THE EFFECT OF CASTING PARAMETERS ON THE MICROSTRUCTURE AND CORROSION BEHAVIOR OF SAE 430B ALLOYS FOR TRANSPORTATION INDUSTRY

SAE 430B is a Cu-based alloy, which, due to good properties qualify the alloy in special bronzes category. In this paper, the influence of the casting parameters on the properties of the SAE 430B cast in two types of moulds: (i) temporary (based on quartos sand) and (ii) permanent (metallic mould). Samples in as-cast condition were cut and prepared for chemical and microstructural analysis. The chemical composition was determined via spectroscopic analysis, the structural characterization was carried out by optical and electronic microscopy. EDS chemical analysis was used to identify the compositions of phases and compounds in the material. The corrosion behaviour was analysed in seawater by a linear potentiodynamic polarization test. The microstructure of as-cast samples presents a β phase structure with intermetallic precipitates with various morphologies. With the increase in cooling rate, corrosion potential values become more negative and current density increases.