Historic Alloy Steel Properties 4

[TTK]

Hello,

I am trying to identify the chemical and strength properties of high strength silicon steel used in the 1920's and 1930's.

More specifically, the steel would have been used in bridge construction and it would have likely been the highest strength steel being used in this industry at the time.

Does anyone know of any good sources of information for this data (free or fee-based)?

Thanks,

TTK

 

[JoeTank]

Honestly, I did not think there were any high strength steels at that time. ASTM A7, A9 and A10 were pretty common, but they all had yields in the range of 30 to 33 ksi. Their tensile stesses were about 55 to 60ksi.

Joe Tank

 

[TTK]

JoeTank,

Thanks for the reply. Silicon Steel was used sparingly in major bridges during the 1920's and 30's.

I have read that the steel mills did not market the material because their preference was to keep everyone using the carbon steels (why I do not know).

The silicon steel apparently had 70 ksi ultimate and 45 ksi yield, but I cannot find any information on the chemical composition of this steel.

I am working on a major bridge rehab and I beleive this steel was used for the primary members. We will be testing the material but I need to have a baseline chemical composition to compare the test results to.

Thanks again,

TTK

 

[EdStainless]

In my limited experience I have seen two different cases. Once we had steel that was nearly iron. Very low strength, but nice and clean.
The other case what higher strength, but a large amount of variation in properties.
You need to do some extensive hardness surveys in order to have some confidence in the scatter of properties.

= = = = = = = = = = = = = = = = = = = =
Still trying to help you stop corrosion.
formerly Trent Tube, now Plymouth Tube
eblessman@plymouth.com
or edstainless@earthlink.net

 

[JoeTank]

The ASTM website has a listing of ASTM Standards that have been WITHDRAWN. Check it out, you may fine your material listed there.

Joe Tank

 

[TTK]

I now know the material was first used in 1915, but the first ASTM specification for it was not created until 1925.

ASTM A94-25T
"Tentatiave Specifications for Structural Silicon Steel"

Fy(min) = 45 ksi
Fu = 80 to 95 ksi
Carbon (0.44% max)

The specification was withdrawn by ASTM in 1963 (poor weldability), but I was not able to find the actual withdrawn spec. on their website.

I would still like to find the silicon content of the steel, so if anyone knows of a way to get a copy of this withdrawn spec, please let me know.

thanks,

TTK

 

[unclesyd]

Here is a listing from the ASTM site.

http://enterprise.astm.org/filtrexx...s/newpilot.com/SUBSCRIPTION/WITHDRAWN/A94.htm

 

[unclesyd]

Look towards the bottom of this article and there is some information that may be of interest about your steel.

http://www.usace.army.mil/publications/eng-manuals/em1110-2-6054/c-7.pdf

 

[swall]

I found an old book of TTT diagrams published by US Steel and it lists two compositions for silicon steel with .50 nominal carbon content. One has .53 silicon; the other has 1.27 silicon. More recently, I have seen safety brake springs from China made out of an alloy similar to the latter (i.e. Cr-Si, without the chrome).

 

[metengr]

TTK;
Many of the original ASTM specifications began as tentative specifications that were revised based on use (good and bad expierence) and fabrication.

In this situation, it is always best to obtain actual material core samples of the steel to assure chemical composition and mechanical properties. I have seen this done before with minimal effort. I would not use any database properties to draw conclusions.

 

[TTK]

Thanks for all of the replies everyone.

Just to clarify, it has always been my intent to sample and test the steel (strength, hardness & chemical composition on several samples), but I would also like to have the original ASTM standard to compare the test results against.

I have an e-mail into ASTM to see if I can still purchase a copy of the withdrawn specification, but if anyone knows of any other source, please let me know.

Thanks again,

TTK

 

[Pressed]

The link below is a picture of specs from 1915. Is this what you need?

[URL unfurl="true"]http://www.flyupload.com/?fid=3317238[/URL]

There is a book called "A Decade of Bridges, 1926-1936" which sounds like a good match to your needs. I don't know if it has the data you want. If you have a good library nearby, I would think their exchange service should find one. Then again???

There is one listed here at the Smithsonian:

[URL unfurl="true"]http://siris-libraries.si.edu[/URL]

Good luck.

==========================================
Business Site

http://mech.e.tripod.com

------------------------------------------
Cycle Utopia.......

http://www.tailofthedragon.com

 

[TTK]

Thank you Pressed!

That's exactly what I was looking for...may I ask where you found it? If your source is prior to 1917, then all copyrights have expired and it's now in the public domain. If your source is newer than 1917, there is a chance that copyrights still apply.

You provided the steel spec from the Metropolis bridge, which is reported to be the very first use of this material in the US.

There is a chance the material specification changed between its first use in 1915 and when the tentative ASTM specification was eventually written in 1925, but the 1915 spec, along with my testing program should be enough to go by.

This forum is a great resource...thanks again everyone!!

TTK