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 ...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.展开更多
On the basis of the effect of carbon precipitation on the microstructure and properties of steel products below At temperature, a new thermal treatment method （temper-rapid cooling process） was studied. By the tempe...On the basis of the effect of carbon precipitation on the microstructure and properties of steel products below At temperature, a new thermal treatment method （temper-rapid cooling process） was studied. By the temper-rapid cooling process, the yield strengths of the high strength low carbon （HSLC） steel ZJ330 and SPA-H produced using the compact strip production （CSP） process increased from 340 to about 410 MPa and from 410 to about 450 MPa, respectively. The results indirectly indicated that there existed nanoscaled iron-carbon precipitates that have obvious precipitation effect on low carbon steel produced by CSP. The prospect of application is discussed.展开更多
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)
文摘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.
基金the National Natural Science Foundation of China (No.50334010).
文摘On the basis of the effect of carbon precipitation on the microstructure and properties of steel products below At temperature, a new thermal treatment method （temper-rapid cooling process） was studied. By the temper-rapid cooling process, the yield strengths of the high strength low carbon （HSLC） steel ZJ330 and SPA-H produced using the compact strip production （CSP） process increased from 340 to about 410 MPa and from 410 to about 450 MPa, respectively. The results indirectly indicated that there existed nanoscaled iron-carbon precipitates that have obvious precipitation effect on low carbon steel produced by CSP. The prospect of application is discussed.
