Non-quenched and tempered(NQT)steels have been applied for auto forging products at the aim of lower cost since 1980’s in China.Without quenching and tempering processes,the cost of heat treatment was greatly decreas...Non-quenched and tempered(NQT)steels have been applied for auto forging products at the aim of lower cost since 1980’s in China.Without quenching and tempering processes,the cost of heat treatment was greatly decreased,so they are widely applied in car forgings such as crankshaft,connecting rod.Recently,with the aim of improving performance and reducing production cost,new technologies,such as:reductions of microalloyed elements,microstructure refining,and mechanical properties forecast have been developed in China auto industry.The designation,processing,properties prediction and microstructure of auto components have been controlled comprehensively.With the development of new technologies,NQT steel gradually began to be applied to product important parts,and replace Quenching and Tempering(QT)steels.Both steel makers and end product users are expressed their desire to share benefits of technological innovation.The technologies will have a huge developing space and very bright developing prospects in motor parts industry in future.展开更多
The Qinling Orogenic Belt(QOB)is a composite continental orogenic belt that has experienced many tectonic events.The QOB is subdivided into the following three litho-tectonic units:the North Qinling terrane,the Middle...The Qinling Orogenic Belt(QOB)is a composite continental orogenic belt that has experienced many tectonic events.The QOB is subdivided into the following three litho-tectonic units:the North Qinling terrane,the Middle Qinling microplate and the South Qinling terrane.The North Qinling Terrane(NQT)underwent destruction and lithospheric thinning during the late Mesozoic,accompanied by extensive magmatic activity and increased surface heat flux,led to large-scale tectonic extension(e.g.,Ren Shenglian et al.,2016).The Shirenshan gneiss is located along the contact between the NQT and the North China Block(Fig.1).Previous studies suggested that it was produced as a result of the northward subduction of the NQT beneath the North China Block(e.g.,Wang Jingya et al.,2017).Therefore,it is significant to study its structural geology,petrology,geochemistry and chronology in order to understand the tectonic settings and the interaction between the Middle Qinling microplate and the North China Block.展开更多
文摘Non-quenched and tempered(NQT)steels have been applied for auto forging products at the aim of lower cost since 1980’s in China.Without quenching and tempering processes,the cost of heat treatment was greatly decreased,so they are widely applied in car forgings such as crankshaft,connecting rod.Recently,with the aim of improving performance and reducing production cost,new technologies,such as:reductions of microalloyed elements,microstructure refining,and mechanical properties forecast have been developed in China auto industry.The designation,processing,properties prediction and microstructure of auto components have been controlled comprehensively.With the development of new technologies,NQT steel gradually began to be applied to product important parts,and replace Quenching and Tempering(QT)steels.Both steel makers and end product users are expressed their desire to share benefits of technological innovation.The technologies will have a huge developing space and very bright developing prospects in motor parts industry in future.
基金supported by the National Science Foundation of China(grants No.41272213,41572177,41573023,41502193 and 41272222)
文摘The Qinling Orogenic Belt(QOB)is a composite continental orogenic belt that has experienced many tectonic events.The QOB is subdivided into the following three litho-tectonic units:the North Qinling terrane,the Middle Qinling microplate and the South Qinling terrane.The North Qinling Terrane(NQT)underwent destruction and lithospheric thinning during the late Mesozoic,accompanied by extensive magmatic activity and increased surface heat flux,led to large-scale tectonic extension(e.g.,Ren Shenglian et al.,2016).The Shirenshan gneiss is located along the contact between the NQT and the North China Block(Fig.1).Previous studies suggested that it was produced as a result of the northward subduction of the NQT beneath the North China Block(e.g.,Wang Jingya et al.,2017).Therefore,it is significant to study its structural geology,petrology,geochemistry and chronology in order to understand the tectonic settings and the interaction between the Middle Qinling microplate and the North China Block.