Abstract：Multiple chains of slag conveyor broke after been used for about one and a half years in a thermal power plant， which is a premature failure. the causes of chain fracture of slag dredger were analyzed by means of the spectrum， tensile test， microhardness test， metallography examination and scanning electron microscope. The results showed that the failure type of the chain was fatigue fracture. The chain was subjected to transverse stress cracking with multiple fatigue crack sources in the process of operation. The crack originated from the internal oxidation defects of carburizing caused by gas carburization， which was the fundamental cause of the final fracture and failure of the chain of the dredger.
2020, Vol. 38 
