Rationale

Section 5.5.3 has a mandatory provision that small diameter cylindrical specimen be supported using a v-anvil and thus have hardness tested on a convex surface. Testing on a convex surface is problematic and the issues involved are already outlined within E18 Sections 6.4, 6.5, 9.5 and Tables A6 Note A. As a foundational hardness testing specification, E18 should not have mandatory provisions that are known to be problematic or less accurate than suitable alternatives. Work item removes the mandatory aspect of Section 5.5.3 based on specimen geometry alone which allows users to choose other support methods for those types of specimen. Work item maintains guidance for the use of a v-anvil or similar support should a user choose to test on the convex. This guidance is similar in nature to the other sections addressing specimen support, which do not include mandatory provisions for a specific type of specimen geometry. Further clarification is also proposed regarding section 6.5 as it pertains to 5.5.3. In response to negatives received identifying 6.5 as “non-normative”, 6.5 has been updated to a Note (Note 8) with some modified verbiage to align 5.5.3 and Note 8. The “clamped” requirement in 5.5.3 was identified as being confusing by the committee at May 2024’s meeting so its removal is proposed.