Nano-scaled iron-carbon precipitates in HSLC and HSLA steels  

作　　者：FU Jie WU HuaJie LIU YangChun KANG YongLin 

机构地区：[1]School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China [2]School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China

出　　处：《Science China(Technological Sciences)》2007年第2期166-176,共11页中国科学（技术科学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant No. 50334010);the State Foundation for Key Projects: New Generation of Steels (Grant No. G1998061500)

摘　　要：This paper studies the composition, quantity and particle size distribution of nano-scaled precipitates with size less than 20 nm in high strength low carbon (HSLC) steel and their effects on mechanical properties of HSLC steel by means of mass balance calculation of nano-scaled precipitates measured by chemical phase analysis plus SAXS method, high-resolution TEM analysis and thermodynamics calculation, as well as temper rapid cooling treatment of ZJ330. It is found that there existed a large quantity of nano-scaled iron-carbon precipitates with size less than 18 nm in low carbon steel produced by CSP and they are mainly Fe-O-C and Fe-Ti-O-C precipitates formed below temperature A1. These precipitates have ob- vious precipitation strengthening effect on HSLC steel and this may be regarded as one of the main reasons why HSLC steel has higher strength. There also existed a lot of iron-carbon precipitates with size less than 36 nm in HSLA steels.This paper studies the composition, quantity and particle size distribution of nano-scaled precipitates with size less than 20 nm in high strength low carbon (HSLC) steel and their effects on mechanical properties of HSLC steel by means of mass balance calculation of nano-scaled precipitates measured by chemical phase analysis plus SAXS method, high-resolution TEM analysis and thermodynamics calculation, as well as temper rapid cooling treatment of ZJ330. It is found that there existed a large quantity of nano-scaled iron-carbon precipitates with size less than 18 nm in low carbon steel produced by CSP and they are mainly Fe-O-C and Fe-Ti-O-C precipitates formed below temperature A 1. These precipitates have obvious precipitation strengthening effect on HSLC steel and this may be regarded as one of the main reasons why HSLC steel has higher strength. There also existed a lot of iron-carbon precipitates with size less than 36 nm in HSLA steels.

关 键 词：HSLC STEEL high STRENGTH low alloyed STEEL (HSLA steel) IRON-CARBON PRECIPITATES PRECIPITATION strengthening 

分 类 号：TG142.1[一般工业技术—材料科学与工程]