Effect of electrical pulse treatment on the thermal fatigue resistance of bionic compacted graphite cast iron processed in water

In order to further enhance the thermal fatigue resistance of bionic compacted graphite cast iron (CGI) which is processed by laser in water, the electrical pulse treatment is applied to improve the thermal fatigue resistance of bionic units. The results show that the electrical pulse treatment causes the supersaturated carbon atoms located in the lattice of austenite to react with the iron atoms to form the Fe3C. The microstructures of the bionic units processed in water are refined by the electrical pulse treatment. The cracks on the bionic units are reduced by the electrical pulse treatment before the thermal fatigue tests; and during the tests, the thermal fatigue resistance of bionic units is therefore enhanced by reducing the crack sources. By this way, the thermal fatigue resistance of bionic CGI processed in water is improved.

► Electrical pulse treatment can reduce cracks on bionic units before thermal fatigue tests.
► Electrical pulse treatment can reduce crack sources during thermal fatigue tests.
► Thermal fatigue resistance of bionic units processed in water is enhanced.
► Thermal fatigue resistance of bionic CGI processed in water is improved.