h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Entry: Melting Points of Common Metals - A2260063
Author: FordsTowel - U227087

Kinda surprised me that I couldn't find the melting point for aluminum.
Here's a table that should be in any guide to Earth.

Um... yes, a nice handy reference entry.

What order did you say the table is in? Well, it isn't.

Once upon a time, some of these were standard reference points in the temperature scale, and 1063C seems to ring a bell. Such definitions might be worth a mention.

By the way, http://www.world-aluminium.org/production/processing/properties.html has the melting point of Aluminium as 660C.

Hiya OH, Thanks for checking in!

On my screen it appears to be in order of 'increasing temperatures'; What order does it appear on your screen?

Yes, my table has 660 C for aluminum as well.

I got to wondering because of a thread I found on line that referred to a material called Alumalloy(TM). It sounds like it would be great for fixing stuff as it melts at 720 F. (Basically propane torch soldering temperatures.)

This made me wonder how much of it could actually be aluminum, because I remembered it having a melting point over 1200 F (or rather, over 600 C).

It looks like it must contain a lot of Tin, Lead, and maybe a little Zinc.

Strange that I haven't been able to find the MP of antimony, yet.

Found it!

Antimony is now included.

Sorry to you, but I was I bit quick replying before. I usually give fuller details. Anyhow, the distracting furore has died down now, so I'll try to be a bit more composed now.

There is a serious problem in the table, as manganese follows iron, and has higher MP in Fahrenheit, but not in Celsius. Other metals following iron have the same problem, so perhaps only iron is wrong.

The list of metals is also strange, and I am mystified how you arrived at it. For example, tungsten (a metal) is missing, but silicon (a non-metal) is present. I think uranium is a metal too, as it certainly gets extruded like steel (alloys of iron), but with more difficulty than most steels. Then sodium, potassium and cadmium are definitely metals, and I think caesium too (these are off the top of my head), and don't forget that mercury is a metal! I know the title says common metals, but I would have thought that tungsten is common (in just about every incandescent lamp), but rhodium and indium are not. I have not even mentioned the so-called rare earth metals (oops, I just did).

I think I would have downloaded a periodic table from somewhere, and then deleted the non-metals. I haven't had time (or bothered) to do that, as it is your entry. I have also had second thoughts about the entire concept of the entry.

I think you might consider either giving more details which are temperature related (like the MPs of some metals being recognised calibration temperatures for such things as optical pyrometers), or just give some of the properties of the metals other than the MP, for example density, conductivity (electrical and thermal), tensile strength... the list goes on. Even just on temperature, the metals have boiling points, and iron and nickel (and perhaps others) have important Curie temperatures (at which their magnetic properties disappear). The melting points alone seem to be of limited use, giving the soldering/welding temperature, or the usefulness as a filament material in light bulbs (having to remain solid when incandescent).

Altogether, if the entry is to stand as a reference table, it had better be both complete and accurate.

On purely presentational matters, entries destined for the EG should not contain pictures. In the table, a line therein has greater prominence than the caption, and the temperatures would probably benefit from being right justified.

Hi again, OH.

I didn't notice the iron thing; but I am certain you must be right, and I will attend to it.

Tungsten should most definitely be included. And there are definitely advantages to the right justification (perhaps even added commas.) And I realize that the artwork always goes, but that's if and when it gets accepted, so no worries there.

I think that I'll take this out of Peer Review for a major refit.

Accuracy would be nice, I agree; but I guess completeness is a function of intent. I could perhaps come up with a more accurate title, but the intent was to cover metals most likely used in home shops, jewelry shops, machine shops, and maybe small foundries. Few people ever smelt, solder, braze, or weld substances like uranium.

There is another option. If you truly think that a more complete and expanded table would be a helpful entry, I'm all for it. May I suggest that you are probably better fitted for the task?

If you have an interest in taking the project for your own, I'd be happy to back off and leave it to you. (In fact, I'm pulling it out of Peer Reveiw, at least til I get your response.)

Ever in favor of an increasingly accurate Edited Guide, Yours,

Hey, Hairy!

I tried starting from scratch. See if this is closer to what you would have wanted to see, and if any of it will help should you still want to improve upon it.

I hadn't intended that you pull it from peer review, but there, you've done it.

Its your entry, so if you want it to be about jewellery materials, thats fine. If you just describe them as that, rather than metals, or even common metals, the comments would have been different. As the new entry is now, I would say that Si, C and P are not metals. Your choice of units for weight as troy oz/cubic inch suggests jewellery is indeed your area of interest. Perhaps then, with a few sentences of introduction about soldering/brazing/welding, just mentioning melting points would be perfectly reasonable.

I have no plans to write anything about metals, but if I did, as a former electrical/electronics engineer, I would be rather interested in the multitude grades of brass. A mechanical engineer might be interested in materials such as phosphor bronze, gunmetal and whitemetal. There may be an element of writers choice in what's included, but the original gave no indication of selectivity.

Have fun with the entry.

Hairy, Thanks for continuing your interest.

Your suggestions of additional materials are intriguing. Might you know of a source for similar figures? Meanwhile, I've moved it to Writing Workshop, where I'll also work on the title and lead-in.

All hints, comments, and suggestions are gratefully received.

I've added a comment to the other thread (which is at F57153?thread=377030) for all those that aren't subscribed to the WW


Whisky

BTW, I think the Entry could profit from some more time in WW

I also posted there.

HELL

Oh, sorry...

It's already (still) there (in WW)... I thought it was in PR

I'm confused... No... I am not... err... Later...

HELL

Just to avoid confusion:

I removed the piece from PR, as I too felt it needed more substantial work. It is now in WW.

PLEASE POST any thoughts, comments or suggestions on That thread.

Your's for a more efficient use of thread,

Erm, whilst many of the igure appear ball park figure accurate, they're of by quite a margin on some according to the periodic table on my office wall, are you sure they're accurate and up to date, you've also got carbon there and that's not a metal but if you want it's melting point it's 3652 degrees C, guess that must be or graphite. Also, what order are they in? Certainly not atomic mass whih would be sensible, also SI units would be better than imperial

... just to let you know I'm dropping this thread, but will with stay with the other one in WW.