Bronze vs. Phosphor Bronze Identification

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SCBryan
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Joined: Tue Feb 10, 2015 12:37 pm
Location: Fort Wayne, IN

Bronze vs. Phosphor Bronze Identification

Post by SCBryan » Mon Jul 13, 2020 8:17 am

Here is a question for more experienced board members. I have some pieces of material I received that may be either bronze or phosphor bronze but are not identified. Is there a visual way to tell which is which?

Steve Goodbody
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Re: Bronze vs. Phosphor Bronze Identification

Post by Steve Goodbody » Mon Jul 13, 2020 12:07 pm

Hi there,
There are a whole variety of bronzes unfortunately, with widely varying levels of toughness, strength, machinability and solderability.

If comparing 932 bronze (as often used for live steam fittings) with what I think of as phosphor-bronze (a bearing material), phosphor-bronze is redder and more like copper in appearance.

In my experience 932 bronze turns easily and like brass (small chips) whereas phosphor bronze is tougher and turns more like copper - with spirals. Again, in my experience, phosphor bronze tends to have lots of internal stress and, when a hole is drilled, the darned stuff often contracts and tightens back onto the drill.

Finally, in my experience aluminum bronze looks more like 932 bronze and machines more like phosphor bronze!

Hope that some of this is of help.
Best regards
Steve

hoppercar
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Re: Bronze vs. Phosphor Bronze Identification

Post by hoppercar » Mon Jul 13, 2020 12:19 pm

The phosphor bronze, is more red, due to the higher copper content....when turning...the chips are kinda long and spirally....drilling it, I have had it collapse and pinch the drill, resulting in the invention of some colorful metaphors.....bronze..of which there are numorous grades...has less percentage copper, and more tin....it tends to turn small chips, like yellow brass.

SCBryan
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Location: Fort Wayne, IN

Re: Bronze vs. Phosphor Bronze Identification

Post by SCBryan » Mon Jul 13, 2020 3:35 pm

Thanks for the replies.

Harold_V
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Re: Bronze vs. Phosphor Bronze Identification

Post by Harold_V » Mon Jul 13, 2020 3:44 pm

There's one alloy that has been overlooked, it being leaded phosphor bronze. In appearance, it is virtually identical to phosphor bronze, but it is likely the best machining alloy available. It displays none of the troublesome features of phosphor bronze.

Determining an alloy by appearance can be a slippery slope. For example, one would be hard pressed to discern phosphor bronze from beryllium copper. One is harmless, while the other is not.

H
Wise people talk because they have something to say. Fools talk because they have to say something.

hptwin
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Re: Bronze vs. Phosphor Bronze Identification

Post by hptwin » Mon Jul 13, 2020 8:42 pm

You could take a sample of the bronze in question to a scrap metal dealer who deals in nonferrous alloys. They usually have hand held X-ray spectrometer and can "shoot" it and show you the composition of your sample by percentages of elements. Most yards around here are happy to do this as a goodwill gesture. Then go online and find out just what you have by comparing it to listed alloys. You may not get an exact to three decimal places match, but you can know for certain that you don't have beryllium or some other nasty ingredient.
Play the "steam card" when asking for help, most people like steam trains.
Best regards, Mike (hptwin)

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SteveM
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Re: Bronze vs. Phosphor Bronze Identification

Post by SteveM » Tue Jul 14, 2020 11:05 am

Harold_V wrote:
Mon Jul 13, 2020 3:44 pm
...one would be hard pressed to discern phosphor bronze from beryllium copper. One is harmless, while the other is not.
It's easy to tell them apart - at least post-mortem.

Steve

Harold_V
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Re: Bronze vs. Phosphor Bronze Identification

Post by Harold_V » Tue Jul 14, 2020 4:08 pm

True, that.
Interestingly, there was little to no protection for the worker when I was serving my apprenticeship. Safeguards were not yet in place. Not even for asbestos.

Now to determine if we're better off than we once were. Life is now easier/harder, depending on one's objective.

H
Wise people talk because they have something to say. Fools talk because they have to say something.

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Greg_Lewis
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Re: Bronze vs. Phosphor Bronze Identification

Post by Greg_Lewis » Tue Jul 14, 2020 9:20 pm

So how bad is the beryllium? Is it instant death or is it one of those things that adds up over many years, or something in between?
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 30 years of turning perfectly good metal into bits of useless scrap.

optigman
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Re: Bronze vs. Phosphor Bronze Identification

Post by optigman » Tue Jul 14, 2020 10:00 pm

I would comment but fear my post would be deleted. Censorship is alive and well in the USA.

Harold_V
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Re: Bronze vs. Phosphor Bronze Identification

Post by Harold_V » Wed Jul 15, 2020 3:18 am

I used to subcontract work (primarily tooling) from Litton Guidance & Control in Utah. They had a mandate that dictated that an employee could work with beryllium copper for a maximum of 90 days total, and could not machine it again ever. As a result, they had a tendency to subcontract such work, so I machined it a few times.

It apparently accumulates in the body, and alters the lungs ability to exchange oxygen with blood. Beryllium copper itself is not toxic, so it can be handled safely so long as there is no dust created. Interestingly, it can achieve strength beyond that of chrome moly.

H
Wise people talk because they have something to say. Fools talk because they have to say something.

Harold_V
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Re: Bronze vs. Phosphor Bronze Identification

Post by Harold_V » Wed Jul 15, 2020 3:21 am

optigman wrote:
Tue Jul 14, 2020 10:00 pm
I would comment but fear my post would be deleted. Censorship is alive and well in the USA.
Feel free to comment. So long as your posts are not vulgar, do not attack others, are free from religion and politics, you are free to voice your opinion. We do not censor things here unless those rules are violated. Post as if your aged grandmother would read your words. Be polite. In other words, common decency.

H
Wise people talk because they have something to say. Fools talk because they have to say something.

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