摘要
通过热轧试验和组织观察,研究了热轧变形温度、单道次压下率等对EB炉铸态板坯在热轧过程中的组织演变和再结晶的影响规律。发现经过热轧前的板坯加热,EB炉铸坯比VAR锻坯的晶粒尺寸大几百倍,粗大的EB炉铸坯晶粒组织不利于热轧过程中发生再结晶。通过提高热轧温度(≥850℃)、减小单道次压下量、降低热轧变形速度,可以促使热轧组织充分再结晶;探讨采用薄坯高温开轧、高温终轧、高温卷取,争取热轧卷获得较大比例的再结晶组织,从而可以省略传统的热轧板退火再结晶工艺。发现当热轧温度为850℃时,存在一个细化再结晶晶粒的临界压下率(43.6%),当热轧压下率低于43.6%时,提高热轧压下率可显著细化热轧卷中再结晶晶粒,超过临界压下率,热轧卷中再结晶晶粒尺寸几乎保持不变。当热轧温度≤810℃,存在一个临界压下率开动再结晶形核过程,随着热轧温度降低,临界压下率逐渐增大。
The influences of hot rolling deformation temperature and single pass reduction rate on the microstructure evolution and recrystallization of EB furnace slab during hot rolling were studied by hot rolling experiments and microstructure observation.It is found that the grain size of EB furnace slab is hundreds of times larger than that of VAR forging slab after heating the slab before hot rolling,and the coarse grain structure of EB furnace slab is not conducive to recrystallization during hot rolling.By increasing the rolling temperature(≥ 850 ℃),reducing the single pass reduction and decreasing the hot rolling deformation speed,the hot rolling structure can be fully recrystallized.The high-temperature start rolling,high-temperature finishing rolling and high-temperature coiling of thin slab were discussed to obtain a large proportion of recrystallization structure of the hot rolling coil,so that the traditional annealing recrystallization process of hot rolling plate can be omitted.It is found that when the hot rolling temperature is 850 ℃,there is a critical reduction rate(43.6%) for refining recrystallized grains.When the reduction rate is lower than 43.6%,increasing the reduction rate can significantly refine recrystallized grains in the hot rolling coil,which exceeds the critical reduction rate,and the recrystallized grain size in the hot rolling coil almost remains unchanged.When the hot rolling temperature is lower than 810 ℃,there is a critical reduction rate to start recrystallization nucleation.With the decrease of the hot rolling temperature,the critical reduction rate increases gradually.
作者
崔岩
孙新军
张志波
雍岐龙
Cui Yan;Sun Xinjun;Zhang Zhibo;Yong Qilong(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,Hebei,China;Institute of Structural Steels,Central Iron and Steel Research Institute,Beijing 100081,China;Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China)
出处
《钢铁钒钛》
CAS
北大核心
2020年第3期53-58,共6页
Iron Steel Vanadium Titanium
基金
国家重点研发计划项目(2016YFB0301200)
河北省自然科学基金项目(E2016209390)。
关键词
TA1
板坯
EB炉
热轧
再结晶
TA1
slab
EB furnace
hot rolling
recrystallization
作者简介
崔岩(1979—),男,博士,副教授,主要研究方向为钛及钛合金、金属基复合材料、钢铁材料,E-mail:jack-cui5090@163.com。
