湿磨衬板用中铬合金钢ZG25Cr7的研制

Research of Medium Chromium Alloy Steel Liner Under Wet Grinding

为了改善水泥厂湿法棒球原料磨及黑色矿山、有色矿山湿式球磨机衬板材料性能,提高其在受冲击磨料磨损和酸碱腐蚀的条件下的使用寿命,研制了一种中铬多元合金钢(ZG25Cr7)新型耐磨材料。经960℃油淬+240℃回火处理,金相组织为细小回火板条马氏体和极少量残余奥氏体;冲击韧性为173.6J/cm2,硬度为HRC53.5。经过静态腐蚀试验表明,在pH值为4.5的弱酸里,高锰钢(ZGMn13Cr2)的平均腐蚀速度是研制钢种(25Cr7)的15.61倍;硅锰钢的平均腐蚀速度是研制钢种(ZG25Cr7)的2.24倍。说明研制钢种(ZG25Cr7)有良好的耐弱酸腐蚀性能。在pH值为10.5的碱性介质里腐蚀速度也较小,硅锰钢腐蚀速度是研制钢种(ZG25Cr7)的1.96倍,高锰钢(ZGMn13Cr2)是研制钢种的1.19倍。可见研制钢种是一种耐腐蚀,耐冲击的新型耐磨材料。

In order to improve the properties of the wet rod and ball mill liners suffering the abrasive wear from the impacting mill materials in ferrous and nonferrous metal mines, and its service life under the condition of acid and alkaline corrosion from wet limestone raw material millstones in cement factory, a new wear-resistant alloy steel ZG25Cr7 with low carbon medium chromium has been studied. The microstructure of the wear-resistant material consists of both fine tempered lath martensite and a little retained austenite, and its impact toughness and hardness is 173.6 J/cm^2 and HRC 53.5, respectively, after oil-quenched by 960℃ and tempered at 240℃. The static corrosion test shows that in the weak acid of pH 4.5, high manganese steel ZGMn13Cr2 has average corrosion rate of 15.61 times higher than that of this new alloy steel ZG25Cr7, while Si-Mn steel has average corrosion rate of 2.24 times higher than that of this new alloy steel ZG25CrT. The results demonstrated that the alloy steel has excellent weak acid-resistant property. Besides; in the strong alkaline of pH 10.5, the test result shows that above three kinds of steels have less corrosion rates; the average corrosion rate of Si-Mn steel is 1.96 times higher than that of this steel, and high manganese steel is 1.19 times higher than that of this steel. So this steel is a good corrosion-resistant, abrasion-resistant and impact-resistant material.