超硬合金と鉄鋼材料と電位差腐食の研究

概要

論文の詳細を見る
In the case of applying cemented carbides to mechanical seal rings or baring parts in pump, the cemented carbides sometimes corrode faster than the expected corrosion rate from the individual corrosion test. It is considered that the galvanic corrosion occurs between cemented carbides and steels as assembled parts. In this reports, the coupled cemented carbides (WC-Co, WC-Ni-Cr3C2, WC-TiC-TaC) and steels (carbon steel and stainless steels) were immersed in both 3%NaCl and 3%NaCl+0.1NH2SO4 aqueous solutions. And their electrochemical corrosive behavior were evaluated by measuring the change of electrode potentials and the current density. As the results, in the case of WC-Co coupled with stainless steels, WC-Co acted as anode being dissolved in either solution. On the other hand, the potential differences were small and the current hardly flowed between WC-Ni-Cr3C2 or WC-TiC-TaC and stainless steels. It was considered that the galvanic corrosion scarcely occurred in these cases.