Cr/C比对中铬铸铁复合抗磨辊圈组织和耐磨性的影响

中铬铸铁复合抗磨辊圈服役过程中,外层中铬铸铁层起主要的抗磨和粉碎物料的作用。本文主要研究了Cr/C比对中铬铸铁组织、力学性能和耐磨性的影响。研究结果表明,Cr/C比的不同会影响碳化物的形态和数量,Cr/C比(3.17)较高时,碳化物主要为菊花状和弥散分布的块状的(Cr, Fe)_7C_3,碳化物面积占比为8.90%,冲击韧度为8.6 J,硬度为52 HRC;Cr/C比(2.66)较低时,碳化物主要为网状的(Fe, Cr)_3C和板条状的(Cr, Fe)_7C_3,碳化物面积占比为13.31%,冲击韧度为5.3 J,硬度为56 HRC。且Cr/C比高时,由于具有较高的韧性,可以缓解磨损过程中应力集中,延迟磨屑的剥落,具有更高的耐磨性。

Effect of the Cr/C on Microstructure and Wear Resistance of Medium Chromium Cast Iron Compound Wear-resistant Roll Ring

The outer layer of medium chromium cast iron plays the main role of wear resistant and crush materials in the service process of the medium chromium cast iron compound wear-resistant roll ring. The effect of Cr/C on the microstructure, mechanical properties and wear resistance of medium chromium cast iron were studied. The results show that the form and quantity of carbides are affected by the difference of Cr/C. When the ratio of Cr/C is higher(3.17), the carbides are mainly composed of the(Cr, Fe)7C3which like chrysanthemum and dispersive bulk, the area ratio of carbides is 8.90%, the impact toughness is 8.6 J and the hardness is 52 HRC;when the ratio of Cr/C is lower(2.66), the carbides are mainly composed of the(Fe, Cr)3C like nets and the(Cr, Fe)7C3lath-shaped, the area ratio of carbides is 13.31%, the impact toughness is 5.3 J and the hardness is 56 HRC. When the Cr/C is higher, the abrasive wear resistance is better. It can relieve stress concentration during wear process and delay the spalling of debris because of its high toughness.