Diagnostics of Fatigue Failures of Internal Combustion Engine Crankshafts. Part 3. Manufacturing (Processing) Defects as the Cause of Fatigue Failure of Internal Combustion Engine Crankshafts

The third part of the article series devoted to the topic of “Diagnostics of fatigue failures of internal combustion engine crankshafts” shows an example of diagnostics of a fractured vehicle ICE crankshaft with high mileage. The mechanism of fatigue failure of the crankshaft is studied using optical, scanning electron microscopy and various instrumental methods. As the study showed, the cause of the failure of the ICE crankshaft of a passenger car was the design feature of the internal oil channel and the use of reinforcing steel with a high sulfur content. Such defects are classified as manufacturing (processing) defects. The article shows that the use of a wide range of equipment and metallographic studies in the diagnostics of fractured parts allows for a more complete and comprehensive study and the establishment of the real cause of the part or unit failure.