奈米界面析出物強化雙相鋼之顯微組織及機械性質研究

蔡劭璞

doi:10.6342/NTU201704503

山西大学，您好！

感谢采购，人社期刊库｜人社论文库，期间：2025/01/01~2025/12/31

感谢试用，科学期刊库｜科学论文库，期间：2024/10/20~2025/01/20

浏览高级检索

关闭
检索检索高级检索出版物检索
浏览期刊主题浏览核心期刊浏览期刊拼音浏览

关闭

查询符号(半角)	查询符号意义说明
空格	表示为「AND」两个查询词之交集
双引号 ( " " )	片语以双引号标示开始及结束，而且只寻找出现顺序相同的字词，例： " image process "
?	表示一个字母切截，输入两个?表两个字母，依此类推，例：输入「Appl?」，查得结果应为appl e , appl y … ( 常用于英文字查询 )
*	表示不限字母切截，由0~n. 例：输入「appl*」，查得结果应为appl e , appl es , appl y , appl ied , appl ication … ( 常用于英文字查询 )
AND、OR、NOT	布尔逻辑组合关键字，用来扩大或缩小查询范围的技巧。 (1) AND ：缩小查询范围 (2) OR ：扩大查询范围(3) NOT：排除不相关的范围

DOI 是数位物件识别码（ D igital O bject I dentifier ）的简称，
为物件在网路上的唯一识别码，可用于永久连结并引用目标物件。

使用DOI作为永久连结

每个DOI号前面加上「 http://dx.doi.org/ 」便成为永久网址。
如以DOI号为 10.5297/ser.1201.002 的文献为例，此文献的永久连结便是： http://dx.doi.org/ 10.5297/ser.1201.002 。
日后不论出版单位如何更动此文献位置，永久连结所指向的位置皆会即时更新，不再错失重要的研究。

引用含有DOI的文献

有DOI的文献在引用时皆应同时引用DOI。若使用APA、Chicago以外未规范DOI的引用格式，可引用DOI永久连结。

DOI可强化引用精确性、增强学术圈连结，并给予使用者跨平台的良好使用经验，目前在全世界已有超过五千万个对象申请DOI。如想对DOI的使用与概念有进一步了解，请参考（）。

书目管理工具

相关连结

问题回报

全文下载

奈米界面析出物强化双相钢之显微组织及机械性质研究

Investigation on Microstructure and Mechanical Properties of Nanometer-Sized Interphase Precipitation Strengthened Dual-Phase Steels

蔡劭璞 , 博士　　导师：杨哲人　　

英文 DOI： 10.6342/NTU201704503

奈米级界面析出物；双相钢； (扫描)穿透式电子显微镜； Gleeble ；热膨胀仪； nanometer-sized interphase precipitation ； dual-phase steels ； (scanning) transmission electron microscopy ((S)TEM) ； Gleeble ； dilatometer

1 个人觉得这篇文章赞

摘要 │ 参考文献 (163) │ 国际计量

摘要〈TOP〉

界面析出物为一种成核於沃斯田铁至肥粒铁相变过程当中的细微析出物。自从2004年JFE制钢将界面析出物导入强化肥粒铁的研究以来，至今奈米级阵列型MC碳化物用於肥粒铁单相强化的研究已成果丰硕。本研究目的在於利用此种奈米界面析出物强化传统双相钢之肥粒铁基地，并且透过热处理、显微组织观察，以及机械性质测试得以深入了解界面析出强化双相钢之组织及性质间之关联。
本研究首先单纯探讨界面析出物添加前後双相组织以及机械性质的变化。在精准控制晶粒度以及双相比例之下，吾人发现添加界面析出物後肥粒铁的强化会伴随着麻田散铁的弱化。利用Gleeble热处理所得试片的拉伸结果显示双相钢强度大幅提升，然延性却没有减损，且降伏比提升。後者揭示着相对传统双相钢而言较佳的扩孔性质。透过阶段拉伸并且利用(扫描)穿透式电子显微镜观测变形组织的结果呈现，界面析出物能有效抑制差排的蜂巢状结构的产生，且阻止几何必须差排层的展延，减少变形过程的应变集中。除此之外，试片倾转对於差排以及界面析出物的显像也在本研究被深入探讨：若要观察到界面析出物，析出物所在阵列平面必须要完全与电子束平行；在不同的双束条件之下，差排的柏格斯向量则可以被决定。
针对开发界面析出双相钢当中的合金添加，热膨胀仪结果显现铬及铝虽同为肥粒铁稳定元素，却分别展现为抑制及促进肥粒铁相变态之能力。肥粒铁生成速度影响界面析出物之中的颗粒间距甚钜：铬贡献较慢的肥粒铁生成速度被证实有效减小颗粒间距，增加介面析出物贡献之强度。
在相同的双相比例之下，双相区持温温度的降低使得肥粒铁晶粒度减小、肥粒铁强化并且伴随着麻田散铁的弱化。持温温度较低能造就优异的总体机械性质：较高的强度且优良的延伸率。钼作为硬化能元素，对於抑制肥粒铁成长以及促进析出这两方面皆有显着贡献，在本研究中证实能提升双相钢整体强度。
此外，散乱型析出物以及阵列型界面析出物在本研究中透过选区绕射以及方位关系得以厘清。本研究中观测到的散乱型析出有二：一为於沃斯田铁阶段形成的散乱型高温析出物；另一为双相区肥粒铁生成时伴随而生。前者与肥粒铁基地可能存在有Kurdjumov-Sachs或是Nishiyama-Wessermann之方位关系，亦可能不存在任何方位关系；後者与肥粒铁基地保持有Baker-Nutting (B-N)的方位关系。後者所提及的散乱型析出物文献中均无进行方位关系判定，仅靠形貌叙述。本研究证实这类散乱型析出物其实只是没有平行於入射电子束的阵列型界面析出物，因其与肥粒铁基地均只保有一组B-N方位关系。
利用热膨胀仪实施高温变形对於先前沃斯田铁及随後生成的肥粒铁均有显着影响。变形温度决定沃斯田铁能否发生再结晶行为；变形程度则影响沃斯田铁的细致程度。降低变形温度以及提升变形量均会促进肥粒铁相变以及细化肥粒铁晶粒。沃斯田铁若存在松饼状组织肥粒铁较易不均匀成核，甚至会导致两极化晶粒的产生。界面析出物於高温变形後的所量测到的阵列间距皆有缩小，颗粒间距则无明显改变，两者加乘之下的结果将会增加界面析出物的强化贡献。然而在高温变形过程当中引发的散乱型析出物将会弱化界面析出物的贡献，肥粒铁界面移动快速也将导致界面析出物不易生成。本研究拿两极化晶粒作为深入研究对象进行进一步探讨，并且发现先前生成的细小晶粒内部并无界面析出的发生，导致硬度相较於粗大晶粒为低。此研究成果显示传统细晶强化的概念一旦考虑界面析出物则必须做调整。

并列摘要〈TOP〉

Interphase precipitation forms during austenite-to-ferrite transformation. Since the development of interphase precipitation strengthened ferritic steels by JFE company in 2004, there have been enormous studies regarding the nanometer-sized MC-type carbide strengthened ferrite. The present study makes use of this kind of precipitation to strengthen conventional dual-phase steels. Through heat treatments, microstructural observations, and mechanical property testing, the relationship between microstructures and properties of interphase precipitation strengthened dual-phase steels can be built up.
The present study in the first place simply investigated the addition of interphase precipitation to the dual-phase structures. Under the precise control over structural parameters such as grain size and volume fraction, interphase precipitation was found to strengthen ferrite but weaken martensite. Tensile specimens heat treated by Gleeble showed higher strength with unsacrificed elongation. Yield ratio could also be increased, which implies better hole expansion properties in the present steel. (Scanning) transmission electron microscopy ((S)TEM) was used to ex-situ observe the deformed structures in the dual-phase steel, and we found out that the formation of cell structures and the development of geometrically necessary dislocation (GNDs) can be effectively hindered by interphase precipitation. The strain localization and better stress-strain balance can be achieved by the simple addition of interphase precipitation. Furthermore, effect of the specimen tilting on both interphase precipitation and dislocation imaging was also comprehensively addressed: where for the observation of interphase precipitation, a rigorous edge-on condition is needed (i.e., sheet plane of carbides should be parallel to the incident beam); Burgers vector of dislocations can, on the other hand, be determined by using different two-beam conditions. 
The alloy addition of Cr or Al showed different characteristics of either retarding or accelerating ferrite transformation, which was thoroughly studied by a dilatometer. Different ferrite transformation rates gave rise to different morphologies of interphase precipitation. Addition of Cr was proved to bring about smaller intercarbide spacing than Al, which increased the strength contribution from interphase precipitation.
Under the same volume fraction of martensite, decreasing the dual-phase holding temperatures reduced the ferrite grain size, increasing ferrite hardness, yet weakening martensite hardness. These factors made the overall mechanical properties excellent, which bore higher strength together with good elongation. Mo, as an element to raise hardenability, retarded ferrite transformation and contributes to denser precipitation, which gave rise to increasing the strength of dual-phase structures.
Moreover, the present study clarified the difference between random precipitates and interphase precipitates by using selected area diffraction pattern (SADP) as a tool. Random precipitates can further be divided into two classes: one is random strain-induced precipitation formed in the austenite state; the other is formed in the two-phase holding period. The former holds either Kurdjumov-Sachs, Nishiyama-Wessermann, or none of the above-mentioned orientation relationship with the ferrite matrix, while the latter holds Baker-Nutting orientation relationship instead. The present work initiatively proved that the latter random precipitation holds only single variant Baker-Nutting orientation relationship with the ferrite matrix. Therefore, the seemingly “random” precipitation is regarded as interphase precipitation that is simply not in an edge-on condition by the present author.
Moreover, through dilatometer, hot deformation had great impact on both austenite and the subsequent ferrite transformation. Deformation temperatures determined the ability for recrystallization of austenite; increasing deformation strain, on the other hand, refined austenite structures. It was shown that lower deformation temperature or increased deformation strain lead to faster ferrite transformation and finer ferrite grains. Pancaked austenite structures brought about inhomogeneous nucleation of ferrite grains, even making grain distribution bimodal. Hot deformation decreased the sheet spacings of interphase precipitation, but had nearly no influence on intercarbide spacing, which leads to higher strengthening contribution. However, if high-temperature strain-induced precipitates are also considered, the precipitation hardening will be reduced. High temperature precipitates together with very fast transformation movement are thought to obstruct interphase precipitation from forming. Bimodal grain distribution was taken as a case study in the present research, where earlier-formed tiny-grained ferrite was discovered to be devoid of interphase precipitation but distributed with strain-induced larger precipitation, resulting in a lower hardness than larger-grained counterpart. This result reveals that when interphase precipitation is considered, the concept of strengthening through grain refinement should be modified.

参考文献 ( 163 ) 〈TOP〉

[1] O. Bouaziz, H. Zurob, M.X. Huang, Driving Force and Logic of Development of Advanced High Strength Steels for Automotive Applications, Steel Res. Int. 84(10) (2013) 937-947.
连结：
[4] R.G. Davies, INFLUENCE OF MARTENSITE COMPOSITION AND CONTENT ON PROPERTIES OF DUAL PHASE STEELS, Metallurgical Transactions a-Physical Metallurgy and Materials Science 9(5) (1978) 671-679.
连结：
[5] R.G. Davies, EARLY STAGES OF YIELDING AND STRAIN AGING OF A VANADIUM-CONTAINING DUAL-PHASE STEEL, Metallurgical Transactions a-Physical Metallurgy and Materials Science 10(10) (1979) 1549-1555.
连结：
[6] G.R. Speich, V.A. Demarest, R.L. Miller, FORMATION OF AUSTENITE DURING INTERCRITICAL ANNEALING OF DUAL-PHASE STEELS, Metallurgical Transactions a-Physical Metallurgy and Materials Science 12(8) (1981) 1419-1428.
连结：
[8] A.P. Coldren, G. Tither, DEVELOPMENT OF A MN-SI-CR-MO AS-ROLLED DUAL-PHASE STEEL, Journal of Metals 30(4) (1978) 6-9.
连结：

国际计量

〈TOP〉

E-mail ：

文章公开取用时，将寄通知信至您填写的信箱地址

E-mail ：

使用DOI作为永久连结

引用含有DOI的文献

DOI可强化引用精确性、增强学术圈连结，并给予使用者跨平台的良好使用经验，目前在全世界已有超过五千万个对象申请DOI。 如想对DOI的使用与概念有进一步了解，请参考 （ ） 。

DOI可强化引用精确性、增强学术圈连结，并给予使用者跨平台的良好使用经验，目前在全世界已有超过五千万个对象申请DOI。如想对DOI的使用与概念有进一步了解，请参考（）。