Brazing a structural component - thinkable?
Brazing a structural component - thinkable?
(OP)
Hi all.
We are looking to reinforce a stainless steel stressed skin structure. The stainless steel used is 301LN 1/2 Hd. Someone suggested exploring the addition of a brazed stainless steel flat bar, because it may be easier than welding. Existing skin is spot-welded to stiffeners, but seems too thin with insufficient spot welds.
Naturally, I have many questions.
Static shear strength of brazed joint
Fatigue strength (or any data)
Any long-term corrosion issues?
Any references would help.
tg
We are looking to reinforce a stainless steel stressed skin structure. The stainless steel used is 301LN 1/2 Hd. Someone suggested exploring the addition of a brazed stainless steel flat bar, because it may be easier than welding. Existing skin is spot-welded to stiffeners, but seems too thin with insufficient spot welds.
Naturally, I have many questions.
Static shear strength of brazed joint
Fatigue strength (or any data)
Any long-term corrosion issues?
Any references would help.
tg





RE: Brazing a structural component - thinkable?
RE: Brazing a structural component - thinkable?
RE: Brazing a structural component - thinkable?
RE: Brazing a structural component - thinkable?
You will need to check and see what degree of stress relief you get on the 301LN after the 1400F braze cycle.
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube
RE: Brazing a structural component - thinkable?
I'm unclear what is "too thin" and why it "seems" that way.
Poor product performance, or visual based concerns with weld quality or the stiffener itself, or problems with manufacturing?
Are you leaning toward brazing the existing stiffener, or brazing an entirely new style of stiffener ?
Are you making the panels in-house, or buying them? Regardless, if this panel creation is a significant part of the product cost I'm thinking spot welding is likely to be the most economical method of attaching ribs or stiffeners, by a long shot.
Perhaps it is a matter of re-designing the stiffeners a bit, and adding a few strategically spaced spot welds.
Spot welding is good enough for Porsche much of the time. (and other OEMs as well)
https://www.youtube.com/watch?v=des-xY65nMs
RE: Brazing a structural component - thinkable?
RE: Brazing a structural component - thinkable?
There was quite a bit of basic research conducted by the US aerospace industry regarding furnace brazing of lightweight structures using high-temp metals (like stainless steel) back in the 1960's. So you should be able to find plenty of technical references on the NTRS and DTIC websites. Here's one fairly recent paper on analyzing brazed joints.
RE: Brazing a structural component - thinkable?
= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube