Martensitic microstructure in quenched and tempered 17CrlMiMo6 steel with the prior austenite grain size ranging from 6 μm to 199 μm has been characterized by optical metallography (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The yield strength and the toughness of the steel with various prior austenite grain sizes were tested and correlated with microstructure characteristics. Results show that both the prior austenite grain size and the martensitic packet size in the 17CrNiMo6 steel follow a Hall-Petch relation with the yield strength. When the prior austenite grain size was refined from 199 μm to 6 μm , the yield strength increased by 235 MPa, while the Charpy U-notch impact energy at 77 K improved more than 8 times, indicating that microstructure refinement is more effective in improving the resistance to cleavage fracture than in increasing the strength. The fracture surfaces implied that the unit crack path for cleavage fracture is identified as being the packet.
参考文献
| [1] | T Maki;K Tsuzaki;I Tamura .[J].Transactions of the Iron and Steel Institute of Japan,1980,20(04):207. |
| [2] | S. Morito;H. Tanaka;R. Konishi .The morphology and crystallography of lath martensite in Fe-C alloys[J].Acta materialia,2003(6):1789-1799. |
| [3] | G Krauss .[J].Materials Science and Engineering A:Structural Materials Properties Microstructure and Processing,1999,273-275:40. |
| [4] | G Krauss .[J].ISIJ International,1995,35(04):349. |
| [5] | L. Ryde .Application of EBSD to analysis of microstructures in commercial steels[J].Materials Science and Technology: MST: A publication of the Institute of Metals,2006(11):1297-1306. |
| [6] | C K Yao;Z Xu .[J].Materials Chemistry and Physics,1986,14(06):559. |
| [7] | M J Roberts .[J].Metallurgical and Materials Transactions,1970,1(12):3287. |
| [8] | A. Di Schino;J.M. Kenny .Grain refinement strengthening of a micro-crystalline high nitrogen austenitic stainless steel[J].Materials Letters,2003(12):1830-1834. |
| [9] | M.Y. Liu;B. Shi;C. Wang .Normal Hall-Petch behavior of mild steel with submicron grains[J].Materials Letters,2003(19):2798-2802. |
| [10] | R Ishibashi;H Arakawa;T Abe;Y.Aono .[J].ISIJ International,2000,40(zk):169. |
| [11] | C C Anya;T N Baker .[J].Material Science and Engineering,1989,A118:197. |
| [12] | H J Rack .[J].Material Science and Engineering,1978,34(03):263. |
| [13] | T Swarr;G Krauss .[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1976,7A(01):41. |
| [14] | L A Norstrom .[J].Scandinavian Journal of Metallurgy,1976,5(04):159. |
| [15] | Y Tomita;K Okabayashi .[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1986,17A(07):1203. |
| [16] | T Inoue;S Matsuda;Y Okamura;K.Aoki .[J].Transactions of the Japan Institute of Metals,1970,11(01):36. |
| [17] | J P Naylor .[J].Metallurgical and Materials Transactions A:Physical Metallurgy and Materials Science,1979,10A(07):861. |
| [18] | V. Randle;P. Davies .Crystallography of brittle fracture and deformation twinning in ferritic steels[J].Materials Science and Technology: MST: A publication of the Institute of Metals,2005(11):1275-1281. |
| [19] | R. Ayer;R. R. Mueller;T. Neeraj .Electron backscattered diffraction study of cleavage fracture in pure iron[J].Materials Science & Engineering, A. Structural Materials: Properties, Misrostructure and Processing,2006(1/2):243-248. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%