View Full Version : Mystery Metal

04-08-2006, 11:11 AM
Hi Friends
Yesterday I was working on a small project and grabbed a piece of 1" square x 3-1/2" long steel from my scrap bin, first thing I noticed was it felt heavy and the color was shiny compared to C-1018, thinking it might be stainless I checked to see if it was magnetic and it wasn't.
It was kinda tuff to machine although carbide worked well on it, drilling a .257
hole for 5/16-18 thread not to bad I opened it up to .261 and used all 3 taps
(brand new Hanson brand) worked OK.

Just wondering if you guys might have any idea of what it was.
My guess the weight was about twice that of C-1018.

Regards Graeme

John Stevenson
04-08-2006, 11:41 AM
Does it glow in the dark ? ;)

Seriously do you have a bit you can spark test on the grinder and let us know the colour.
Even though it's magnetic it could still be a 400 series stainless although most steels are about the same weight. Something being double would be unusual.

04-08-2006, 01:02 PM
Weigh it, and see if it really is heavier.
If so, it could be something wack like monel or another nickel bearing alloy.

04-08-2006, 01:07 PM
Are you saying that it is magnetic?

You might have a Fe and Ni based alloy. I think 1018 is about 0.284 lb/in^3 and the nickle alloys can get above about 0.305 lb/in^3. I don't know what that is in metric (as a lazy American, I'll export the math labor to those that want those numbers). A 50/50 split is around 0.298 lb/in^3, if I recall correctly.

04-08-2006, 02:41 PM
Weigh it. Steel is around 7.4 to 8 density and lead is around 11.34. However, tungsten is a ridiculous 19.6, even higher than gold or uranium. If it is a high tungsten alloy that would account for it. But, pure tungsten is dark gray, not shiny. Tungsten doesn't spark on a grinder hardly at all and is extremely hard to grind.

04-08-2006, 03:25 PM
I will make the assumption that Evans numbers are metric.

I did some internet searching and found a few nickle and tungsten alloys that are about 2x the density of "steel" but I have no idea what they look like, machine like, etc.

There are some W/Cu alloys that have a greater density, but are they magnetic? Looks like they are Chinese (no crap) manufactured.

Anyway, as a HSM on my weekend, I am doing too much "research", but hopefully pointing in correct directions.

04-08-2006, 03:30 PM
"I will make the assumption that Evans numbers are metric."

No, they are relative to the density of water which is a common way of expressing the density of materials. Water is 1, everything else is compared to that. You can use whatever units you wish.

04-08-2006, 04:05 PM
I hope you didnt waste the ONLY piece of Unobtanium! :eek: We've been looking for that!

04-08-2006, 05:06 PM
It is NOT magnetic, since machining it, I will have to do a lot of calculations to to now get the cubic inches left in it.


04-08-2006, 09:29 PM
Unlike density, which has units of mass per volume, specific gravity is a pure number, i.e., it has no associated unit of measure.

The most widely used reference substance for determining the specific gravities of solids and liquids is water. Because the density of water is very nearly 1 g/cm3, the density of any substance in g/cm3 is nearly the same numerically as its specific gravity relative to water.

If something is 7.85 times as heavy as an equal volume of water (such as iron is) its specific gravity is 7.85. Its density is 7.85 grams per cubic centimeter, or 7.85 kilograms per liter, or 7.85 metric tons per cubic meter.

In the "English" system of units the density of water is about 62.4 lb/ft3, so the near equality between specific gravity and density is not preserved in this system.

Boy I hope that clears up the "confusion", as Evan is technically correct, his numbers did not have units, I made the "approximate conversion" jump in my head, and left out the details. It has been over 25 years since my last formal chemistry education, and only a little more than 15 years since my last formal engineering studies. The cracks in my memory are wide and getting closer together every day. What is this thread about...

04-09-2006, 03:04 AM
"In the "English" system of units the density of water is about 62.4 lb/ft3, so the near equality between specific gravity and density is not preserved in this system."

Sure it is. Specific gravity is the ratio of the density of a material compared to that of water. It doesn't matter what system you use, cubic centimeters, cubic feet or cubic cubits, the ratio remains the same.

04-09-2006, 03:59 AM
Just as a reminder, the volume of an oddball shape can be found by immersing it in water and seeing how much water is displaced. Beats doing a lot of calculating and estimating where corners are rounded, edges rounded over, etc.

04-09-2006, 10:17 AM
It is NOT magnetic, since maching it, I will have to do a lot of calculations to
to now get the cubic inches left in it.

You machined it? What did it machine like?

04-09-2006, 11:13 AM
Evan (and all the others) :

I am not in disagreement with you, hopefully this will better explain what I was thinking about, I didn't want to get to far OT from the mystery metal question. Also I am not being consistant in significant figures, but I think "my" numbers are close enough to be "roughly right" and not totaly wrong (excepting my button pushing).

Specific gravity is the density of a substance divided by the density of water.

In physics, the word specific implies a ratio. Weight is the measure of the earth’s attraction for a body. The earth’s attraction for a body is called gravity. Thus, the ratio of the weight of a unit volume of some substance to the weight of an equal volume of a standard substance(usually water), measured under standard pressure (usuallly 14.69 lb/in^2, one atmosphere, anybody what is that in SI?) and temperature conditions (usually 4*C), is called specific gravity. The terms specific weight, specific density, and relative density are sometimes used to express this ratio. The standard temperature of 4°C is used whenever the density of liquids and solids is measured. The temperature of 4*C was selected because water has its maximum density at this temperature ("actually" 3.98*C or about 39.16*F). In the metric system, the density of water is 1 ("actually" 0.999720) gram per cubic centimeter at this temperature. Changes in temperature will not change the weight of a substance but will change the volume of the substance by expansion or contraction, thus changing the weight per unit volume. Water is nearly incompressible. But it does compress a little; it takes pressures over about 400 kPa or 4 atmospheres before water can reach a density of 1000.000 kg/m³ at any temperature.

Thus, the specific gravity is the ratio of its density to the density of water. If the specific gravity of a liquid or solid is known, the density of the liquid or solid maybe obtained by multiplying its specific gravity by the density of water. For example, if a certain substance has a specific gravity of 0.8, 1 cubic foot of the liquid weighs 0.8 times as much as a cubic foot of water—0.8 times 62.4, or 49.92 pounds. In the metric system, 1 cubic centimeter of a substance with a specific gravity of 0.8 weighs 1 times 0.8, or 0.8 grams. (Note: that in the metric system the specific gravity of a liquid or solid has the same numerical value as its density,but without any units, since water has a density of 1 gram/cm3, and since all of the units cancel).

More meds please, my head hurts from thinking to much this early in the morning. But I hope by the last paragraph everybody "understands" my other comment. I won't even try to explain the other "standards" that exsist, that use the concept, but in a way that is "easier" for them to use "in the "field" (medicine, specific industries, agriculuture...).

04-09-2006, 11:40 AM
Using my regular carbide tipped lathe tool (no chip breaker) some of the chips broke into small pieces and others where long curlies, drilling, the chips seemed normal and as I needed a .625 hole thru the 1" square a predrilled
39/64" and bored it to .620" (made a squeeling noise ) at a speed of 120 RPM
I finished with a machine reamer as I kept getting a tapered hole.
To-day I will try to get a weight ratio as I usually figure steel at .283 lbs.


04-09-2006, 11:47 AM
This is "probably" going to be taken wrong.....it isn't (repeat........ISN'T)meant as an insult, but.............

If you "really" want to know what the metal is.......why don't you just send a sample to your local metalurgist and pay to have it anylized (sp), instead of asking a bunch of people that have "no way on God's green earth" of correctly answering the question without a "whole" lot more information than you can possibly provide.

or............just use the stuff and don't worry about it..........

or...........sell it on Ebay as "Unobtanium" (I think Schutzhund called it that).....

Ya know.........I used to think that there weren't any "bumb questions"......only "dumb answers"........but then I got a computor and started joining BBS's and realized that there are really "both types"........Certainly (and not least) including "this answer".


04-09-2006, 02:28 PM
O.k. so I was off on the weight, I calculated the cubic inches left in the part
and they came to 1.69975 x .283 (lbs/cubic inch) = .4810292 lbs or
7.696468 ozs.
I weighed it on my wifes cooking scale and it came to 8-3/4 ozs.
The material looks alot like what the model railroad industry calls "nickel silver" as used for track and wheels.
My stock of it is all used up and I am guessing it has a lot of nickel in it.