RUST GENERATING ACCELERATOR FOR BOLT JOINT SURFACE

摘要

PURPOSE:To obtain titled accelerator capable of early generation of stabilized red rust, also free from pitting generation, comprising ferric chloride, a specific amount, based on said ferric chloride, of nitric acid (or ferric nitrate) calculated as nitrate ion, and a surface active agent. CONSTITUTION:The objective rust generating accelerator comprising (A) ferric chloride, (B) nitric acid (or ferric nitrate) in an amount corresponding to 20- 100 (pref. 25-100)%, based on said ferric chloride, calculated as nitrate iron, and (C) a surface active agent. The concentration of the ferric chloride and the surface active agent are pref. =0.2% and 0.5-2%, respectively. EFFECT:Red rust generated exhibits extremely high adhesivity to the bare metal surface, having higher coefficient of friction than that of naturally-occurring one. USE:For bridges, steel structures, etc.