Ni alloys brazing applications

Date 10-21-2004 07:03

Hi!
I need information about furnace brazing applications of Ni alloys (Inconel and Hastelloys) in Marine Gas Turbines. I would like to know what are the most used furnace atmospheres (vacuum, hidrogen...), the most used filler metals (silver base, nickel base...) and the main precautions that you must consider on brazed joints (embrittlement by sulfur and low-melting metals, cleaning prior to brazing, stress corrosion cracking, etc.)
I suppose that the alloy physical metallurgy (solid solution or precipitation hardened alloy) will be very important when you must choose the suitable brazing procedure.
I hope that this details help you.
Thank you in advance for your help.

By Bob Peaslee (*)

Date 10-28-2004 20:06

You have asked a few questions bit it will take a book of answers!
1. Vacuum is the best and most used atmosphere. Pure dry hydrogen can also be used
2. The Nickel base brazing filler metals should be used for brazing the Inconel and Hastalloy base metals. For some low temprature applications the silver, gold and copper filler meals can be used
3. A good source of brazing info is the AWS Brazing Handbook available from Global engineering Documents at 800-854-7179
4. You should attend the Wall Colmonoy Brazing school on Modern Furnace Brazing on Nov.3/4/5, 2004. The three day cource includes these brazing subjects, Design, Metallurgy, Atmospheres, Filler Metals, Preforming the Brazing Operation, Inspection and QC, and the Problem Solving Session. This is given annually twice a year.
5. Contact me for more information at 248-585-6400 x240 Tu, Wed, Th.

By Daniel

Date 10-29-2004 06:58

Thank you for your help Bob

By Vik Date 01-31-2005 19:14

Hi, I'm new in a plant where works with INCO718/CRES347 furnace brazing. How can I evaluate the brazeability of the filler metal AMS4777 (What kind of testing)? Is a metallographic inspection enough, after the braze?
Thanks in advance for your help.