1100MPa级热处理钢轨开发及使用

Development and Application of 1100 MPa Heat-Treated Rail

通过对线路钢轨伤损特点的研究分析,认为开发碳含量相对较低、抗拉强度1 100 MPa级韧性较好的热处理钢轨,在快速客货混运线路上使用有利减少其接触疲劳伤损,提高钢轨综合使用效果。通过钢轨钢成分、热处理工艺与组织性能的研究,开发出了抗拉强度1 080～1 150 MPa、断裂韧性KIC为45～51 MPa.m^1/2,裂纹萌生和扩展速率低于既有钢轨的碳素在线热处理钢轨。钢轨在160 km/h、年运量达7 200万t的客货混运线路上试用,表现出优良的抗接触疲劳伤损性能和较好的耐磨性能,钢轨使用1年后轮轨作用面光亮,未出现接触疲劳裂纹,耐磨性能优于抗拉强度1 000 MPa级U75V热轧钢轨。

By researching and analyzing the damage feature of line rail, the heat-treated rail with lower carbon content, 1 100 MPa tensile strength and better toughness, was thought to be favorable to decrease contact fatigue damage and improve performance in the fast line of transporting both passengers and goods. Through researching the steel composition, heat-treatment structure and properties,a new carbon-containing on line heat-treated rail steel was developed, which tensile Strength is 1080-1150 MPa,KIC is 45-51 MPa · m^1/2, and the crack initiation rate and propagation rate is lower than that of traditional rail steel. The rails had demonstrated good anti-contact-fatigue- damage and better wear-resisting performance after use on a line with train speed of 160 km/h and transportation of 72 000 000 ton a year for a year. The rail working face contacting the wheel was bright and no contact fatigue crack was observed. The wear-resistance of this rail is better that of 1000 MPa rail.