52CrMoV4弹簧扁钢的端淬特性

Jominy end quenching characteristics of 52CrMoV4 leaf spring steel

在大规格52CrMoV4热轧弹簧扁钢上取样,进行端淬试验,研究900℃×1 h的正火预处理和850、900℃的奥氏体化对52CrMoV4钢端淬性能的影响。结果表明,热轧扁钢在850℃端淬后,淬火硬度较低,端淬硬度曲线波动较大,带状组织明显,该温度端淬在一定程度上反映了钢材成分均匀程度。热轧扁钢在900℃端淬后能够获得更高的硬度。端淬前的正火处理能使整体硬度得到提升,但其提升效果不如提高淬火温度明显。52CrMoV4钢板簧生产中,采用900℃淬火能稳定获得60 HRC左右的高硬度,提升钢板弹簧的淬火工艺性。

Jominy end quenching test were carried out on 52CrMoV4 large specification leaf spring steel to investigate the effects of normalizing pretreatment at 900℃for 1 h and austenitizing at 850℃and 900℃on Jominy end quenching characteristic of the 52CrMoV4 leaf spring steel.The results show that the end⁃quenching hardness of hot⁃rolled steel after austenitizing at 850℃is lower and banded microstructure is more obvious and the end⁃quenching curve fluctuates greatly,which can reflect the uniformity of chemical composition distribution to some degree.Hot⁃rolled steel austenitized at 900℃can reach higher hardness and normalizing before quenching can stabilize the overall hardness of 52CrMoV4 leaf spring steel.During 52CrMoV4 steel leaf spring manufacturing process,900℃austenitizing temperature is adopted to acquire higher hardness around 60 HRC,displaying better quenching properties.