耙吸式挖泥船耙齿的泥浆冲蚀腐蚀磨损机制分析(英文)

Slurry Erosion-Corrosion of Scoop Teeth of Suction Dredgers

在耙吸式挖泥船耙齿工作表面观察到泥浆冲蚀腐蚀磨损现象。耙齿表面承受田砂土、砾石和海水组成的泥浆的冲击。在光学和电子金相显微镜下观察到凹坑和托尾状沟槽以及带有网状裂纹的氧化膜。本文提出了耙齿表面在冲蚀和腐蚀同时作用下而磨耗的模式 ,分析了材料因素对冲蚀腐蚀抗力的影响 ,说明了表面磨损形貌特征的形成过程。并建议在类似于耙齿工作条件下的耐磨材料的选择应注重材料的硬度、韧性、纯度、夹杂物含量及材料在液体介质中的电极电位。同时具有高的硬度和韧性的材料具有较高的冲蚀抗力 。

Slurry erosion corrosion has been observed under practical conditions on the alloy steel teeth of a scoop type suction dredger.The tooth surfaces were attacked by the slurry containing sand,silt and water with a high chloride content.Pits with tail like grooves and oxide films with a network of cracks were observed by macroscopic and microscopic surface examination.A model is proposed for analysing the synergistic effects of erosion and corrosion and the effects of material factors on slurry erosion-corrosion resistance.The processes of formation of the surface features are described.It is suggested that in the selection of materials for use under conditions similar to those of the scoop teeth,attention should be paid to material hardness,toughness,purity and electrical potential of the material in the aqueous medium.Materials with both high hardness and toughness offer high erosion resistance.Materials with low inclusion levels and high electrical potential in the aqueous medium normally exhibit high corrosion resistance.