Bending Yield Fty Recycle Yard Aluminum

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proppastie

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Previous Home Brinell test for hardness pegged this aluminum as 5052 H36 with a yield of 29 Kpsi...
I am getting ready to use some of this in a critical location so I decided to do another couple of tests....I did two tests the with a large yield as shown in the picture of 38 Kpsi and a very slight deformation maybe less than 2 deg at 27 Kpsi.
 

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karmarepair

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That's not a Brinell test. The Brinell test presses a carbide ball of specified diameter into the test sample at a specified pressure, and the diameter of the resulting dent is accurately measured. Brinell hardness relates directly to tensile strength.

Brinell Hardness Testing
In the traditional Brinell test, the ball size, and the indentation pressure are standardized, for several reasons: comparability between operators and across metals, and to allow use of pre-computed tables are a couple that come to mind. The app Proppastie links to allows any size indenter and any force that plastically deforms the subject metal. Call it what you want it; it's using the same physics. And for sorting random bits of aluminum by strength, it looks Good Enough to me...
 

proppastie

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That's not a Brinell test
no........ it is a "Home Brinell Test" :) ........Its not a tensile strength test either as.....a true coupon test would pull in plane and measure the deflection until it snapped......and print out a nice curve to show the exact load at the yield point......but it is the best I can do with the tools I have
 
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Mad MAC

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Note that your bending stress results are a function of thickness squared, so be very careful measuring the initial thickness, as the results will be more sensitive to errors than one would normally expect.
 

proppastie

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Note that your bending stress results are a function of thickness squared, so be very careful measuring the initial thickness, as the results will be more sensitive to errors than one would normally expect.
certainly lots I do not understand....for example it bends a little way and stops.....is that because the extreme fibers allowable stress increases slightly?....or because of the change of the "Moment of Inertial" as regards angle/area of cross section in the bent state vs direction of load vector... The thickness is larger vs the load vector at the site of bending as the angle changes so...it makes sense the load needs to increase to continue bending.....thanks
 
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