高承载曲轴用34CrNiMo6钢调质处理工艺强韧化机理研究
Study on Strengthening and Toughening Mechanism of 34CrNiMo6 Steel for High Load Crankshaft by Quenching and Tempering Process
谢波 1李秋睿 2纪超 3王红霞 2赵勇 3路拥庆 3林媛4
作者信息
- 1. 太原理工大学 材料科学与工程学院,山西 太原 030024;山西柴油机工业有限责任公司,山西 大同 037036
- 2. 太原理工大学 材料科学与工程学院,山西 太原 030024
- 3. 山西柴油机工业有限责任公司,山西 大同 037036
- 4. 太原理工大学 材料科学与工程学院,山西 太原 030024;太钢不锈钢股份有限公司技术中心,山西 太原 030003
- 折叠
摘要
针对高承载曲轴需要高强塑性匹配的要求,选用 34CrNiMo6 钢并进行调质热处理,研究淬、回火温度对合金钢力学性能的影响规律,建立工艺-组织-性能的匹配关系,揭示合金钢调质热处理后强韧化机理.得出结论为:回火温度一定时,随着淬火温度升高,34CrNiMo6 钢硬度、强度是逐渐小幅下降,伸长率先增加后减少,并在 860℃时达到峰值,冲击功则逐渐增加.淬火温度一定时,随回火温度增加,硬度、抗拉强度和屈服强度呈现出先降低后增加最后又降低的趋势,伸长率和冲击功呈现出先增加后减小的抛物线形态.在 580℃回火,硬度、强度达到小高峰,伸长率获得最大值,冲击功比 560℃时的最大值略有下降.当回火温度超过 600℃时,各项性能急剧下降.因此,34CrNiMo6 钢的最佳调质工艺为:860℃淬火+580℃回火,其强韧化机理与索氏体的细化程度和残余奥氏体含量及变形过程组织中的位错密度有关.
Abstract
In order to meet the requirements of high strength plasticity matching for high load bearing crankshaft,34CrNiMo6 steel was selected for quenching and tempering heat treatment,and the influence of quenching temperature and tempering temperature on the mechanical properties of alloy steel was studied.The matching relationship between process,structure and properties was established,and the strengthening and toughening mechanism of the alloy steel after quenching and tempering heat treatment was revealed.It is concluded that the hardness and strength of 34CrNiMo6 steel gradually decrease with the increase of quenching temperature when tempering temperature is constant,and the elongation increases first and then decreases,reaching the peak value at 860℃,while the impact energy increases gradually.When the quenching temperature is constant,with the increase of tempering temperature,the hardness,tensile strength and yield strength show a trend of decreasing first before increasing and last decreasing,and the elongation and impact energy show a parabolic shape that increases first and then decreases.At 580℃tempering,the hardness and strength reach small peaks,the elongation obtains the maximum value,the impact energy than that of the maximum of 560℃decreases slightly.When the tempering temperature exceeds 600℃,the performance decreases sharply.Therefore,the optimal quenching and tempering process of 34CrNiMo6 steel is as follows:quenching at 860℃+tempering at 580℃.The strengthening and toughening mechanism of 34CrNiMo6 steel is related to the refinement degree of sorbite,residual austenite content and dislocation density in the microstructure during deformation.
关键词
34CrNiMo6钢/调质/强韧化机理/位错密度/曲轴Key words
34CrNiMo6 steel/quenching and temper-ing/strengthening and toughening mechanism/dislocation density/crank shaft引用本文复制引用
基金项目
山西省科技重大专项项目(20191102004)
山西省自然科学基金项目(202101D121045)
出版年
2024
NETL
NSTL
万方数据