In the first half of 2007 ASTM Subcommittee E28.06 passed new versions of E18 for Rockwell testing. These new documents took several years to finish and are complete rewrites of the popular test method. There are many technical changes and new document requirements that can have a far reaching effect, especially when you have to satisfy the needs of an auditor. It may be that none of your Rockwell test results meet the new standards.
Rockwell Test Blocks:
E18-07 and later test methods require that Rockwell Test Blocks be calibrated with Class A indenters using extended test times. This makes all pre E18-07 Rockwell test blocks obsolete and in order to be compliant with the new standard either new E18-07 or later test blocks need to be obtained or older non-compliant test blocks can be recalibrated.
Rockwell Diamond Indenters:
E18-07 and later test methods require that Rockwell Test diamond indenters are to be geometrically verified. The indenter performance requirements have been tightened and now all diamond scale indenters are traceable to the National Institute of Standards and Technology (NIST). These changes make all pre E18-07 indenters obsolete. In order to comply with the latest standard you can obtain new test blocks that comply with the standard or you can send your old indenters to the Wilson Calibration Laboratory for recalibration.
Rockwell Ball Indenters:
E18-07 and later test methods add performance verification as a new requirement. Previous ASTM test methods did not require manufacturers to verify the performance of ball penetrators. The reasoning for adding a performance requirement in the standard was to ensure the performance of ball penetrators. The impact of this change makes all pre E18-07 ball indenters obsolete and new ball penetrators need to be purchased to be in compliance with the latest ASTM test methods.
Rockwell Testers:
With all of the above changes to test blocks and indenters your Rockwell tester will need to be reverified to E18-07 or later to ensure compliant test results.