Epoxy Based Conductive Anti-corrosion Coatings for Grounding Grid

Abstract

Epoxy based conductive anti-corrosion coatings were prepared on the surface of grounding grid Q235 carbon steel with graphite, carbon fiber andaluminum tripolyphosphateas pigments. The influence of the pigment/binder ratio (PBR) on the properties of the coatings was investigated such as the morphology and the electric conductivity of the coatings as well the corrosion behavior of Q235 carbon steel coated by coatings with an optimal PBR by immersion in salt solutions and burying in a selected soil from Shenyang test site. The results indicated that after buried in the soil, the bare Q235 steel suffered from serious corrosion and bubbles occurred on the E44 lacquer coating on the steel, in the contrast, the coatings with the optimal PBR showed excellent protectiveness for the steel even after buried for up to 1000 h in the soil. The volume resistivity and surface contact resistivity of the coatings are 0.65 Ω·cm and 8.72 Ω/cm respectively. The coatings exhibited excellent with standing capacity to high current impulse, such as their electrical resistance decreased by 5.95% and 11.09% for the ones suffered from a high current impulse of 1 kA for 20 times and a power frequency current of 10 A for 5 times respectively, while the surface of the coatings maintained unchanged without any destruction. 定稿日期:2015-03-26 作者简介:刘世念,男,1972年生,高级工程师 通讯作者:王成,E-mail:wangcheng@imr.ac.cn,研究方向为金属腐蚀与防护 DOI:10.11902/1005.4537.2014.273