Section supervisorcochairman of ASTM Task Group E24.01.06, U.S. Steel Corp., Research Laboratory, Monroeville, PA
Senior materials engineercochairman of ASTM Task Group E24.01.06, Babcock & Wilcox Canada, Cambridge, Ontario
A task group designated ASTM E24.01.06 conducted round robin tests to estabish guidelines for preparing a test specification for rapid-loading plane-strain fracture-toughness testing, KIc( ) (the time of the test from zero to maximum load, in milliseconds, is included in the parentheses). Procedures described in ASTM Test for Plane-Strain Fracture Toughness of Metallic Materials (E 399) were adhered to in the program. KIc( ) tests of A533 Class steel were conducted at −18 (0) and −51°C (−60°F) for loading times as short as about 1 ms using compact tension and bend specimens with 25, 38, and 51 mm (1.0, 1.5, and 2.0 in.) thickness in high-speed closed-loop testing machines and with quasi-impact and impact testing methods.
Although the recommended test procedure will only be for testing specimens with clip gages and will exclude quasi-impact and impact testing, the test results show that additional programs could extend the method to include quasi-impact and impact testing. The round robin test results show that the procedures outlined in the recommendations of this report should give reproducible KIc( ) results consistent with the data scatter expected for fracture toughness testing of temperature- and strain-rate sensitive steels.
Paper ID: JTE10289J