[Paul Wheaton]

I have a neighbor here that is trying to solder stainless steel to high speed steel. He's wondering what kind of solder to use. He's tried google and he's tried calling around (send it to us and we'll charge you to do it). My neighbor is trying to start a business and this is one part that he's missing.

Anybody know about this sort of thing?

Are there better forums to ask in?

 

[Guest]

It is pretty tough to give an answer without all of the information.

How much stress will be on the joint, what tolerances for fit, etc.

Without knowing more, I would plan on brazing the joint rather than soldering it. Brazing does of course require higher temperatures.

I guess as an experiment a person could try silver solder with proper fluxing.
I expect that the metals need heated higher to assure a good bond, so it seems that silver solder would be the better choice. I am however just guessing.

 

[Ross]

Sounds like he's trying to add something to a drill bit. Heat will take the temper out of the HSS so if it's a low stress addition he'd be better off using a silicone glue or epoxy. Perhaps it could be drilled and riveted on. Otherwise, MIG weld it and retemper.

 

[Paul Wheaton]

My neighbor says that I asked the question wrong. He's looking for information on "silver soldering" (as suggested above) and not just soldering.

I know that he showed me some of the stuff he is making about a week ago. It was a small, hand held tool.

Does this help?

 

[agmantoo]

Your neighbor needs to read about preforms if he is going to do intricate or volume silver soldering. Here is a site http://www.alphametals.com/products/preforms/
For silver soldering by hand he needs a specific silver soldering material which can be found here http://www.metafusionindia.com/sb.html
He will have to use trial and error to refine his skill at joining these materials. Once he gets the hang of it , the process will go rapidly.

 

[moopups]

The name 'high speed steel' is still puzzling to me, a more familiar name would help. Could he mean 'cold rolled' steel like you buy at the hardware store? Its dencely pressed, shiney and usually comes in 3 foot lengths.

The opposite is 'hot rolled' steel, purchased at supply houses, usually available in 20 foot lengths, the finish is rough, like sand cast.

They are both 'mild' steel, general purpose stock, the only diferance is the cold rolled is much more uniform in size.

Silver solder surfaces must be exceptionally clean to apply solder, heat must be very uniform, and keep in mind no solder will adhere to chrome surfaces.

 

[Ducks limited]

The name 'high speed steel' is still puzzling to me, a more familiar name would help. Could he mean 'cold rolled' steel like you buy at the hardware store? Its dencely pressed, shiney and usually comes in 3 foot lengths.

The opposite is 'hot rolled' steel, purchased at supply houses, usually available in 20 foot lengths, the finish is rough, like sand cast.

They are both 'mild' steel, general purpose stock, the only diferance is the cold rolled is much more uniform in size.

Silver solder surfaces must be exceptionally clean to apply solder, heat must be very uniform, and keep in mind no solder will adhere to chrome surfaces.

I've heard HSS and "tool steel" used for the same type of metal. Where I work uses D-2 (high carbon) steel for knives to cut paper. The metal is ordered as tool steel. This is machined to shape before sending it to a heat-treater to be hardened. Also, the most common drill bits are HSS. Hope this helps.

 

[moopups]

Ducks Unlimited, why did you copy my post before yours? Does it make you feel superior to do such? It was the post before yours, do you think the readers have that short of a memory? I see this practice everywhere here; its space wasteing, unnecessary, and degradeing.

 

[westbrook]

In a nutshell - High Speed Steel is a carbon alloy that can be treated to very hard properties, makes a great cutting edge.


High Speed Steel is 'Tool Steel'. A high carbon heat treated steel, the heat treat makes it very hard and you can grind a sharp edge on it, if you are braising or soldering it you want to avoid heating the cutting edge so the process needs to be done rapidly with a heating torch locally to the joint. Avoid heating the cutting edge which will temper or soften the high speed steel.

yes Silver solder is what he wants to use.

westbrook

 

[Guest]

I have a neighbor here that is trying to solder stainless steel to high speed steel. He's wondering what kind of solder to use. He's tried google and he's tried calling around (send it to us and we'll charge you to do it). My neighbor is trying to start a business and this is one part that he's missing.

Anybody know about this sort of thing?

Are there better forums to ask in?

typical carbon st to sst is TIG with inconel filler (WPS2102)
for cases where mechanical rigidity needed. I've not heard
of brazing/soldering but if need electrical/ground connection
could drill & wire between.

 

[owhn]

Perhaps I am slow to get into the discussion.

From Brazing (second edition) ASM International, 2003.

"High speed steels have relatively high percentages of such alloying elements as tungsten, molybdenum, chromium, and vanadium. Their carbon contents normally are much lower than those of carbon tool steels."

"Torch brazing using BAg [and other] filler metals."

"Localized heating for brazing may decrease the hardness of heat treated steels when the brazing temperature is above the tempering temperature of the steel..."

All stainless steels are difficult to wet because of their high chromium content ... In torch brazing of these base metals, fluxes are required to reduce any chromium oxides present."

Filler metal BAg3, which contains 3% Ni, is probably the silver-base filler metal selected most frequently ...

Brazing temperature range for BAg3... is 1270 to 1500 degrees F.

"Maximum temperature service of silver brazed joints is 700 degees F."

Flux for silver brazing these types of base materials ...
paste ... FB3A (1050-1600 degrees F) or FB3B (1050-1700 degrees F). (There are others.)

Do you know the use, what the materials are specifically?


HTH

owhn
engineer/writer

 

[owhn]

I should point out that there are MANY choices of matereials, and MANY vendors for them all too.......

here is just one ...

http://www.lucas-milhaupt.com/htmdocs/brazing_support/technical_msds_safety/filler_metals.html

He/she may want to totally avoid cadmium ... BAg 4 is cadmium free silver base filler metal... but otherwise similar ...

What I would like to know is what kind of shop is this that isn't familiar with these topics and materials but expects to use them properly?

Besides preforms (might be hard to justify for a one-off project), there are issues of surface preparation, joint design and service loads, corrosion, base metal metallurgy, service temperatures, quality control, etc.

now, back to work


owhn