Reasons Analysis on Cracking of Flange

The cracking causes of flange of a weld part were analyzed by using direct reading spectrometer, optical microscope, scanning electron microscope (SEM) and energy diffraction spectrometer (EDS) to analyze the chemical compositions, mechanical properties, microstructure and fracture of the flange. The results show that there were a lot of titanium nitride inclusions distributing in cluster and cumulate shape in material of the flange, and the cracks started from these inclusions because of stress concentration during machining process.