摘要
研究了冷轧变形并结合退火处理对共析钢组织球化超细化与性能的影响.结果表明:共析钢经冷轧形变量90%结合600～700℃退火得到了晶粒尺寸为亚微米级铁素体晶粒和颗粒状渗碳体的双相组织.颗粒状渗碳体的尺寸呈双峰分布.与传统球化处理工艺相比,球化时间明显缩短,球化组织细小;其原因是在冷变形过程中产生了高密度位错以及大量空位等缺陷,为碳原子的扩散提供了高速率扩散通道,促进了碳原子的扩散.细小渗碳体粒子在铁素体基体上的弥散分布可以用溶解-再析出机制来解释.冷轧后经700℃退火试样的拉伸塑性略有下降,屈服强度和抗拉强度大幅度提高,但屈强比较高.
The effect of cold roiling followed by annealing on the ultra-refinement of microstructure and the mechanical properties of eutectoid steel was investigated. The experimental results showed that the combination of cold roiling to 90 % and annealing within the temperature range of 600 - 700℃ leads a duplex microstructure consisting of sub-micron ferritic grains and dispersive cementite particles. The distribution of cementite particle size displayed bimodal. In comparison with traditional spheroidizing treatment, the spheroidization time was significantly shortened and the microstructure markedly refined. This could be attributed to the formation of high-density dislocations and vacancies during cold deformation, which provided a high diffusion path of carbon atoms. The formation of dispersive distribution of fine cementite particles could be explained by the mechanism of dissolution-re-precipitation. It is also indicated that the present combined treatment of cold rolling and annealing results in pronounced increases in yield strength and ultimate strength, a slight decrease in tensile plasticity, and a relatively high yield ratio.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2007年第7期689-693,711,共6页
Journal of University of Science and Technology Beijing
基金
国家自然科学基金资助项目(No.50471092)
教育部博士点基金资助项目(No.20050008017)
关键词
共析钢
冷轧
超细晶
球化处理
再结晶退火
eutectoid steel
cold-rolling
ultra-fine grain
spheroidization
recrystallization annealing
