The CGM-7 is a modern microprocessor based instrument for measuring crack depth in metals undergoing materials testing. Building on the success of the CGM-5R this unit improves upon the CGM-5R specification by offering two channel operation, higher frequency and current outputs, full computer control and a variety of expansion options.
It utilises the alternating current potential drop method (ACPD) which is an established technique covered by the ASTM 647 standard. The technique involves passing an alternating current through the metal under test and measuring the resultant voltage drop that is created across the specimen. The presence of a growing defect will alter this voltage and by suitable calibration, a measure of the defect depth can be obtained.
Write a review
Sharing your experience will help scientists like you. Achieve Reviewer Status and Win an iPad 3 (All reviews published will be entered into the next drawing on January 30th 2014).