Sites: GlobalSpec.com | GlobalSpec Electronics | CR4 | Electronics360
Login | Register
The Engineer's Place for News and Discussion®


Speaking of Precision

Speaking of Precision is a knowledge preservation and thought leadership blog covering the precision machining industry, its materials and services. With over 36 years of hands on experience in steelmaking, manufacturing, quality, and management, Miles Free (Milo) Director of Industry Research and Technology at PMPA helps answer "How?" "With what?" and occasionally "Really?"

Previous in Blog: Five Contributions of Nickel in Alloy Steel   Next in Blog: Scheduling Is Key For Preventive Maintenance
Close

Comments Format:






Close

Subscribe to Discussion:

CR4 allows you to "subscribe" to a discussion
so that you can be notified of new comments to
the discussion via email.

Close

Rating Vote:







4 comments

Iron - The Implied Element

Posted October 26, 2010 8:26 AM by Milo

Pure iron is barely harder and stronger than copper. Impurities are to iron, what paint is to an artist's canvas.

Red Ochre is Iron

The problem with iron at this level of purity is that it is too soft and too ductile for most commercial uses.

This means that the iron products that we know and recognize are relatively and deliberately impure.

Iron also has three allotropes or crystal forms, delta iron (body centered cubic) gamma (face centered cubic) and alpha, body centered cubic. I was originally taught* that delta and alpha iron were the same allotrope, a distinction that now appears to be a charming sign of old age… and the addition of impurities (alloying elements) have different solubilities based on these forms.

It is the addition of carbon and other elemental impurities which alter these allotropic forms that gives commercial iron and steel products their diverse properties.

When we look on the material certs that accompany our steel products , the first element that is reported is carbon. Carbon is ubiquitous, and has the dominant effect on the behavior of the iron based product to which it is part, even in the presence of large amounts of alloying elements.

What is implied by the certs is that after adding up all of the elements reported, the balance of the material is "iron."

In 2009 world Iron and steel production was estimated to be 1,219.7 million metric tonnes.

Physics trivia: Iron is the heaviest atom that can be made by the fusion of stars. Iron is is the 'ash' of stellar nuclear fusion. Iron is abundant- the fifth most abundant element on earth, and sixth most abundant in the universe. Our blood is red because of iron, and since iron is an essential part of our bodies, we can truly claim that we are "Stardust."

"We are Stardust, We are golden, We are billion year old carbon, and we got to get ourselves, back to the garden."

Iron is essential to almost all living things indeed it is key to the working of hemoglobin and oxygen transfer in humans, as well as in enzymes that are involved in the creation of DNA.

Our bodies store surplus iron in the liver, to cover for those days when we do not get our required 7 to 11 milligrams of daily iron.

When properly contaminated with carbon, manganese, a sprinkle of sulfur or phosphorous, iron makes some damn fine precision machined parts too!

Mostly iron, but the cert doesn't say so

*I was originally taught= Alloying Elements in Steel by Edgar C Bain and Harold W Paxton, 2nd edition:
"The metal iron, as shown in figure 1., exists in two isometric allotropic crystal forms: (1) alpha and delta iron, whose solid solutions are called ferrite (or delta ferrite) and (2) gamma iron whose solid solution is is austenite."

Cave painting

Poster

Lyrics by Jodi Mitchell, performed by Crosby, Stills, and Nash.

Editor's Note: CR4 would like thank Milo for sharing this blog entry, which originally appeared here.

Register to Reply

Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.
Guru
Popular Science - Weaponology - New Member United Kingdom - Member - New Member

Join Date: May 2007
Location: Harlow England
Posts: 15330
Good Answers: 544
#1

Re: Iron - The Implied Element

10/26/2010 9:31 AM

Early evidence of high five found in cave
Del

__________________
health warning: These posts may contain traces of nut.
Register to Reply Off Topic (Score 5)
Guru

Join Date: Jul 2006
Location: "Dancing over the abyss."
Posts: 4884
Good Answers: 240
#2
In reply to #1

Re: Iron - The Implied Element

10/26/2010 10:33 AM

Milo

__________________
People say between two opposed opinions the truth lies in the middle. Not at all! Between them lies the problem, what is unseeable,eternally active life, contemplated in repose. Goethe
Register to Reply Off Topic (Score 5)
Guru
Popular Science - Weaponology - New Member United Kingdom - Member - New Member

Join Date: May 2007
Location: Harlow England
Posts: 15330
Good Answers: 544
#3

Re: Iron - The Implied Element

10/27/2010 5:40 AM

How pure is something like a common soft iron nail? The sort of 6" round nail you can buy at any hardware shop.
I sometimes use 'em if I want to make something cold forged and primitive, say a medieval nail or a nice soft rivet as they are so soft and maleable (or do I mean ductile...? ). There's not enough carbon in 'em to harden or temper...
Hope this isn't too daft a Q
Del

__________________
health warning: These posts may contain traces of nut.
Register to Reply
Guru
Hobbies - Musician - New Member Australia - Member - Torn and breading Engineering Fields - Nanoengineering - New Member APIX Pilot Plant Design Project - Member - New Member

Join Date: Jun 2006
Location: Magnetic Island, Queensland, Australia
Posts: 3738
Good Answers: 75
#4

Re: Iron - The Implied Element

10/28/2010 5:55 PM

There was more than iron sucked out (up) back then!!

__________________
The Twain Has Met
Register to Reply
Register to Reply 4 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.
Copy to Clipboard

Users who posted comments:

Del the cat (2); ky (1); Milo (1)

Previous in Blog: Five Contributions of Nickel in Alloy Steel   Next in Blog: Scheduling Is Key For Preventive Maintenance
You might be interested in: Master Alloys and Alloying Additives, Finite Element Analysis Software, Specialty Steels and Other Iron Alloys