ASM Online Member Community

SAE Aerospace Material Specification AMS4011 is for 99.45% pure Aluminum as foil and light gauge sheet.  I have taken on an assignment to review and update, if necessary, the subject document.  It was first issued in 1968 and has had 4 revisions since then.  Unfortunately, I have no access to any prior information on or discussions about it.

This product is used "typically" for capacitors, electronic components, and sound/vibration damping tape but may have other applications.

There are a number of perplexing requirements, however.

The "foil" can have either a dry or slick surface condition, determined by placing drops of a water/alcohol solution and observing its wettability.  It appears that this is determined by observing this behavior with various percentages of the alcohol, but no actual criterion for acceptance is given (nor does it appear to be an attribute to be entered in the procurement document).  Interestingly, the surface is supposed to be "bright" on one side and "matte" on the other, but there is no discussion of which side is supposed to be tested for wettability or "oiliness".

There is a tensile test requirement on the foil per ASTM E354 in addition to a breaking load one for foil between 0.00017 and 0.00050 inch thick. The latter test can be performed on either a single thickness of the very-thin foil or on "specimens consisting of multiple thicknesses of product".  I would think that, if one of those foils failed, when the load is transferred all the rest would almost immediately giving a statistically invalid result.

I have not been successful in determining who makes or uses this product, how it can be successfully and unambiguously tested, and what properties are really important for its use. There's no problem with the light-gauge sheet requirements which seem pretty conventional.

I would appreciate any insight or experience anyone has in the testing ambiguities and practicalities, the (important) uses and properties requirements, and the source(s) of its production.

Dave,
I don't have any specific experience with that spec.  Regarding the mechanical testing, with such a thin material and resulting small cross-section, there is some difficulty in reading loads low enough.  So perhaps the idea is that using multiple thicknesses will bring the result up out of the noise.  You're right about the load transfer, but since tensile tests need to exceed a minimum, as long as failure hasn't happened below a certain load the lot would pass.

It appears that the Spec had Revision A in 1987, was last revised in 2009 and "reaffirmed" in 2014 if I interpret words at the global.ihs.com site correctly.  The originating organization's relevant committee may well have some survivors, at least the most recent group.  I have chased down technical committee members who authored or approved specs in the past and gotten answers or other leads to relevant information.

Matte vs. shiny are usually related to the finish on the final rolling pass.  It may be useful to identify how the AMS version is /different/ from other organizations' standards for similar materials.  For instance, this text was in an online version of QQ-A-1876 Federal Specification for Aluminum Foil, found online and mentioned elsewhere "nearby" to the AMS spec:

4.5.3  When dry-annealed finish is specified(see 3.3), water shall be applied to the surface of a specimen having an area of 10 square inches or larger. Dry-annealed foil will support an unbroken water film.
<found at http://everyspec.com/FED_SPECS/Q/QQ-A-1876_5558/>

Regards,

SAE Aerospace Material Specification AMS4011 is for 99.45% pure Aluminum as foil and light gauge sheet.  I have taken on an assignment to review and update, if necessary, the subject document.  It was first issued in 1968 and has had 4 revisions since then.  Unfortunately, I have no access to any prior information on or discussions about it.

This product is used "typically" for capacitors, electronic components, and sound/vibration damping tape but may have other applications.

There are a number of perplexing requirements, however.

The "foil" can have either a dry or slick surface condition, determined by placing drops of a water/alcohol solution and observing its wettability.  It appears that this is determined by observing this behavior with various percentages of the alcohol, but no actual criterion for acceptance is given (nor does it appear to be an attribute to be entered in the procurement document).  Interestingly, the surface is supposed to be "bright" on one side and "matte" on the other, but there is no discussion of which side is supposed to be tested for wettability or "oiliness".

There is a tensile test requirement on the foil per ASTM E354 in addition to a breaking load one for foil between 0.00017 and 0.00050 inch thick. The latter test can be performed on either a single thickness of the very-thin foil or on "specimens consisting of multiple thicknesses of product".  I would think that, if one of those foils failed, when the load is transferred all the rest would almost immediately giving a statistically invalid result.

I have not been successful in determining who makes or uses this product, how it can be successfully and unambiguously tested, and what properties are really important for its use. There's no problem with the light-gauge sheet requirements which seem pretty conventional.

I would appreciate any insight or experience anyone has in the testing ambiguities and practicalities, the (important) uses and properties requirements, and the source(s) of its production.