Guan Hailong,Yue Jianbo,Tian Jialong,et al.Effect of Nickel on Continuous Cooling Transition Law and Impact Energy of New Hot Work Die Steel[J].Special Steel,2024,45(06):108-116.
Guan Hailong,Yue Jianbo,Tian Jialong,et al.Effect of Nickel on Continuous Cooling Transition Law and Impact Energy of New Hot Work Die Steel[J].Special Steel,2024,45(06):108-116. DOI: 10.20057/j.1003-8620.2024-00087.
Effect of Nickel on Continuous Cooling Transition Law and Impact Energy of New Hot Work Die Steel
The continuous cooling transition curve (CCT curve) and impact energy curve of QDH of the new hot work die steel with 0.8% Ni and without Ni were determined by thermal expansion phase change instrument and impact testing machine, and the influence of Ni on the continuous transformation law and impact energy of QDH steel were analyzed by combining the microstructure and hardness. The test results of the
rmal expansion curve show that Ni element can significantly reduce the critical phase transition point (A
c1
, A
c3
and M
s
) of QDH steel, expand the austenite phase region, shift the CCT curve to the right as a whole, reduce the critical cooling rate of pearlite from 0.03 ℃/s to less than 0.02 ℃/s, and reduce the critical cooling rate of martensitic from 0.4 ℃/s to 0.2 ℃/s, which improves the hardenability of steel. The test results of impact energy curves show that the first type of tempering brittleness and the second type of tempering brittleness of the two experimental steels are in the tempering temperature range of 350 ℃-500 ℃ and 550 ℃-620 ℃, respectively, and the impact energy of Ni-containing steel in the whole tempering temperature range is higher than that of Ni-free steel, indicating that Ni element can improve the hardenability of QDH steel and improve its toughness.
Ryoo D Y , Kang N , Kang C Y . Effect of Ni content on the tensile properties and strain-induced martensite transformation for 304 stainless steel [J]. Materials Science and Engineering: A , 2011 , 528 ( 6 ): 2277 - 2281 .
Jiang Q C , Sui H L , Guan Q F . Thermal fatigue behavior of new type high-Cr cast hot work die steel [J]. ISIJ International , 2004 , 44 ( 6 ): 1103 - 1107 .
Bepari M M A , Shorowordi K M . Effects of molybdenum and nickel additions on the structure and properties of carburized and hardened low carbon steels [J]. Journal of Materials Processing Technology , 2004 , 155-156 : 1972 - 1979 .
Odqvist J , Hillert M , Ågren J . Effect of alloying elements on the γ to α transformation in steel. I [J]. Acta Materialia , 2002 , 50 ( 12 ): 3213 - 3227 .
Hu Z Q , Wang K K . Investigation into the thermal stability of a novel hot-work die steel 5CrNiMoVNb [J]. High Temperature Materials and Processes , 2022 , 41 ( 1 ): 353 - 363 .
Morsdorf L , Emelina E , Gault B , et al . Carbon redistribution in quenched and tempered lath martensite [J]. Acta Materialia , 2021 , 205 : 116521 .
Lee K B , Kwon H , Kwon H , et al . Effects of alloying additions and austenitizing treatments on secondary hardening and fracture behavior for martensitic steels containing both Mo and W [J]. Metallurgical and Materials Transactions A , 2001 , 32 ( 7 ): 1659 - 1670 .
Gong W , Yue J B , Tian J L , et al . The effect of nickel on the carbide precipitation behavior in Cr-Mo-V hot-working die steel [J]. Journal of Materials Research and Technology , 2023 , 27 : 4452 - 4460 .