Effect of additives on corrosive wear of carbon steel

Abstract

The effect of additives on the tribological behaviour of 1045 steel in NaCl and H 2SO 4 solution was Investigated. Four substances (K 2Cr 2O 7, sodium dodecyl benzene sulphonate (SDBS), (CH 2) 6N 4 and IMC-5) were used in both solutions as additives to control the corrosive wear loss of specimen. A pin-on-ring wear apparatus and a rotating scratching device with a speed regulator were designed and manufactured for the investigation of steady and transient corrosive wear process. The dependences of friction coefficient and wear loss of specimen vs. load and speed in both aggressive media with or without additives were determined and the morphology of wear tracks was observed by scanning electron microscopy. In order to explain the effect of additives on corrosive wear, the re-formation rate of the passive film and the effect of additives on polarization curves were also determined for the same testing condition. The results show that the roles of additives in corrosive wear can be divided into three types in reducing material removal: 1. (a) as the lubricating additive in a heavy duty and mild corrosive medium (SDBS); 2. (b) as the corrosive inhibitor in a low duty and severe aggressive medium (K 2Cr 2O 7 and (CH 2) 6N 4); 3. (c) as the corrosive wear inhibitor in serious situations (IMC-5).