51CrV4弹簧钢夹杂物及第二相行为规律研究

发布时间：2018-06-09 01:15

  本文选题：51CrV4弹簧钢 + 夹杂物　； 参考：《江西理工大学》2017年硕士论文

【摘要】：随着汽车工业的大力发展,我国在一般强度、高强度弹簧钢生产技术方面已经成熟,获得了很多创新成果,并进行了产业化推广,但针对超高强度、高质量等级弹簧钢的工艺技术方面还没有完全突破,还远未达到产业化水平,仍有很多基础技术,工程化技术需要研究开发。本文对国内某钢厂生产的51CrV4弹簧钢的基础技术进行了相关研究,主要包括典型夹杂物分析研究、第二相析出规律研究和奥氏体动态再结晶规律研究。本论文研究的最终成果是为国内某钢厂高强度优质弹簧扁钢51CrV4的生产提供技术上的支持,以达到整个生产流程的工艺技术提升,研究结果表明:显微夹杂物主要以条形、类球形为主,数量较多,根据对显微夹杂物统计结果,其中10μm以下占绝大多数,显微夹杂物种类主要为部分MnS,少量Al_2O_3夹杂,Al_2O_3-CaOSiO_2复合夹杂物居多。大型夹杂物含量较高,种类主要有CaO类夹杂;Al_2O_3-SiO_2-Cr_2O_3-CaS-FeS复合夹杂物;(Cr、V)_2O_3-SiO_2-FeS复合夹杂物;SiO_2-CaO-Cr_2O_3-Al_2O_3-MgO复合夹杂物;Al_2O_3-SiO_2-TiO复合夹杂物;Al_2O_3夹杂或Al_2O_3-CaO夹杂;Al_2O_3-SiO_2夹杂物和硅酸盐类夹杂;在计算温度范围内的主要析出相有:FCC_A1,MnS,FCC_A1#2,BCC_A2,M_7C_3,DIAMOND_FCC_A4,M_(23)C_6,FCC_A1,M_3C_2。合金元素Cr和V含量的改变对析出相MnS、BCC-A2和FCC-A1几乎没有影响,对析出相FCC-A1#2,M_7C_3和M_3C_2影响较大。其中Cr含量对FCC-A1#2析出相影响不大,开始析出温度,最大析出量和最大析出量时温度,随着V含量的增加而增大;V含量对M_3C_2和M_7C_3析出相相关参数影响不大,最大析出量随着Cr含量的增加而增大,Cr含量对其他相关析出参数影响不大;当其他压缩变形参数一定时,变形温度在800-950℃的工艺条件下,奥氏体平均晶粒直径随着变形温度的增加而减小,在950℃的变形温度下得到的晶粒直径最小,晶粒度最大;在0.01-1 s-1变形速率下,随着应变速率的增加,奥氏体晶粒直径减小;当高于1 s-1的变形速率,奥氏体晶粒直径进一步增大;当其他变形工艺参数一定时,随着应变值的增加,晶粒直径减小,晶粒度增大。
[Abstract]:With the rapid development of automobile industry, our country has matured in general strength, high strength spring steel production technology, obtained many innovative achievements, and carried on the industrialization promotion, but aimed at the ultra high strength, The process technology of high quality grade spring steel has not completely broken through, has not reached the industrialization level, still has many basic technologies, the engineering technology needs to be researched and developed. In this paper, the basic technology of 51CrV4 spring steel produced by a domestic steel factory has been studied, including the analysis of typical inclusions, the precipitation of the second phase and the dynamic recrystallization of austenite. The final achievement of this paper is to provide technical support for the production of high strength and high quality spring flat steel 51CrV4 in a domestic steel plant, so as to improve the process technology of the whole production process. The results show that the microinclusions are mainly strip shape. According to the statistical results of microscopic inclusions, the majority of them are below 10 渭 m, the types of microscopic inclusions are mainly MNS, and a small amount of Al2O3 inclusions include Al2O3-CaOSiO-2 composite inclusions. The main types of large inclusions are: al _ 2O _ 3-SiO _ 2-CaS _ 2O _ 2-SiO _ 2-Al _ 2O _ 3-SiO _ 2-TiO _ 2 composite inclusions, Al2O3-SiO3-SiO2-TiOII, Al2O3-Ca2O3-Ca2O3-CaO / Al _ 2O _ 3-CaO / Al _ 2O _ 3-CaO _ 2O _ 3, Al _ 2O _ 3-CaO _ 2O _ 2 and Al _ 2O _ 3-CaO _ 2O _ 2 inclusions and silicate inclusions; The main precipitating phases in the range of calculation temperatures are: 1 FCCA1MnSCCA1 / FCCA1 / BCCA2 / BCCA2 / M7C3 / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C / C The changes of Cr and V contents have little effect on the precipitated phase MnS+ BCC-A2 and FCC-A1, but have a great effect on the precipitated phase FCC-A1 #2M7CStud3 and M3CSP _ 2. The Cr content has little effect on the precipitating phase of FCC-A1 #2, but the temperature at the beginning of precipitation, the temperature at the maximum amount of precipitation and the maximum amount of precipitate, and the increase of the content of V with the increase of V content have little effect on the parameters of the precipitated phase of M3CStut2 and M7C3. The maximum amount of precipitation increases with the increase of Cr content and has little effect on other related precipitation parameters, and when other compression deformation parameters are fixed, the deformation temperature is between 800 鈩，

本文编号：1998121