CAJ | 학술논문

使用光学显微镜、扫描电镜和能谱仪等研究了钎具用钢22Si2MnCrNi2MoA 动态连续冷却相变规律和退火工艺优化,分析了冷却速度对连续冷却转变曲线和相变组织的影响,探讨了22Si2MnCrNi2MoA 钢带状组织成因及改善措施.22Si2MnCrNi2MoA 钢具有较高的淬透性,在形变后空冷即可得到贝氏体+马氏体组织.在所选取的温度和时间范围内,710℃退火保温5 h 为最优的退火工艺,等温退火并不能改善钢中带状组织的成分不均.带状组织的形成是由于化学元素 Si、Mn、Cr、Ni 和 Mo 的偏聚引起的,提高横截面内变形均匀程度对于改善棒材组织均匀性是有利的,但冶金过程成分偏析均质控制才是减轻或消除带状组织成分不均的关键.
사용광학현미경、소묘전경화능보의등연구료천구용강22Si2MnCrNi2MoA 동태련속냉각상변규률화퇴화공예우화,분석료냉각속도대련속냉각전변곡선화상변조직적영향,탐토료22Si2MnCrNi2MoA 강대상조직성인급개선조시.22Si2MnCrNi2MoA 강구유교고적쉬투성,재형변후공랭즉가득도패씨체+마씨체조직.재소선취적온도화시간범위내,710℃퇴화보온5 h 위최우적퇴화공예,등온퇴화병불능개선강중대상조직적성분불균.대상조직적형성시유우화학원소 Si、Mn、Cr、Ni 화 Mo 적편취인기적,제고횡절면내변형균균정도대우개선봉재조직균균성시유리적,단야금과정성분편석균질공제재시감경혹소제대상조직성분불균적관건.
@@@@22Si2MnCrNi2MoA drill steel was tested by optical microscopy, scanning electron microscopy and energy dispersive spectroscopy to study its dynamic continuous cooling phase transformation law and annealing process optimization, analyze the effect of cooling rate on its continuous cooling transformation (CCT) curves and transformation microstructure, and find out the cause of banded structure formation and measures for quality improvement. It is shown that the steel has high hardenability, and a bainite and martensite duplex microstructure is obtained when the hot rolled material is cooled in air after deformation. The optimal annealing process is at 710 ℃ for 5 h. The composition inhomogeneity of the banded structure in the steel cannot be eliminated by isothermal annealing. The banded structure is caused by the segregation of the alloy elements of Si, Mn, Cr, Ni and Mo, and can be weakened by improving the cross-section deformation uniformity of bars. However, the homogeneous distribution of alloy elements in the metallurgical process is the critical way to reduce or eliminate the composition inhomogeneity of the banded structure.