A recent change to ASTM E18 (published in ASTM E18-14) requires that the calibration certificate for ball indenters and Class B diamond indenters state the Rockwell scale(s) that the indenter is certified to perform (clauses A126.96.36.199 and A188.8.131.52). The intent of this addition was to clearly state the scales that a singular or limited scales indenter is certified to perform. However, it has been brought to the attention of the E28.06 Subcommittee that this could be interpreted in such a way as to invalidate all previously certified regular Rockwell indenters that do not state on the calibration certificate the scale(s) that the indenter is certified to perform. To prevent this problem, this concurrent E28/E28.06 ballot item proposes to revise the applicable E18 clauses such that the certified scale information need only be reported on the calibration certificates of singular or limited scales indenters.
Keywordshardness; mechanical test; metals; Rockwell;
Ballot Item Approved