In view of the fracture of laser repaired main shaft of a wind turbine

several tests and analysis methods were carried out for the samples

such as macro inspection

chemical composition analysis

room temperature tensile test

room temperature impact test

brittle transition temperature test

metallographic analysis

cladding size measurement

hardness test and fracture scanning electron microscope analysis. The results show that

the matrix material and deposition quality of the shaft sample were unqualified

and the fracture property of the sample was high cycle fatigue fracture in multi-source areas. These source areas located on the outer wall of the heat affected zone adjacent to the cladding layer. The main cause of the shaft fatigue fracture was the poor performance of the cladding heat affected zone.