两种涂层和两种钢在液/固两相流中冲刷与腐蚀的交互作用

用失重法和电化学法系统地研究了20钢基体、两种Ni基涂层(Ni60JH和Delelo50)以及对比材料lCrl8Ni9Ti不锈钢在液／固两相流(5％H2SO4 15％石英砂)中冲刷与腐蚀的交互作用．实验表明：(1)在冲刷速率为5—10m／s时，Ni60JH涂层的耐冲刷腐蚀性能比基体高8—15倍多，并优于1Crl8Ni9Ti不锈钢；DelelO50涂层的耐冲刷腐蚀性能比基体高3—5倍多．(2)随着冲刷速率的提高，4种材料的冲刷腐蚀交互作用失重率在冲刷腐蚀总失重率中所占比例显著增大，由低速时的45％增加到高速时的80％，从而使冲刷腐蚀交互作用失重率在冲刷腐蚀总失重率中占主导地位．(3)在纯腐蚀中，Ni60JH涂层和1Crl8Ni9Ti不锈钢以均匀腐蚀为主要特征，而DelelO50涂层和20钢以选择性腐蚀为主要特征．

SYNERGISTIC EFFECTS BETWEEN EROSION AND CORROSION OF TWO COATINGS AND TWO STEELS IN TWO--PHASE FLOW

The Synergistic effects between erosion and corrosion of two high velocity oxy-fuel (HVOF) Ni-based coatings (Ni60JH and Delelo50) deposited on a low carbon steel in a liquid-solid two-phase flow were systematically investigated by a weight loss test method and an electrochemical method. And a stainless steel was compared to the two coatings and the substrate. The experiment results indicate: (1) At the erosion rate 5-10 m/s, the erosion-corrosion resistance of Ni60JH and Delelo50 coatings was 8-15 times and 3-5 times higher than that of the substrate, respectively. And the erosion-corrosion resistance of Ni60JH coatings slightly exceeded that of the stainless steel. (2) The weight loss rates of the synergistic effects between erosion and corrosion of the four types of materials changed from 45% to 80% of the total weight loss rates with the erosion rate increasing from 5 m/s to 10 m/s. The weight loss rates of the synergistic effects between erosion and corrosion were primary in the total weight loss rates of erosion and corrosion. (3) In the pure corrosion, the main corrosion characteristic of Ni60JH coating and stainless steel was the uniform corrosion, while that of Delelo50 coating and low carbon steel was the selective corrosion.