农机耙片用新型铸态贝氏体钢的组织与耐磨性

Formation and Wear Resistance of a New Cast Bainitic Steel Used in Manufacturing the Harrow Disk

为改进耙片的材质和工艺 ,研制出一种新型铸态贝氏体钢 ,采用液态挤压铸造使耙片一次成形 ,以代替原 6 5 Mn钢及传统生产工艺。该铸态贝氏体钢通过合金化和控制冷却速度的方法 ,不需热处理而在铸态下直接得到贝氏体组织和所需性能。试验结果表明 ,新型铸态贝氏体钢的耐磨性明显优于热处理后 6 5 Mn钢。其洛氏硬度为 4 6～ 5 0 HRC,冲击韧性 ak≥ 2 6 J/cm2 ,对 6 5 Mn钢的相对耐磨系数为 1.2

In order to improve the characteristics of a harrow disk and simplify the process of producing, a new model as cast bainitic steel was studied and produced. We made the disk formed directly by the way of liquid squeezing to replace the 65Mn steel and the traditional manufacturing craftwork. The new bainitic steel formation and its required characteristics were obtained directly in the casting phase without any heat treatment, by the way of alloying and controlled cooling. In order to authentically manifest the forming of a new as cast bainitic formation, the paper simulated the casting phase condition with the CCT diagram and found out the rules of the continuous cooling speed and the forming of all kinds of formations after qualifying the best elements of steel. The experimental result indicates that the wear resistance of the new steel is better than that of the 65Mn heat treated steel. The mechanical properties of the steel are 46～50 HRC and a k ≥26 J/cm 2. The relative abrasive resistance of this steel to 65Mn steel is 1 29. It supplies a new and more promising material for the manufacture of harrow disk.