In recent years,despite the global economic recession and steel oversupply,the demand for high strength steel( HSS) and advanced high strength steel( AHSS) sheets has robustly increased. To supply the materials needed...In recent years,despite the global economic recession and steel oversupply,the demand for high strength steel( HSS) and advanced high strength steel( AHSS) sheets has robustly increased. To supply the materials needed for automotive manufacturing,various AHSS products and application technologies have been developed by Baosteel,including the 1st,2nd,and 3rd Gen. AHSS,which makes Baosteel the world’s first steel maker to commercially provide all three generations of AHSS. Recently,the new Gen.( the 2nd and 3rd Gen. combined)AHSS products,which feature ultra-high strength and enhanced ductility,have drawn great attention from both steel makers and the automotive industry as these products can be used to produce auto parts with complicated shapes by cold forming and have great potential for manufacturing car bodies that are lighter in weight and have higher crash resistance. In this article,the concepts,properties,and applications of Baosteel’s new Gen. AHSS products,including quenching and partitioning( QP) steels,twinning-induced-plasticity( TWIP) steels,and Medium-Mn( Mn-TRIP)steels,are described and reviewed. Moreover,the progress of the Baosteel light-weight steel car body( BCB) was reported.展开更多
800 MPa grade new ultra-low carbon bainitic （NULCB） steel is the recently developed new generation steel. The microstructure in the coarse-grained heat affected zone （CGHAZ） of NULCB steel under laser welding cond...800 MPa grade new ultra-low carbon bainitic （NULCB） steel is the recently developed new generation steel. The microstructure in the coarse-grained heat affected zone （CGHAZ） of NULCB steel under laser welding conditions was investigated by thermal simulation. The influence of the cooling time from 800℃ to 500℃.t8/5 （0.3-30 s）, on the microstructure of the CGHAZ was discussed. The experimental results indicate that the microstructnre of the CGHAZ is only the granular bainite which consists of bainitic ferrite （BF） lath and M-A constituent while t8/5 is 0.3-30 s. The M-A constituent consists of twinned martensite and residual austenite, and the change of the volume fraction of the residual austenite in the M-A constituent is very small when t8/5 is between 0.3 and 30 s. The morphology of the M-A constituent obviously changes with the variation of t8/5.As t8/5 increases, tile average width, gross and shape parameter of the M-A constituent increase, while the line density of the M-A constituent decreases.展开更多
The fact-developing iron and steel industry provides the base for China economy to grow continually, stably and healthily for many years. This paper analyzes the situation and the disparity, which the iron and steel i...The fact-developing iron and steel industry provides the base for China economy to grow continually, stably and healthily for many years. This paper analyzes the situation and the disparity, which the iron and steel industry faces, and attests that the new industrialization path is the strategic choice for the Chinese iron and steel industry to develop continuously, and carries on the thorough discussion to the connotation of this choice.展开更多
Since China began to pursue the policies of reform and opening, its iron and steel industry has been following the strategic principle of making use of "two resources, two markets and two kinds of funds," an...Since China began to pursue the policies of reform and opening, its iron and steel industry has been following the strategic principle of making use of "two resources, two markets and two kinds of funds," and has made eyecatching progress in expanding opening to the outside world and international cooperation. In 1993, the industry utilized some US$900 million in foreign capital,展开更多
A new combined steel lead damper (NCSLD) was presented. Construction and working mechanism of NCSLD were introduced,pseudo-static tests of the small size dampers which would be used in the subsequent shaking table tes...A new combined steel lead damper (NCSLD) was presented. Construction and working mechanism of NCSLD were introduced,pseudo-static tests of the small size dampers which would be used in the subsequent shaking table tests were carried out for the study of mechanical properties of NCSLD using electro-hydraulic servo press-shear machine. Processing technology of the damper was improved. Shaking table tests under two-dimensional excitation on structural aseismic control of a one-story structure model were carried out using the small size NCSLD; parameters of the structure and shaking table were also introduced. Results indicate that process improvement is beneficial to the implementation of working mechanism of the damper,NCSLD has full hysteresis loop which takes on bilinearity,NCSLD has obvious energy dissipation effect and it can control structural seismic response effectively.展开更多
文摘In recent years,despite the global economic recession and steel oversupply,the demand for high strength steel( HSS) and advanced high strength steel( AHSS) sheets has robustly increased. To supply the materials needed for automotive manufacturing,various AHSS products and application technologies have been developed by Baosteel,including the 1st,2nd,and 3rd Gen. AHSS,which makes Baosteel the world’s first steel maker to commercially provide all three generations of AHSS. Recently,the new Gen.( the 2nd and 3rd Gen. combined)AHSS products,which feature ultra-high strength and enhanced ductility,have drawn great attention from both steel makers and the automotive industry as these products can be used to produce auto parts with complicated shapes by cold forming and have great potential for manufacturing car bodies that are lighter in weight and have higher crash resistance. In this article,the concepts,properties,and applications of Baosteel’s new Gen. AHSS products,including quenching and partitioning( QP) steels,twinning-induced-plasticity( TWIP) steels,and Medium-Mn( Mn-TRIP)steels,are described and reviewed. Moreover,the progress of the Baosteel light-weight steel car body( BCB) was reported.
文摘800 MPa grade new ultra-low carbon bainitic （NULCB） steel is the recently developed new generation steel. The microstructure in the coarse-grained heat affected zone （CGHAZ） of NULCB steel under laser welding conditions was investigated by thermal simulation. The influence of the cooling time from 800℃ to 500℃.t8/5 （0.3-30 s）, on the microstructure of the CGHAZ was discussed. The experimental results indicate that the microstructnre of the CGHAZ is only the granular bainite which consists of bainitic ferrite （BF） lath and M-A constituent while t8/5 is 0.3-30 s. The M-A constituent consists of twinned martensite and residual austenite, and the change of the volume fraction of the residual austenite in the M-A constituent is very small when t8/5 is between 0.3 and 30 s. The morphology of the M-A constituent obviously changes with the variation of t8/5.As t8/5 increases, tile average width, gross and shape parameter of the M-A constituent increase, while the line density of the M-A constituent decreases.
文摘The fact-developing iron and steel industry provides the base for China economy to grow continually, stably and healthily for many years. This paper analyzes the situation and the disparity, which the iron and steel industry faces, and attests that the new industrialization path is the strategic choice for the Chinese iron and steel industry to develop continuously, and carries on the thorough discussion to the connotation of this choice.
文摘Since China began to pursue the policies of reform and opening, its iron and steel industry has been following the strategic principle of making use of "two resources, two markets and two kinds of funds," and has made eyecatching progress in expanding opening to the outside world and international cooperation. In 1993, the industry utilized some US$900 million in foreign capital,
基金Sponsored by the National Natural Science Foundation of China (Grant No. 50508012)Science &Technology Plan Project of Guangdong Province(Grant No. 20055190030)+1 种基金Key Basic Research Project of Science and Technology Ministry (Grant No. 2004CCA03300)Science &Technology Project of Guangzhou Education Bureau(Grant No.08C05)
文摘A new combined steel lead damper (NCSLD) was presented. Construction and working mechanism of NCSLD were introduced,pseudo-static tests of the small size dampers which would be used in the subsequent shaking table tests were carried out for the study of mechanical properties of NCSLD using electro-hydraulic servo press-shear machine. Processing technology of the damper was improved. Shaking table tests under two-dimensional excitation on structural aseismic control of a one-story structure model were carried out using the small size NCSLD; parameters of the structure and shaking table were also introduced. Results indicate that process improvement is beneficial to the implementation of working mechanism of the damper,NCSLD has full hysteresis loop which takes on bilinearity,NCSLD has obvious energy dissipation effect and it can control structural seismic response effectively.
