Aluminum alloy fin material for heat exchangers, and method of producing the same

Patent metadata

Field	Value
Publication number	US-2016116236-A1
Application number	US-201614987387-A
Country	US
Kind code	A1
Filing date	Jan 4, 2016
Priority date	Jul 5, 2013
Publication date	Apr 28, 2016
Grant date	—

Abstract

An aluminum alloy fin material for heat exchangers, containing 0.5 to 1.5 mass % of Si; more than 1.0 mass % but not more than 2.0 mass % of Fe; 0.4 to 1.0 mass % of Mn; and 0.4 to 1.0 mass % of Zn, with the balance being Al and unavoidable impurities, wherein a metallographic microstructure before braze-heating is such that a density of second phase particles having a circle-equivalent diameter of less than 0.1 μm is less than 1×10 7 particles/mm 2 , and that a density of second phase particles having a circle-equivalent diameter of 0.1 μm or more is 1×10 5 particles/mm 2 or more, wherein a tensile strength before braze-heating, TS B (N/mm 2 ), a tensile strength after braze-heating, TS A (N/mm 2 ), and a fin sheet thickness, t (μm), satisfy: 0.4 ≦(TS B −TS A )/t≦ 2.1 , and wherein the sheet thickness is 150 μm or less; and a method of producing the same.

First claim

1 . An aluminum alloy fin material for heat exchangers, comprising 0.5 to 1.5 mass % of Si; more than 1.0 mass % but not more than 2.0 mass % of Fe; 0.4 to 1.0 mass % of Mn; and 0.4 to 1.0 mass % of Zn, with the balance being Al and unavoidable impurities,
wherein a metallographic microstructure before braze-heating is such that a density of second phase particles having a circle-equivalent diameter of less than 0.1 μm is less than 1×10 7 particles/mm 2 , and that a density of second phase particles having a circle-equivalent diameter of 0.1 μm or more is 1×10 5 particles/mm 2 or more, wherein a tensile strength before braze-heating, TS B (N/mm 2 ), a tensile strength after braze-heating, TS A (N/mm 2 ), and a sheet thickness of the fin material, t (μm), satisfy a relationship: 0.4≦(TS B −TS A )/t≦2.1, and wherein the sheet thickness is 150 μm or less.

2 . A method of producing an aluminum alloy fin material for heat exchangers, comprising:
casting an aluminum alloy raw material comprising: 0.5 to 1.5 mass % of Si; more than 1.0 mass % but not more than 2.0 mass % of Fe; 0.4 to 1.0 mass % of Mn; and 0.4 to 1.0 mass % of Zn, with the balance being Al and unavoidable impurities, by a twin roll-type continuous casting and rolling method; at least one intermediate annealing, in which a first annealing of the intermediate annealing is carried out in two stages at different retention temperatures, a retention temperature of a second stage is higher than a retention temperature of a first stage, the retention temperature of the first stage is 300° C. to 450° C., the retention temperature of the second stage is 430° C. to 580° C.; and final cold-rolling at a rolling reduction ratio of 20% to 60%, after performing the intermediate annealing; wherein a metallographic microstructure before braze-heating is such that a density of second phase particles having a circle-equivalent diameter of less than 0.1 μm is less than 1×10 7 particles/mm 2 , and that a density of second phase particles having a circle-equivalent diameter of 0.1 μm or more is 1×10 5 particles/mm 2 or more, wherein a tensile strength before braze-heating, TS B (N/mm 2 ), a tensile strength after braze-heating, TS A (N/mm 2 ), and a sheet thickness of the fin material, t (μm), satisfy a relationship: 0.4≦(TS B −TS A )/t≦2.1, and wherein the sheet thickness is 150 μm or less.

3 . The method of producing an aluminum alloy fin material for heat exchangers according to claim 2 , wherein a cooling speed from the time point of completion of a retention for annealing of the second stage to 250° C. is set to 50° C./hour or less.

Assignees

• Uacj Corp

Inventors

• Fukumoto Atsushi
• Mochizuki Junichi
• Niikura Akio

Classifications

• C22F1/00

  Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working (apparatus for mechanical working of metal B21, B23, B24) · CPC title

• B22D11/0622

  formed by two casting wheels · CPC title

• B22D11/003

  Aluminium alloys · CPC title

• C22F1/04

  of aluminium or alloys based thereon · CPC title

• C22F1/043

  of alloys with silicon as the next major constituent · CPC title