Any metallurgists around? [Archive] - Glock Talk

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BB62
11-28-2006, 21:27
I'm from Cincinnati, and I'm reposting this here since Northern KY is just south of us...

HELP! Bear with me, if you would...

Last year at about this time I appealed for help for my son's 7th grade science fair project, the hypothesis being "The greater the caliber, the greater the penetration".

Help was amply offered in the form of customized .357 ammo, pistols of various calibers, etc. That help and my help, together with my son and his partner's diligent efforts added up to the boys winning first place! Yipee!!

Although this year they proposed a project with rifles! I talked them out of it because (among other reasons) they needed to broaden their horizons.

Instead they chose to hypothesize about the strength of various metals. Their hypothesis is "Steel is the strongest metal".

I only know of two strength measurements for such materials - tensile and compression. My thought was to have them secure various metals - copper, steel, aluminum, titanium (!), etc. and have them tested for tensile strength using an apppropriate machine.

The reason I asked about metallurgists is that I thought one might have access to/information on metals and a machine which could do the testing.

(My nephew may have access to a pulling machine through his college, but it is not a definite. Getting metal samples is less clear, as I don't have the specifications since we haven't nailed down the machines.)

Any help in the direction of securing a testing machine and/or metal samples is GREATLY appreciated.


Thanks much,
BB62

SmithShooter
11-29-2006, 01:59
I am no metalurgist but I can certainly tell you that Titanium is far far stronger than Steel, when measured by weight. This is to say, Titanium is roughly as strong as an equal volume of Steel in most respects, while weighing about 40% less.

http://en.wikipedia.org/wiki/Titanium is a good starting point for research but I suggest you independently verify the information contained there as wikipedia is not usually considered a usable primary reference in academic circles.

I applaud you taking an interest in your son's academic career and wish him the best of luck.

P.S. My wedding ring is made of Titanium so you might say im a bit of a fan of the stuff :)

ede
11-29-2006, 03:31
charpy v notch test is often used as a test. the testing method in part will depend on what you're looking for. lacking a proper testing maching i think you could rig up something on a hydrolic press using a fixture and a gauge to read line pressure. you can get an idea about a fixture by looking at ones for testing weld straps. you could make the assumption that the stronger material will require more test pressure to bend in the fixture, all else being equal.

Flinter
11-29-2006, 18:05
I'll try to post some info from my metalurgy text book in the next 2-3 days. I'm still unpacking, and my library is still over across the river at our old house. If you haven't heard from me by Sunday afternoon, drop me a PM and remind me.:thumbsup:

BB62
11-30-2006, 22:37
Thanks much, I appreciate it.


BB62

Flinter
12-03-2006, 19:12
Ok here goes a little highlights from my metallurgy text, "Metallurgy Fundamentals" by Daniel A. Brant, 1992. Publishers, The Goodheart-Willcox Company, Inc. ISBN 0-87006-922-5

There are 3 key mechanical properties, Hardness, Strength, and Brittleness.

Hardness- Acheived by alloying. Defined as- A measure of the resistance to deformation.

Strength- Many forms of strength, tensile, compressive, shear, fatigue, impact and flexure.

Brittleness- The less metal stretches the more brittle it is. The opposite of Brittleness is Ductility.

This subject can be very broad. If there is a more focus area you wish me to look just let me know, and I'll see what I got. I got a few books of the subject of metals and working metals. :supergrin:

BB62
12-04-2006, 21:52
Thanks for the post.

I will prompt the boys to discover the various ways of describing a metal's properties such as those you have laid out.


BB62

BB62
12-09-2006, 14:27
In addition to asking the boys questions so they can discover the information you shared, below are the questions I have posed to them so they can establish a base of knowledge.

Any additions/suggestions appreciated...
***********

- What defines "metal"?

- What are some properties or characteristics of metals?

- How do metals differ from one another? WHY do metals differ in strength or in other ways?

- How do metals differ from other elements?

- What is an alloy?

- Is an alloy a metal?

- How are alloys created?

- Is there a limit to the number of alloys possible?

- In what kind of circumstances are alloys used?

- What are some the various ways of stating a metal's "strength"? In other words, are some metals strong in one way, but weak in another?

- Related question: why might one favor the use of one metal over another for a particular application?

- How do metals (or do they?) work with other materials to increase various attributes of the finished product?

Flinter
12-09-2006, 17:39
BB62, I can add some more very relevent and important questions they could answer

1. What are the non ferric metals?

2. What are their prefered usages or applications?

3. What makes a metal ferric or non ferric?

4. Are non ferric metals magnetic (could possibly be rolled into one of the above questions)?

And while I hate to admit it, there is another line they could look up in relation to metals, and that is when it's best to not use a metal.

BB62
04-11-2007, 21:07
Thanks very much for everyone's contributions.

I just wanted to post an update here about the boys' project. Besides researching and looking over the information/resources suggested here, we also visited a number of places. Here are the highlights of the project:

The failure testing was done by HC Nutting here in Cincinnati by George, their very nice lab manager and Uwe, their welding engineer.

The metal was contributed by both HC Nutting and Central Steel & Wire.

For the science part, I took them the the main branch of the Cincinnati Public Library and immersed them in books for about 2 1/2 hours.

Last, and CERTAINLY not least, Rob Comstock, a materials engineer from AK Steel was very, very generous with his time and really gave the boys some intense technical information about metals, both elements and alloys.

In looking at other 8th grade projects, I waaay overdid it with exposing them to information, but they learned a great deal and really knew their stuff. I was very proud of them.

For the second year in a row they won First Place!! :)


BB62

TreehugginGlock
04-11-2007, 21:50
Congrats! :wave:

Flinter
04-15-2007, 16:53
I second the congratulations. Metalurgy is a tough subject, and very involved. It tied my brain in knots during school.