Research Report RR:G01-1024
G69 test method was originally published as a technical paper in 1941 and has been in continuous use since as a rapid and simple method to determine the solid solution content of certain alloying elements in aluminum alloys and primarily heat-treatable alloys. A series of inter-laboratory tests were begun in 1976 to measure the solution potentials of aluminum alloys. The purpose of these tests was: 1) to determine if the procedure was sufficiently reproducible to allow it to be written as a standard test method and 2) to determine whether alternative pretreatment methods were acceptable. These tests continued through 1986. A standard practice was approved in 1981, using the time honored mechanical abrasion with dry #320 grade aluminum oxide followed by polishing with #00 steel wool. A negative in 1981 was resolved with the proviso that a round robin test program be conducted to determine whether chemical pretreatments could be used instead of the laborious mechanical pretreatment. A previous research report, G01-1015, was prepared using the data from the ILS, but it failed to incorporate the results for four of the alloys and the calculations were in error. This report presents the results of all of these tests, including the 1976 data that was used to support the G69-81 standard, and round robin testing conducted in 1983, 1985 and 1986 on chemical pretreatments.
G69-20 Standard Test Method for Measurement of Corrosion Potentials of Aluminum Alloys
Committee G01 on Corrosion of Metals
Subcommittee G01.11 on Electrochemical Measurements in Corrosion Testing