Rechnergestuetztes Pruefverfahren fuer Spannungsrisskorrosionsuntersuchungen (Computer Aided Testing Procedure for Stress Corrosion Cracking Investigations)

摘要

A tensile-test machine was developed in order to transfer the principle of slow-strain-rate tests to fracture mechanics tests. Compact-tensile specimens with a fatigue crack were monotonically tensile-loaded at different, constant drawing rates, in different media. In contrast with the usual fracture mechanics tests, the drawing rates were substantially lower (as low as 0.1 microm/hr). The test equipment, control system, and data acquisition and evaluation are described. The parameters determining the stress corrosion cracking of the system Al2024 T351 in a 3.5 percent NaCl solution were characterized. The method also provides the effective crack resistance curve at the occurrence of stress corrosion cracking. A disadvantage of the procedure is that it requires a relatively large experimental effort.