In December 2017, SAE released an updated and much-needed version of AMS 4928. Before we dig into some major changes in AMS 4928W, let’s take a look at where AMS 4928V left off.
AMS 4928 is a specification for titanium bar, wire, forgings, flash-welded rings, and drawn shapes. AMS 4928 is specific to the 6AL-4V alloy.
AMS 4928V covered products up to 6” in diameter or least distance between parallel sides. However, it is commonly requested for products larger than 6” to be certified to AMS 4928. Since larger sizes were not specifically covered in the specification, AMS 4928V left it up to the purchaser and producer to determine what mechanical requirements could be satisfied for any products outside of the range identified in the specification. Usually manufacturers interpreted this as either (1) product manufactured in a size outside of the range of AMS 4928V would be manufactured to meet the properties of the largest size that is covered, or (2) since there are no specific requirements for products outside of the range of the specification, test results would be for information only, and not cause for rejection.
AMS 4928W recognizes that purchasers and end users are looking for assurances of what mechanical properties can be achieved in larger section sizes, by extending the coverage to 10” in diameter or least distance between parallel sides. This allows titanium AMS 4928W products in this extended range to be certified without a “for information only” caveat; we now have firm requirements. For products larger than 10” diameter or least distance between parallel sides, the spec still does mandate the purchaser and producer to agree on the properties. [Read more…]