Summary for aluminum extrusion imperfections Discussion
The phrase "imperfections" is the key issue in this 6061-T6/T6511 extrusion question, because the requester needs to know what visible-surface defects are actually disallowed beyond die marks. Yolanda Craft explains that, aside from FED-STD-245/ANSI-H35.2, she could not find a specific specification that clearly defines imperfections for this material and asks whether the term includes voids, coloration, or inclusions. Brian Terry’s practical advice is to go back to the customer and ask for their own definition or interpretation, since cosmetic acceptability can vary widely and what one person accepts may not satisfy another. The thread does not settle on a universal aluminum-extrusion standard for the term; instead, it emphasizes that the controlling requirement should come from the customer or contract when the wording is vague, especially in aerospace work where cosmetic expectations are strict.
July 11, 2013
Material AL ALLOY 6061-T6/T6511; regarding: visible surfaces must be free of die marks and other imperfections. Aside from FED-STD-245/ANSI-H35.2, what specific specification apply to this material when an extrusion. Imperfections, what spec is there to apply or define imperfections for this material? Die marks are defined but imperfections is too vague. Does it mean, voids, coloration, inclusions?
The area of aerospace is highly critical cosmetically as are functional properties.
Yolanda Craft
aerospace – Santa Maria, California USA
A. Hi Yolanda,
I think you need to go back to your specific customer and see if they have a definition or someone from the customer could give you an interpretation of what is meant.
It is difficult for the rest of us to advise, because what is acceptable to me may not be acceptable to say Ted or James or any of the other regular contributors.
Brian Terry
Aerospace – Yeovil, Somerset, UK