Influence of isothermal quenching of LAMC CrMnSi cast steel on impact toughness

Abstract

The influence of isothermal quenching process of low-alloy and medium carbon (LAMC) CrMnSi cast steel on the impact toughness was investigated. The microstructure and mechanical property of LAMC CrMnSi cast steel were analyzed by the laser optical modulator, the scanning electron microscopy, the energy dispersive spectrometer, the hardness and impact tests. The experimental results show that the dual phases of bainite and residual austenite can be obtained by the severity isothermal quenching, the fractographies of specimens change from quasicleavage to dimple at 310 °C for 60 min, the impact toughness for specimens at the room temperature isothermally achieves 130 J/cm², meantime and its hardness is more than 45 (HRC).

Keywords

LAMC CrMnSi cast steel / bainite-austenite microstructure / impact toughness / hardness

References

[1] LeeY K, ShinH C. Effect of isothermal transformation temperature on amount of retained austenite and its thermal stability in a bainitic Fe-3% Si-0.45% C-X steel [J]. Scripta Materialia, 2002, 47: 805-809

[2] LiYang-xiang, ChenXiang. Microstructure and mechanical properties of austempered high silion cast steel [J]. Materials Science and Engineering, 2001, 308(A): 277-282

[3] XuPing-guang, BaiBing-zhe, FangHong-sheng. Current status and development of high strength low alloy steel plate[J]. Materials for Mechanical Engineering, 2001, 25(2): 4-8(in Chinese)

[4] HuXiu-lian, GaoYun-xia. Analysis of rupture on high manganese steel lining of ball mill[J]. Metal Heat Treatment, 1999, 5(11): 22-23(in Chinese)

[5] DongYun, JiaYan-qin, XuLi-hong. Analysis of properties and plastical deformation of austenite-bainite steel[J]. Journal of Hebei University of Technology, 2002, 2(1): 67-70

[6] XieJing-pei, LiQing-chun, HeZhen-ming. Wearresistance of casting composite medium manganese austenitic steel[J]. Journal of Luoyang Institute of Technology, 1999, 3(1): 5-9(in Chinese)

[7] ZhouXian-liang. Development and application of new wear resistant bainitic steel[J]. Jiangxi Metallurgical, 1999, 2(1): 13-15(in Chinese)

[8] FangH S, YangJ B. The mechanism of bainite transformation in steels[J]. Scripta Materialia, 2002, 47: 157-162

[9] FangHong-sheng. Microstructure and properties of 1500 Mpa economical bainite/martensite duplex phase steel[J]. Journal of Iron and Steel Research, 2001, 13(3): 31-36(in Chinese)

[10] LiFeng-zhao, AoQing, GuYing. TEM and HREM study on the fine structure and the interfacial structure of bainite[J]. Science in China(Series E), 1996, 39(6): 647-655

[11] FangHong-sheng, WangJia-junBainite Transformation[M], 1999, Beijing, Science Press(in Chinese)

[12] TomitaY, OkawaT. Effect of modified heat treatment on mechanical properties of 300M steel[J]. Mater Sci& Tech, 1995, 11(3): 259-263

[13] PichlerA. TRIP steels with reduced Si content [J]. Steel Research, 1999, 70(1): 459-465 in Chinese)

[14] Teaching-Research Office of Metal and Heat Treatment Analysis of MicrostructureThe Analysis of Microstructure [M], 1980, Harbin, Harbin Institute of Technology Press(in Chinese)

[15] ShuDe-linMechanical Property of Metals [M], 1994, Beijing, Mechanical Industry Press(in Chinese)