WC-Co hardmetals are used for their combined high hardness and toughness. However, their poor corrosion resistance in aqueous solutions reduces the spectrum of their application. The hardness and wear resistance of WC-FeAl-B composites are much higher than WC-Co hardmetals and their toughness is comparable to toughness of WC-Co composites. The goal of thesis was a systematic investigation of the corrosion mechanisms of the WC-FeAl-B composites with electrochemical methods and analytical chemistry solution analysis characterization. WC-FeAl-B and FeAl-B were investigated by electrochemical impedance spectroscopy, potentiodynamic polarization and inductively coupled plasma spectroscopy (ICP). The solution pH dominates the effect of specific ions. In neutral and acidic solution, the corrosion process of WC-FeAl-B composites consists mainly of binder phase dissolution. At alkaline pH WC dissolution becomes more significant. Synergistic effects due to galvanic coupling between the FeAl-B binder and WC are accelerating binder dissolution and hindering WC dissolution in the composites comparing to the pure compounds.