Effects of silicon （Si） content on the stability of retained austenite and temper embrittlement of ultrahigh strength steels were investigated using X-ray diffraction （XRD）,transmission electron microscopy （TEM）...Effects of silicon （Si） content on the stability of retained austenite and temper embrittlement of ultrahigh strength steels were investigated using X-ray diffraction （XRD）,transmission electron microscopy （TEM）,and other experimental methods.The results show that Si can suppress temper embrittlement,improve temper resistance,and hinder the decomposition of retained austenite.Reversed austenite appears gradually with the increase of Si content during tempering.Si has a significant effect on enhancing carbon （C） partitioning and improving the stability of retained austenite.Si and C atoms are mutually exclusive in lath bainite,while they attract each other in austenite.ε-carbides are found in 1.8wt% Si steel tempered at 250℃,and they get coarsened obviously when tempered at 400℃,leading to temper embrittlement.Not ε-carbides but acicular or lath carbides lead to temper embrittlement in 0.4wt% Si steel,which can be inferred as cementites and composite compounds.Temper embrittlement is closely related to the decomposition of retained austenite and the formation of reversed austenite.展开更多
为考察热处理工艺对材料性能的影响,对不同回火温度下三种碳含量的30Cr Mn Si Ni2A钢的性能进行实验研究,并分析其组织和断口形貌.研究结果表明:低温回火时30Cr Mn Si Ni2A钢具有较高的强度和硬度,其内部组织为回火马氏体,断口形貌为韧...为考察热处理工艺对材料性能的影响,对不同回火温度下三种碳含量的30Cr Mn Si Ni2A钢的性能进行实验研究,并分析其组织和断口形貌.研究结果表明:低温回火时30Cr Mn Si Ni2A钢具有较高的强度和硬度,其内部组织为回火马氏体,断口形貌为韧窝断口;当碳含量增大,30Cr Mn Si Ni2A钢的强度也增大;随着回火温度升高,30Cr Mn Si Ni2A钢的强度和硬度逐渐下降,伸长率和断面收缩率却总体呈上升趋势,其组织向索氏体转变,断口形貌变为解理和沿晶断口,回火脆性与其内部形核有关.展开更多
基金supported by the Project of Scientific and Technical Supporting Program of China during the 11th Five-Year Plan(No.2006BAE03A06)
文摘Effects of silicon （Si） content on the stability of retained austenite and temper embrittlement of ultrahigh strength steels were investigated using X-ray diffraction （XRD）,transmission electron microscopy （TEM）,and other experimental methods.The results show that Si can suppress temper embrittlement,improve temper resistance,and hinder the decomposition of retained austenite.Reversed austenite appears gradually with the increase of Si content during tempering.Si has a significant effect on enhancing carbon （C） partitioning and improving the stability of retained austenite.Si and C atoms are mutually exclusive in lath bainite,while they attract each other in austenite.ε-carbides are found in 1.8wt% Si steel tempered at 250℃,and they get coarsened obviously when tempered at 400℃,leading to temper embrittlement.Not ε-carbides but acicular or lath carbides lead to temper embrittlement in 0.4wt% Si steel,which can be inferred as cementites and composite compounds.Temper embrittlement is closely related to the decomposition of retained austenite and the formation of reversed austenite.
文摘为考察热处理工艺对材料性能的影响,对不同回火温度下三种碳含量的30Cr Mn Si Ni2A钢的性能进行实验研究,并分析其组织和断口形貌.研究结果表明:低温回火时30Cr Mn Si Ni2A钢具有较高的强度和硬度,其内部组织为回火马氏体,断口形貌为韧窝断口;当碳含量增大,30Cr Mn Si Ni2A钢的强度也增大;随着回火温度升高,30Cr Mn Si Ni2A钢的强度和硬度逐渐下降,伸长率和断面收缩率却总体呈上升趋势,其组织向索氏体转变,断口形貌变为解理和沿晶断口,回火脆性与其内部形核有关.
