Accelerated Descaling and Polishing of Ferritic Stainless Steel during the HCl-based Pickling Process
The mixtures of nitric acid and hydrofluoric acids are typically utilized for the pickling process of stainless steel.However,with the increasing environmental and safety consciousness due to nitrates and nitrogen oxides(NOx),the use of the mixed acids,especially the nitric acid,has been recently questioned.In this study,the mixtures of hydrochloric acid and oxidant were employed as the environmental friendly pickling solution for ferritic stainless steel.In hydrochloric acid solution,both Ecorr and icorr of stainless steel increases with the elevation of HCl contents which is beneficial for improving pickling efficiency.However,the oxide scales cannot be removed completely via increasing HCl concentration solely and the intergaranular corrosion of base metal aggravates accordingly.Addition of oxidant can boost the corrosion potential of stainless steel significantly and change the electrode action resulting in desired descaling efficiency.At high oxidant content(0.6mol/L),a corrosion product film accumulates onto the surface and the corrosion is then governed by the mass-transport at the film/stainless steel interface.The random dissolving of metal ions because of the film leads to polishing of stainless steel surface and the local corrosion is suppressed.Under the experimental condition,the designed HCl-based pickling solution achieved accelerated descaling and polishing of ferritic stainless steel.
oxidant pickling corrosion rate anodic polishing
Yue Yingying Liu Chengjun Shi Peiyang Jiang Maofa
Key Laboratory for Ecological Metallurgy of Multimetalllic Ores(Ministry of Education),Northeastern University,Shenyang,China
国内会议
上海
英文
1-5
2015-10-21（万方平台首次上网日期，不代表论文的发表时间）