This case study deals with the existence of excessive porosity in the welds of an air compressor rotor duct. The duct does not meet the testing criteria because the diameters of the pores in the weld exceeded allowable specifications. As such, the duct failed inspection for excessive pore diameter and shrinkage due to welding. At this point, the part was beyond repair, and it was scrapped. The possible causes of failure were analyzed, and it was concluded that the source of the problem was the welding technique.
S. Roberts, L. Pate, R. Hoang, J. Foyos, R. Nishimuro and O. Es-Said, “On the Excessive Porosity in the Welds of AMS 4975 Titanium, Air Compressor Rotor Duct”, J. of Communications in Reliability, Maintainability and Supportability, Vol. 3(2), 1996, pp. 73-78.