Ⅰ. THE VALENCE ELECTRON STRUCTURES OF MARTENSITE IN LOW ALLOY ULTRAHIGH-STRENGTH STEELS AND THE SEGREGATION OF C-ME IN MARTENSITEThe valence electron structures ofmartensite in 30CrMnSiNi<sub>2</sub>A and...Ⅰ. THE VALENCE ELECTRON STRUCTURES OF MARTENSITE IN LOW ALLOY ULTRAHIGH-STRENGTH STEELS AND THE SEGREGATION OF C-ME IN MARTENSITEThe valence electron structures ofmartensite in 30CrMnSiNi<sub>2</sub>A and Gc-4 steels can be established based on Refs. [1—3]. To be brief, only σ, n<sub>A</sub> and n<sub>c</sub><sup>D</sup> are listed in Table 1, which are the values of electron structures of martensite in 30CrMnSi<sub>2</sub>A and Gc-4 steels.展开更多
An 1100 MPa grade ultra-high strength steel with different martensite fine structures, characterized by prior austenite grain size, martensite packet size, block width and lath width, was studied by various heat treat...An 1100 MPa grade ultra-high strength steel with different martensite fine structures, characterized by prior austenite grain size, martensite packet size, block width and lath width, was studied by various heat treatment processes. The result shows that with decreasing prior austenite grain size, both the packet size and block width decrease, while the lath width has virtually no change. Accordingly, both strength and toughness increase, while total elongation decreases. The yield strength has a Hall Petch type relationship with the prior austenite grain size, packet size and block width, and the block width may be regarded as a key factor influencing strength. On the other hand, the ductile to brittle transition temperature （DBTT） is found to be more related lo the packet size, which may be considered as a dominant factor influencing toughness.展开更多
文摘Ⅰ. THE VALENCE ELECTRON STRUCTURES OF MARTENSITE IN LOW ALLOY ULTRAHIGH-STRENGTH STEELS AND THE SEGREGATION OF C-ME IN MARTENSITEThe valence electron structures ofmartensite in 30CrMnSiNi<sub>2</sub>A and Gc-4 steels can be established based on Refs. [1—3]. To be brief, only σ, n<sub>A</sub> and n<sub>c</sub><sup>D</sup> are listed in Table 1, which are the values of electron structures of martensite in 30CrMnSi<sub>2</sub>A and Gc-4 steels.
文摘An 1100 MPa grade ultra-high strength steel with different martensite fine structures, characterized by prior austenite grain size, martensite packet size, block width and lath width, was studied by various heat treatment processes. The result shows that with decreasing prior austenite grain size, both the packet size and block width decrease, while the lath width has virtually no change. Accordingly, both strength and toughness increase, while total elongation decreases. The yield strength has a Hall Petch type relationship with the prior austenite grain size, packet size and block width, and the block width may be regarded as a key factor influencing strength. On the other hand, the ductile to brittle transition temperature （DBTT） is found to be more related lo the packet size, which may be considered as a dominant factor influencing toughness.
