Investigation of the Microstructure of Surfaced Layer from Flux-Cored Wire of the Fe - C - Si - Mn - Cr - Ni - Mo - V System

The article presents the results of studies of the structure and non-metallic inclusions of metal surfaced from a flux-cored wire of the Fe - C - Si - Mn - Cr - Ni - Mo - V system. In the composition of the wire charge, instead of amorphous carbon, gas cleaning dust of aluminum production containing carbon and fluorine was introduced. Surfacing from a flux-cored wire with a diameter of 5 mm on plates made of St3 steel under AN-26S flux was carried out using a welding machine at a current of 420 - 520 A, a voltage of 28 - 32 V, a welding rate of 7.2 - 9 m/h with cooling at room temperature. The properties of two samples with different content of the carbon-fluorine-containing additive in a flux-cored wire have been studied. The grain size and martensite dispersion in the structure of the surfaced layer have been determined. The analysis of the chemical composition of the surfaced layer and non-metallic inclusions generated in it has been carried out. The hardness of the samples has been measured by the Rockwell method. It has been concluded that it is necessary to establish the optimal amount of the carbon-fluorine-containing additive in the flux-cored wire in order to avoid the formation of an increased amount of non-metallic inclusions in the surfaced layer.