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KIMURA
05-06-2004, 02:26 PM
Taken out of "A6M in Action" Squadron/Signal publications.

"With weight reduction being of prime importance most engineering inovations were directed to this end. The wing was built around a 1 piece main spar of Extra-Super-Duraluminium, a light weight aluminium alloy used for the 1st time in a/c mainspar construction was similar to the 24S aluminium used by the US several years later."

Due to my work as engineer, I'm also interested in the different chemical components and the percentages they were mixed in, of either ESD or 24S, that was used at that time. Does anyone have more details of either of those alloys?

Kimura

KIMURA
05-06-2004, 02:26 PM
Taken out of "A6M in Action" Squadron/Signal publications.

"With weight reduction being of prime importance most engineering inovations were directed to this end. The wing was built around a 1 piece main spar of Extra-Super-Duraluminium, a light weight aluminium alloy used for the 1st time in a/c mainspar construction was similar to the 24S aluminium used by the US several years later."

Due to my work as engineer, I'm also interested in the different chemical components and the percentages they were mixed in, of either ESD or 24S, that was used at that time. Does anyone have more details of either of those alloys?

Kimura

F16_Fatboy
05-07-2004, 10:19 AM
From "Zero" by Robert Mikesh.

"The wing spar of an aircraft is generally the heaviest single member of the structure.To substantially reduce the weight for this fighter, a newly developed aluminium alloy of exeptional strenght was used. This was Super Ultra Duralumin, sometimes called Extra Super Duralumin (ESD). Pioneered and developed by Sumitomo Metals Company, this leightweight material was in itself a landmark development in Japanese aviation technology. The alloy was rich in zinc aand chrome and was similar to to medern-day 7075 aluminium material. Compared to previusly used alloys, ESD had a 30-40% greater tensile strenght and 70-80% higher yield point."

Read somewhere that this material ages badly and can be scoped out with eg a screwdriver on surviving Zeros.
FLSTF

http://img41.photobucket.com/albums/v125/F16_fatboy/Album1/sig_fatboy.jpg

KIMURA
05-07-2004, 11:40 AM
Thanks very much

Just found out the correct designation is AA 7075 T6 DIN# 3.4365. But I don't know any AL alloy that contains chrome. It seems remarkable that the Japanese created that high end alloy so early.

The key to AA7075 T6
5.1-6.1% Zn
2.1-2.9% Mn
1.2-2.0% Cu
0.2% Ti
<0.5" others

yield point 510-550N/mm2. (that's higher than most average quality steal with around 400N/mm2.)

Kimura

SKULLS Virga
05-07-2004, 11:54 AM
Very interesting thread.

What is the definition of yield point?

Gibbage1
05-07-2004, 12:23 PM
One thing about the Jap aluminum is it was lighter and stronger, but very brittle. A bullete would pearce US aluminum, but shatter japanese aluminum causing more damage. Its said you could punch your finger though a Zero's wing skin! I also read a pilot account flying the Chino Zero and there are about 4 footsteps on the wing. If you miss one, you go through the wing!

No wonder they were falling appart so easy in WWII.

My post's are my asumptions only, and in no way linked to fact. I am not an official 1C, Ubi, or Russian Red Rocket spokesman.

"Most P-39's were sent to the Russians - so I guess that was an American secret weapon against our Russian allies."

Stan Wood, P-38 pilot who also flew the P-39.

Giganoni
05-07-2004, 01:02 PM
Lighter and stronger, but brittle? Isn't that kind of a contradiction? What do you mean by stronger? Stronger than what? What was used on US Planes? Do you mean stronger as in able to cope with aircraft manuvers?

Also the Japanese were the first at least in the Pacific war to finish the bores (and sometimes the bolt) of their Arisaka 99 rifle (whose early war type 99s were some of the best bolt-action rifles of WW2) with chrome. This kept the rifle protected from harsh tropical climate and normal use. The US with the M1 only incorporated it much later. So the Japanese did some inventive stuff ot be sure.

The Arisaka was a good rifle until the late war models arrived. Even the British army had the Arisaka as a standard weapon in WWI, Lawerence of Arabia used it.

Gibbage1
05-07-2004, 01:44 PM
There is a differance between how strong a metal is, and how it brakes or gives. If you take a 1/2 peace of US aircraft grade aluminum from WWII and apply force to it, it will resist to a point, and then give. The US metal would give, but bend. The Jap aluminum would resist more, but brake when it does give.

My post's are my asumptions only, and in no way linked to fact. I am not an official 1C, Ubi, or Russian Red Rocket spokesman.

"Most P-39's were sent to the Russians - so I guess that was an American secret weapon against our Russian allies."

Stan Wood, P-38 pilot who also flew the P-39.

F16_Fatboy
05-07-2004, 01:54 PM
yield point The coordinate on the stress-strain curve of a material in uniaxial tension or compression representing the onset of significant plastic deformation. Typically the fracture point for brittle materials and the coordinate at an offset strain of 0.2% for ductile materials .

Synonym : elastic limit

FLSTF

http://img41.photobucket.com/albums/v125/F16_fatboy/Album1/sig_fatboy.jpg

tenmmike
05-07-2004, 02:07 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by KIMURA:
Thanks very much

Just found out the correct designation is AA 7075 T6 DIN# 3.4365. But I don't know any AL alloy that contains chrome. It seems remarkable that the Japanese created that high end alloy so early.

The key to AA7075 T6
5.1-6.1% Zn
2.1-2.9% Mn
1.2-2.0% Cu
0.2% Ti
&lt;0.5" others

yield point 510-550N/mm2. (that's higher than most average quality steal with around 400N/mm2.)

Kimura<HR></BLOCKQUOTE>chromium(cr)is in almost all 5000 series about half of the 6000 series and almost all of the 7000 series for example 7075 has .23% cr along with the other alloying elements you mentioned...source aluminum standards and data from the aluminum association

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Gibbage1
05-07-2004, 02:17 PM
Ya. I was trying to say it in english.

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by F16_Fatboy:
yield point The coordinate on the stress-strain curve of a material in uniaxial tension or compression representing the onset of significant plastic deformation. Typically the fracture point for brittle materials and the coordinate at an offset strain of 0.2% for ductile materials .

Synonym : elastic limit

FLSTF

http://img41.photobucket.com/albums/v125/F16_fatboy/Album1/sig_fatboy.jpg <HR></BLOCKQUOTE>

My post's are my asumptions only, and in no way linked to fact. I am not an official 1C, Ubi, or Russian Red Rocket spokesman.

"Most P-39's were sent to the Russians - so I guess that was an American secret weapon against our Russian allies."

Stan Wood, P-38 pilot who also flew the P-39.

tenmmike
05-07-2004, 02:27 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by KIMURA:
Taken out of "A6M in Action" Squadron/Signal publications.

"With weight reduction being of prime importance most engineering inovations were directed to this end. The wing was built around a 1 piece main spar of Extra-Super-Duraluminium, a light weight aluminium alloy used for the 1st time in a/c mainspar construction was similar to the 24S aluminium used by the US several years later."

Due to my work as engineer, I'm also interested in the different chemical components and the percentages they were mixed in, of either ESD or 24S, that was used at that time. Does anyone have more details of either of those alloys?

Kimura<HR></BLOCKQUOTE>also i went to a old engineering book(1954) to look up the 24s that was mentioned and it was of this composition cu 3.7-4.9% mg 1.2-1.8% mn .3-.9%

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KIMURA
05-07-2004, 02:44 PM
Tenmike, I'm not very familar with the US designation of stuff, sorry. After DIN (German Institute for Standardisation) 3.4365 is the same to the US 7075 T6, but for the DIN 3.4365 an old DIN designation shows up. The old designation ALZnMgCu1,5 shows better what incredients the alloy contains. No chrome mentioned, have also a look at here. I wonder were the differences come from? http://ubbxforums.ubi.com/infopop/emoticons/icon_eek.gif

http://www.qualityproducts.de/quality/db_alu7075.htm

sry, it's written in German but the important stuff is easy to read, regardless of the language.

Kimura

tenmmike
05-07-2004, 03:11 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by KIMURA:
Tenmike, I'm not very familar with the US designation of stuff, sorry. After DIN (German Institute for Standardisation) 3.4365 is the same to the US 7075 T6, but for the DIN 3.4365 an old DIN designation shows up. The old designation ALZnMgCu1,5 shows better what incredients the alloy contains. No chrome mentioned, have also a look at here. I wonder were the differences come from? http://ubbxforums.ubi.com/infopop/emoticons/icon_eek.gif

http://www.qualityproducts.de/quality/db_alu7075.htm

sry, it's written in German but the important stuff is easy to read, regardless of the language.

Kimura<HR></BLOCKQUOTE> i spent a few yrs in germany 20 yrs ago i can sorta read it http://ubbxforums.ubi.com/infopop/emoticons/icon_cool.gif..now this is very intersting, your link says this
Manganese
2.1 - 2.9%
Titanium
0.2%
my book does not show either of those elements in 7075 but the cr is about the same as for ti (.2%) and what it showes for Manganese is what my book showes for magnesium (2.5%)

http://www.2-60inf.com/2-60_crest.gif 84-91

Yukikaze
05-07-2004, 05:51 PM
Maybe this will help:
Aluminum 7075-T6; 7075-T651

Component Wt. %
Al 87.1 - 91.4
Cr 0.18 - 0.28
Cu 1.2 - 2
Fe Max 0.5
Mg 2.1 - 2.9
Mn Max 0.3
Other, each Max 0.05
Other, total Max 0.15
Si Max 0.4
Ti Max 0.2
Zn 5.1 - 6.1

This is the kind of information you will find 3.1b test certificate coming with the material.
The old DIN Designation ALZnMgCu1,5 describes the biggest components in this alloy.