中高碳钢珠光体球团尺寸的快速精确统计方法

研究了显示中高碳钢珠光体球团界的多种试验方法。结果表明:金相腐蚀方法能快速显示出珠光体球团界;电子背散射技术(EBSD)方法显示出的晶界较为复杂,不能精确统计珠光体球团尺寸。在中高碳车轮钢中,应用此金相腐蚀方法,充分显示出了珠光体球团界,且界线清晰,可以保证进行精确定量统计。统计结果表明,珠光体球团尺寸大小与生产工艺有关,球团尺寸减小,韧性提高。此金相腐蚀方法可以应用在其它中高碳珠光体钢中,而不需对腐蚀方法进行较大调整。

Fast and precise determination of pearlite colony size in medium-high carbon steels

Pearlite colony boundaries in medium-high carbon steels were revealed by means of electron backscatter diffraction(EBSD),scanning electron microscopy(SEM) and metallographic technique.The results show that the metallographic technique can permit the preferential etching of pearlite colony boundaries,however,EBSD investigation does not allow precise determination of the mean colony size since the boundary network revealed by EBSD is more complex than the concept of pearlite colonies.Pearlite colony boundaries are definitely revealed and sufficient for accurately quantitative assessment after applying the metallographic technique to a 0.70C railway wheel steel.The assessment result shows that pearlite colony size changes with production process and toughness of the steel increases with refinement of colony size.The metallographic technique could be used in other kind of medium-high carbon pearlitic steels without essential adjusting.