atomic percent.
3. The apparatus in accordance with claim 1 , wherein the B content is such that 8 atomic percent≦c≦14 atomic percent.
4. The apparatus in accordance with claim 1 , wherein the Fe content is such that 10 atomic percent≦a≦30 atomic percent.
5. The apparatus in accordance with claim 1 , wherein the liquidus temperature T L ≦1000° C.
6. The apparatus in accordance with claim 5 , wherein the liquidus temperature T L ≦980° C.
7. The apparatus in accordance with claim 1 , wherein said thickness D is 40 μm≦D≦100 μm.
8. The apparatus in accordance with claim 1 , wherein the brazing foil has a width B, where 20 mm≦B≦200 mm.
9. The apparatus in accordance with claim 8 , wherein said width B is 40 mm≦B≦200 mm.
10. The apparatus according to claim 1 , wherein said braze is a brazing foil, and wherein said solder seam has a thickness >20 μm.
11. The apparatus in accordance with claim 1 , wherein said heat exchanger is a component of a fuel cell.
12. The apparatus in accordance with claim 1 , wherein M is one or more of the elements Co, Cr, Mn, Nb, Mo, Ta, Cu, Ag, or Pd.
13. An apparatus comprising two or more parts joined by a braze comprising:
a composition consisting essentially of:
Fe a Ni rest Si b B c M d
wherein approximately 10 atomic percent≦a≦approximately 35 atomic percent, 1 atomic percent≦b≦15 atomic percent, 5 atomic percent<c≦15 atomic percent, 0≦d≦4 atomic percent, rest Ni and incidental impurities,
wherein M is one or more of the elements Co, Cr, Mn, Nb, Mo, Ta, Cu, Ag, Pd or C; and
wherein said braze has a liquidus temperature T L ≦1025° C. and has been formed from an at least 50% amorphous, ductile brazing foil having a thickness D, where 10 μm≦D≦100 μm,
wherein said parts comprise one or more of low- or mid-alloyed steel, a stainless steel, an alloy of Co, copper, or a copper alloy, or
a precipitation-hardened Ni-based alloy.