Transitions between pitting and intergranular corrosion in AA2024

Intergranular pitting corrosion of CoCrMo biomedical implant alloy.

CoCrMo samples of varying microstructure and carbon content were electrochemically corroded in vitro and examined by scanning electron microscopy and electron backscatter diffraction techniques. The rate of corrosion was minimized (80% reduction from icorr = 1396 nA/cm(2) to icorr = 276 nA/cm(2) ) in high-carbon CoCrMo alloys which displayed a coarser grain structure and partially dissolved sec...

Pitting Corrosion Monitoring Using Acoustic Emission

The Correlation between Grain Boundary Character and Intergranular Corrosion Susceptibility of 2124 Aluminum Alloy

The effects of grain boundary character on the intergranular corrosion susceptibility of 2124 aluminum alloy were examined. In the study, the alloy was heat treated at 540oC and corrosion tested according to ASTM G110 standards. After obtaining grain orientations from the automated Electron Back-Scatter Diffraction (EBSD), both grain boundary character and grain boundary plane distributions wer...

Corrosion pitting and environmentally assisted small crack growth.

In many applications, corrosion pits act as precursors to cracking, but qualitative and quantitative prediction of damage evolution has been hampered by lack of insights into the process by which a crack develops from a pit. An overview is given of recent breakthroughs in characterization and understanding of the pit-to-crack transition using advanced three-dimensional imaging techniques such a...

Ultrasonic Detection and Measuring of Isolated or Pitting Corrosion (ipc)

AS2542.3 (Determination of Thickness – Use of Ultrasonic Testing) states: “This standard specifies six methods for determination of thickness of material based on the use of ultrasonic pulse-echo principals where the scanning and reflecting surfaces are substantially parallel”. In many cases, the principals and procedures used in AS2452.3 are not applicable for the detection and measuring of is...