预变形量对大晶粒低碳钢烘烤硬化性能影响的内耗研究  

Internal friction on effect of pre-deformation on bake hardening in large crystalline size low carbon steel

作　　者：张恒毅[1,2] 李维娟[2] 金晓龙 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110004 [2]辽宁科技大学材料与冶金学院,辽宁鞍山114051 [3]鞍钢集团钢铁研究院,辽宁鞍山114009

出　　处：《金属热处理》2015年第10期99-104,共6页Heat Treatment of Metals

基　　金：国家自然科学基金(51274121)

摘　　要：测试了大晶粒尺寸低碳钢不同预变形后的烘烤硬化性能及其变形态和烘烤态的内耗曲线,采用透射电镜观察试样位错的形态。结果表明,不同预变形的大晶粒低碳钢的烘烤硬化值（BH2）均为负值;预变形量在2%~10%范围内,随着预变形量的增大,BH2先增大后减小,在预变形量为5%时,BH2最大,SKK峰高最大;烘烤态的SKK峰的峰高变化趋势和位错密度都与BH2变化趋势相同;变形态Snoek峰的峰高逐渐减小,SKK峰的峰高逐渐增加。与变形态相比较,预变形2%的烘烤态Snoek峰的峰高增加,5%和10%的Snoek峰的峰高减小;预变形2%、5%和10%的烘烤态SKK峰高增加。烘烤硬化机制与Cottrell气团密度相关。Bake hardening property and internal friction curves in pre-deformed and baked state for different pre-deformations of coarse grained low carbon steel were measured. TEM was used to characterize the dislocation distribution in bake hardening treated samples. The results show that the bake hardening properties（ BH2values） are negative,which are increased by increasing the pre-deformation from 2% to5% and then are decreased by increasing the pre-deformation from 5% to 10%. The BH2 value of the sample with pre-deformation 5%reaches the maximum value and the height of SKK internal friction peak is observed to be the maximum also. With increasing predeformation,both of BH2 value and SKK peak height are similarly varied. Peak height of Snoek peak in pre-deformed state decreases gradually and that of SKK peak increases. Compared with the pre-deformed state,peak height of Snoek peak in baked state with predeformation 2% increases and those with pre-deformation 5% and 10% decrease. Peak height of SKK peak in baked state with predeformation 2%,5% and 10% increase. Bake hardening mechanism is associated with Cottrell atmosphere mass density.

关 键 词：低碳钢 预变形 位错密度 BH2 Snoek峰 SKK峰 

分 类 号：TG142.13[一般工业技术—材料科学与工程]