Abstract：In order to investigate effects of different tempering processes on microstructure and properties of bearing steel 440C, effects of spheroidizing annealing-quenching-tempering process and spheroidizing annealing-quenching-tempering-cold treatment-tempering process on microstructure and properties of bearing steel 440C containing Ce were studied by means of SEM, XRD and TEM. The quenching temperature was 1 050 ℃, tempering temperature was 200 ℃ and cold treatment temperature was -78.5 ℃. The results show that the phase of steel is martensite + retained austenite + M23C6 carbide under the two processes. Compared with only spheroidizing annealing-quenching-tempering, the volume fraction of retained austenite in the test steel decreases from 11.06% to 7.63%, the size and quantity of primary carbides remain unchanged, the number of secondary carbides increases by 49.4%, and the average area decreases by 24.0% under the process conditions of spheroidizing annealing-quenching-tempering-cold treatment-tempering. In the aspect of mechanical properties, the impact energy increase from 90.5 J to 115.0 J, and the elongation after fracture increases from 5.3% to 8.3%. However, the tensile strength increases from 2 039.24 MPa to 2 060.14 MPa, and the Rockwell hardness increases from 58.70HRC to 59.09HRC. The transformation of mechanical properties is attributed to the combined action of microstructure and carbide. Under the experimental conditions, the spheroidizing annealing-quenching-tempering-cold treatment-tempering process is more beneficial to the improvement of toughness and plasticity of 440C bearing steel, but limited to the improvement of strength and hardness. This study provides a reference for the design of tempering process of 440C bearing steel.
马帅, 李阳, 姜周华, 孙萌, 毛昀惬, 马彦硕. 回火工艺对含Ce轴承钢440C组织性能影响[J]. 中国冶金, 2023, 33(8): 61-69.
MA Shuai, LI Yang, JIANG Zhouhua, SUN Meng, MAO Yunqie, MA Yanshuo. Effect of tempering process on microstructure and properties of bearing steel 440C containing Ce[J]. China Metallurgy, 2023, 33(8): 61-69.
LIU F B, FU G H, CUI Y, et al. Tribological properties and surface structures of ion implanted 9Cr18Mo stainless steels[J]. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2013, 307(8): 412.
CLEMONS K, LORRAINE C, SALGADO G, et al. Effects of heat treatments on steels for bearing applications[J]. Journal of Materials Engineering and Performance, 2007, 16(5): 592.
CHEN R C, WANG Z G, ZHU F S, et al. Effects of rare-earth micro-alloying on microstructures, carbides, and internal friction of 51CrV4 steels[J]. Journal of Alloys and Compounds, 2020, 824: 153849.
[8]
WANG H, HONG D, HOU L, et al. Influence of tempering temperatures on the microstructure, secondary carbides and mechanical properties of spray-deposited AISI M3: 2 high-speed steel[J]. Materials Chemistry and Physics, 2020, 255: 123554.
[9]
WENG Z, GU K, ZHENG J, et al. Cryogenically martensitic transformation and its effects on tempering behaviors of bearing steel[J]. Materials Characterization, 2022, 190:112066.
[10]
崔忠圻, 覃耀春. 金属学与热处理[M]. 哈尔滨:哈尔滨工业大学出版社, 2004.
[11]
BLASS T, DINKEL M, TROJAHN W. Bearing performance as a function of structure and heat treatment[J]. Materials Science and Technology, 2016, 32(11): 1079.
ÖZBEK N A. Effects of cryogenic treatment types on the performance of coated tungsten tools in the turning of AISI H11 steel[J]. Journal of Materials Research and Technology, 2020, 9(4): 9442.
[16]
LI S H, XIAO M G, YE G M, et al. Effects of deep cryogenic treatment on microstructural evolution and alloy phases precipitation of a new low carbon martensitic stainless bearing steel during aging[J]. Materials Science and Engineering A, 2018, 732: 167.
[17]
MEHTEDI M E, RICCI P, DRUDI L, et al. Analysis of the effect of deep cryogenic treatment on the hardness and microstructure of X30 CrMoN 15 1 steel[J]. Materials and Design, 2012, 33: 136.
[18]
AMINI K, NATEGH S, SHAFYEI A, et al. Effect of deep cryogenic treatment on the properties of 80CrMo12 5 tool steel[J]. International Journal of Minerals, Metallurgy, and Materials, 2012, 19(1): 30.
[19]
MOLINARI A, PELLIZZARI M, GIALANELLA S, et al. Effect of deep cryogenic treatment on the mechanical properties of tool steels[J]. Journal of Materials Processing Technology, 2001, 118(1/2/3): 350.
JELEN＇KOWSKI J, CISKI A, BABUL T. Effect of deep cryogenic treatment on substructure of HS6-5-2 high speed steel[J]. Journal of Achievements in Materials and Manufacturing Engineering, 2010, 43(1): 80.
[22]
NYKIEL T, HRYNIEWICZ T. Transformations of carbides during tempering of D3 tool steel[J]. Journal of materials Engineering and Performance, 2014, 23: 2050.
WANG Z, LV Z, BAI X, et al. Study on transformation characteristics of carbides in an 8%Cr roller steel[J]. Journal of Materials Science, 2012, 47(20): 7132.
XIAO M G, LV X Y, LI D H, et al. Strengthening and toughening mechanisms of high Cr-Co-Mo heat resistant bearing steel[J]. Transactions of Materials and Heat Treatment, 2018, 39(9):52.
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