Cyclic loading behavior and microstructure characterization of ultra-high strength steel Q&P980

HAN Fei; ZHOU ZiHao; WANG Yun

doi:10.16511/j.cnki.qhdxxb.2018.26.030

PDF(4173 KB)

Journal of Tsinghua University(Science and Technology) ›› 2018, Vol. 58 ›› Issue (7) : 677-683. DOI: 10.16511/j.cnki.qhdxxb.2018.26.030

MECHANICAL ENGINEERING

Cyclic loading behavior and microstructure characterization of ultra-high strength steel Q&P980

{{article.zuoZhe_EN}}

Author information +

History +

Abstract

The true stress-strain curve for ultra-high strength steel Q&P980 is obtained through cyclic loading of the ultra-high strength steel in terms of the number of cycles, cyclic position and anisotropy of the cyclic tensile test. The properties of the unloading ring were also analyzed to accurately characterize the mechanical properties. A metallographic microscope using X-ray diffraction (XRD) was then used to study the microstructural changes. The results show that increasing the deformation reduced the slope of the unloading and reloading curves. In addition, reducing the austenite content increased the springback strain, elongation and strength, which is called the transformation induced plasticity (TRIP) effect. For similar amounts of deformation, increasing the number of cycles did not increase the springback strain but reduce it when the cycle number increased to 10. The cyclic loading weakens the sheet anisotropy, but has little effect on the elastic modulus and springback.

Key words

ultra-high strength steel / repeated tensile unloading / tensile tests / microstructure

Cite this article

EndNote

Ris (Procite)

Bibtex

Download Citations

HAN Fei, ZHOU ZiHao, WANG Yun. Cyclic loading behavior and microstructure characterization of ultra-high strength steel Q&P980[J]. Journal of Tsinghua University(Science and Technology). 2018, 58(7): 677-683 https://doi.org/10.16511/j.cnki.qhdxxb.2018.26.030

References

[1] 朱国明, 康永林, 朱帅. 汽车用超高强Q&P钢的工艺与组织性能研究[J]. 机械工程学报, 2017, 53(12):110-117.ZHU G M, KANG Y L, ZHU S. Study on process, microstructure and property of ultra-high strength Q&P steel for automobile[J]. Journal of Mechanical Engineering, 2017, 53(12):110-117. (in Chinese)
[2] 江海涛, 唐荻, 米振莉, 等. 配分工艺对低碳Q&P钢中残余奥氏体的影响[J]. 材料科学与工艺, 2011, 19(1):99-103.JIANG H T, TANG D, MI Z L, et al. Effect of partitioning parameters on the retained austenite in low-carbon Q&P Steel[J]. Materials Science and Technology, 2011, 19(1):99-103. (in Chinese)
[3] 蒯振, 陈银莉, 赵爱民, 等. 低碳Si-Mn系Q&P钢不同配分时间的热处理工艺[J]. 金属热处理, 2012, 37(11):95-99.KUAI Z, CHEN Y L, ZHAO A M, et al. Heat treatment process of low carbon Si-Mn Q&P steel with different partitioning time[J]. Heat Treatment of Metals, 2012, 37(11):95-99. (in Chinese)
[4] 孙珊珊. 卸载循环对Q&P980钢微观组织影响的研究[D]. 长春:吉林大学, 2016.SUN S S, Study on the effect of unloading cycle on microstructure of Q&P980 steel[D]. Changchun:Jilin University, 2016. (in Chinese)
[5] 丁磊, 林建平, 庞政, 等. 考虑TRIP效应的Q&P980超高强度钢多相本构模型[J]. 塑性工程学报, 2013, 20(4):23-26.DING L, LIN J P, PANG Z, et al. Multiphase constitutive model of ultra-high strength steel Q&P980 coupling with TRIP effect[J]. Journal of Plasticity Engineering, 2013, 20(4):23-26. (in Chinese)
[6] 何忠平, 何燕霖, 高毅, 等. 低硅无铝中碳TRIP钢中残留奥氏体的机械稳定性[J]. 材料热处理学报, 2011, 32(s1):44-47, 51.HE Z P, HE Y L, GAO Y, et al. Mechanical stability of retained austenite in low-silicon, non-aluminum and medium-carbon TRIP steels[J]. Transactions of Materials and Heat Treatment, 2011, 32(s1):44-47, 51. (in Chinese)
[7] 余海燕, 陈关龙, 李淑慧, 等. 不同应变方式下TRIP钢中残余奥氏体的体积分数随应变量的变化[J]. 钢铁研究学报, 2005, 17(2):48-51, 78.YU H Y, CHEN G L, LI S H, et al. Change of volume fraction of austenite with strain in TRIP steel[J]. Journal of Iron and Steel Research, 2005, 17(2):48-51, 78. (in Chinese)
[8] 于婷. 汽车用高强塑第三代薄板钢非弹性回复行为的研究[D]. 长春:吉林大学, 2015.YU T. Research on inelastic recovery behavior of the third generation automobile sheet steels presenting with ultrahigh strength and high ductility[D]. Changchun:Jilin University, 2015. (in Chinese)
[9] KIM H, KIM C, BARLAT F, et al. Nonlinear elastic behaviors of low and high strength steels in unloading and reloading[J]. Materials Science and Engineering:A, 2013, 562:161-171.
[10] PAVLINA E J, LIN C J, MENDIGUREN J, et al. Effects of microstructure on the variation of the unloading behavior of DP780 steels[J]. Journal of Materials Engineering and Performance, 2015, 24(10):3737-3745.
[11] LEE J Y, LEE M G, BARLAT F, et al. Piecewise linear approximation of nonlinear unloading-reloading behaviors using a multi-surface approach[J]. International Journal of Plasticity, 2017, 93:112-136.
[12] YOSHIDA F, UEMORI T. A model of large-strain cyclic plasticity describing the Bauschinger effect and workhardening stagnation[J]. International Journal of Plasticity, 2002, 18(5-6):661-686.
[13] ANDAR M O, KUWABARA T, YONEMURA S, et al. Elastic-plastic and inelastic characteristics of high strength steel sheets under biaxial loading and unloading[J]. ISIJ International, 2010, 50(4):613-619.
[14] 徐虹, 刘亚楠, 于婷, 等. 双相钢DP780在循环加载-卸载过程中的非弹性回复行为及其微观机理[J]. 吉林大学学报:工学版, 2017, 47(1):191-198. XU H, LIU Y N, YU T, et al. Inelastic recovery behavior and microscopic mechanism of high strength DP780 steel during cyclic loading-unloading[J]. Journal of Jilin University (Engineering and Technology Edition), 2017, 47(1):191-198. (in Chinese)