Method for brazing together planar and nonplanar metal members

Patent · Tue Jan 01 04:00:00 EST 1985

OSTI ID:865381

Hammersand, Fred G ^[1]; Witkowski, Anthony J ^[2]

---

1. East Petersburg, PA
2. Lancaster, PA

The invention relates to a method and apparatus for brazing two metal members together, at least one of which is nonplanar, in a brazing furnace using a substantially pure brazing material. The method comprises the steps of utilizing a brazing fixture to hold the two metal members in tangential relation to one another along a portion of each member so that a cavity is formed adjacent to the contacting portions. A braze material is then positioned within the cavity. The braze fixture, the metal members, and the braze material are then placed in a brazing furnace. A heat shield is then placed over the braze fixture, the metal members, and the braze material to shield the braze material from direct furnace radiation. The furnace temperature is linearly increased at a rate of about 180.degree. C. per hour until a temperature of 350.degree. C. is achieved. Heat is transferred by conduction from the metal members to the braze material to cause the braze material to melt. Some material from the metal members slowly diffuses into the braze material forming a braze joint. The furnace is rapidly cooled to room temperature using nitrogen gas. The brazed assemblies made according to this method are superior to assemblies formed by heliarc welding.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• DOE Contract Number: W-7405-ENG-48
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 4506822
• OSTI ID: 865381
• Country of Publication: United States
• Language: English

Related Subjects

/228/
180
350
according
achieved
adjacent
apparatus
assemblies
braze
braze fixture
braze material
brazed
brazing
brazing material
cavity
comprises
conduction
contacting
cooled
degree
diffuses
direct
fixture
formed
formed adjacent
forming
furnace
furnace temperature
gas
heat
heat shield
heliarc
hold
hour
increased
joint
linearly
material
material forming
melt
metal
method
method comprise
method comprises
nitrogen
nitrogen gas
nonplanar
placed
planar
planar metal
portion
portions
positioned
pure
radiation
rapidly
rapidly cool
rapidly cooled
rate
relates
relation
shield
slowly
steps
substantially
substantially pure
superior
tangential
tangential relation
temperature
transferred
utilizing
welding