电脉冲辅助轧制SUS304极薄带的微观组织及力学性能
Microstructure and mechanical properties of SUS304 ultra-thin strip rolled with electric pulse assistance
范婉婉 1任忠凯 1刘晓 1魏书凤 1刘奇 1王涛1
作者信息
- 1. 太原理工大学机械与运载工程学院, 山西 太原 030024;太原理工大学先进金属复合材料成形技术与装备教育部工程研究中心, 山西 太原 030024;太原理工大学金属成形技术与重型装备全国重点实验室, 山西 太原 030024
- 折叠
摘要
SUS304不锈钢极薄带是众多高精尖领域的重要原材料,但其变形抗力大导致极薄带的轧制生产工艺复杂.将脉冲电流加载至SUS304不锈钢极薄带的轧制变形中,研究脉冲电流辅助对极薄带轧制变形的影响.通过室温轧制和不同脉冲频率下的电脉冲辅助轧制试验,使用EBSD和XRD对轧后试样进行微观表征,研究了电脉冲辅助轧制对极薄带组织形貌、晶粒取向以及物相演变的影响.结合力学性能测试,分析了脉冲电流对轧制试样力学性能的影响.结果表明,电脉冲辅助轧制促使试样发生动态回复,增大电脉冲频率可加速其动态过程,600 Hz通电试样以亚结构晶粒为主(98.3%).加载脉冲电流可改变极薄带的轧制变形机制,使其从相变马氏体转变为形变诱发孪晶.脉冲电流产生的热效应和非热效应皆可促进位错脱钉,使得相同变形量下电脉冲辅助轧制试样的位错密度明显低于室温轧制试样,加工硬化减弱、力学性能改善.同时,电脉冲辅助轧制有助于弱化轧制变形织构、增加织构类型,可改善变形试样的各向异性,有利于提高试样的塑性变形能力.对比室温轧制试样,600 Hz通电试样的显微硬度下降了 33.4%,屈服强度降低了 15.2%,断裂伸长率提高了 249.6%,塑性变形能力恢复至原材料的30%.由此可见,电脉冲辅助SUS304不锈钢极薄带轧制变形,可减少加工硬化、降低变形抗力、提高塑性变形能力,有望突破最小可轧厚度,拓宽其应用领域.
Abstract
SUS304 stainless steel ultra-thin strip is an important raw material for many high-precision fields,and its large deformation resistance leads to complex rolling production processes for ultra-thin strips.Pulse current was loaded into the rolling deformation of SUS304 ultra-thin strip to study the effect of pulse current assistance on the rolling deformation of ultra-thin strip.Through room temperature rolling and electric assisted rolling experiments at different pulse frequencies,EBSD and XRD were used to characterize the microstructure of the rolled samples,and the effects of electric pulse assisted rolling on the microstructure morphology,grain orientation,and phase evolution of ultra-thin strips were studied.Combined with mechanical property tests,the effect of pulse current on the mechani-cal properties of rolled specimens was analyzed.The results indicate that electric pulse assisted rolling promotes dynamic recovery of the sample,and increasing the frequency of the electric pulse can accelerate its dynamic process,with sub-structural grains predominating in the 600 Hz energized rolled samples(98.3%).Loading pulse current can change the rolling deformation mechanism of ultra-thin strip from phase transformation martensite to deformation-induced twinning.The thermal and non-thermal effects generated by pulse current can promote disloca-tion detachment,resulting in a significantly lower dislocation density in electrically rolled samples under the same deformation compared to the room temperature rolled sample,weakened work hardening,and improved mechanical properties.At the same time,electric pulse assisted rolling helps to weaken the rolling deformation texture and increase the type of texture,which can improve the anisotropy of the deformed sample,and is conducive to improving the plastic deformation ability of the sample.Compared with the room temperature rolling sample,the microhardness of the 600 Hz electrified rolling sample decreased by 33.4%,the yield strength decreased by 15.2%,the fracture elongation increased by 249.6%,and the plastic deformation ability restored to 30%of the raw material.It can be seen that pulse current assisted SUS304 ultra-thin strip rolling deformation can reduce work hardening,reduce defor-mation resistance,and improve plastic deformation ability.It is expected to break through the minimum rollable thickness and expand its application fields.
关键词
SUS304极薄带/电脉冲辅助轧制/加工硬化/位错密度/变形机制Key words
SUS304 ultra-thin strip/electric pulse assisted rolling/work hardening/dislocation density/deforma-tion mechanism引用本文复制引用
基金项目
国家自然科学基金(51974196)
国家自然科学基金区域联合重点项目(U22A20188)
中央引导地方科技发展资金项目(YDZX20191400002149)
山西省基础研究计划自由探索类自然科学研究青年项目(20210302124426)
出版年
2024
NETL
NSTL
万方数据