18Ni马氏体时效钢是近20年才发展起来的新型超高强度钢。其化学成分为Ni17～18%,Co 8～13%,Mo3～5%,Al0.05～0.15%,Ti0.5～2.0%,其余为Fe,(C≤0.03%)。由于这类钢具有较高的比强度和破断韧性,良好的可焊性与成形性,热处理工艺简单和热处理后尺寸变形小,因此被广泛地应用于航空、宇宙飞行、核燃料生产以及工具、模具和机械制造等方面。但是18Ni马氏体钢的耐腐蚀性能不好,在大气中就会产生腐蚀。在水、盐溶液、无机酸和有机酸中腐蚀严重。要使18Ni马氏体时效钢充分 18Ni martensitic aging steel is a new type of ultra-high strength steel developed only in the past 20 years. Its chemical composition is Ni17-18%, Co8-13%, Mo3-5%, Al0.05-0.15%, Ti0.5-2.0%, balance Fe, (C≤0.03%). Due to its high specific strength and fracture toughness, good weldability and formability, simple heat treatment process and small dimensional deformation after heat treatment, it is widely used in aviation, space flight, nuclear fuel production and tools, molds And machinery manufacturing and so on. But 18Ni martensitic steel corrosion resistance is not good, will produce corrosion in the atmosphere. Corrosion is serious in water, salt solution, mineral acids and organic acids. Make 18Ni martensitic steel sufficient