Main Article Content
This research aimed to investigate the microstructure modification mechanism used to improve the hardness and wear resistance of SKH51 steel. The cryogenic treatment (CT), including both shallow cryogenic treatment (SCT) and deep cryogenic treatment (DCT), was used to modify the microstructure of SKH51 steel in this research. The effect of short and long holding time (12 and 36 h) in CT was studied. The microstructures were evaluated by using a light optical microscopy (LOM) and a scanning electron microscopy (SEM). The phase identifications of the matrix, carbides, and a-parameter of the matrix were analyzed by using X-ray diffraction (XRD). The M6C and MC carbides size, aspect ratio, and distribution were analyzed using digimizer image analysis software on the SEM micrographs. Micro-Vickers were employed to evaluate the hardness of the targeted samples. Wear tests were performed by using a 6 mm diameter WC ball as the indenter and 5-N-constant load with a ball-on-disk wear tester. The results suggested that the increase of the secondary carbide was caused by the contraction and expansion phenomena of the matrix’s lattice, forcing the carbon atom out and acting as the carbide nucleation. The influence of holding time in the SCT and DCT regions was different. For the SCT, increasing the holding time increased the volume’s fraction of MC carbide. Conversely, the M6C carbide size grew with increasing holding time in the DCT region, while no significant increase in the number of MC carbide was observed. The cryogenic treatment was found to increase the volume fraction of the MC carbide by up to 10% compared to the conventional heat treatment (CHT) condition in the SCT region (both 12 and 36 h) and DCT with 12 h holding time. Due to the microstructure modification, it was found that the cryogenic treatment can improve material hardness and lead to an increase in the wear resistance of SKH51 by up to 70% compared to the CHT treated material. This was due to the increase in the compressive residual stress, precipitation of the MC, and growth of the M6C primary carbide.
F. Meng, K. Tagashira, and H. Sohma, “Wear resistance and microstructure of cryogenic treated Fe-1.4Cr-1C bearing steel,” Scripta Metallurgica et Materialia, vol. 31, no. 7, pp. 865–868, 1994, doi: 10.1016/0956-716x(94)90493-6.
P. J. Singh, B. Guha, and D. R. G. Achar, “Fatigue life improvement of AISI 304L cruciform welded joints by cryogenic treatment,” Engineering Failure Analysis, vol. 10, no.1, pp. 1–12, 2003, doi: 10.1016/s1350-6307(02)00033-x.
F. Meng, K. Tagashira, and R. S. H. Azuma, “Role of eta-carbide precipitation in the wear resistance improvements of Fe-12Cr- Mo-V-1.4C tool steel by cryogenic treatment,” ISIJ International, vol. 34, no. 2, pp. 205–210, 1994, doi: 10.2355/isijinternational.34.
F. Cajner, D. Landek, H. Rafael, S. Šolić, and S. Kovačić, “Effect of deep cryogenic treatment on dilatometric curve and tribological properties of high speed steel,” International Heat Treatment and Surface Engineering, vol. 6, no. 2, pp. 67–71, 2012. doi: 10.1179/1749514812z.000000000.
A. Razavykia, C. Delprete, and P. Baldissera, “Correlation between microstructural alteration, mechanical properties and manufacturability after cryogenic treatment: A review,” Materials, vol. 12, no. 20, 2019, doi: 10.3390/ma12203302.
D. Das, A. K. Dutta, V. Toppo, and K. K. Ray, “Effect of deep cryogenic treatment on the carbide precipitation and tribological behavior of D2 steel,” Materials and Manufacturing Processes, vol. 22, no. 4, pp. 474–480, 2007, doi: 10.1080/10426910701235934.
S. A. Chopra and V. G. Sargade, “Metallurgy behind the cryogenic treatment of cutting tools: An overview,” Materials Today: Proceedings, vol. 2, no. 4–5, pp. 1814–1824, 2015, doi: 10.1016/j.matpr.2015.07.119.
F. Diekman, “Cold and cryogenic treatment of steel,” Steel Heat Treating Fundamentals and Processes. Ohio: ASM International, 2013, pp. 382–386. https://doi.org/10.31399/asm.hb. v04a.a0005822
N. S. Kalsi, R. Sehgal, and V. S. Sharma, “Cryogenic treatment of tool materials: A review,” Materials and Manufacturing Processes, vol. 25, no. 10, pp. 1077–1100, 2010, doi: 10.1080/10426911003720862.
A. Molinari, M. Pellizzari, S. Gialanella, G. Straffelini, and K. H. Stiasny, “Effect of deep cryogenic treatment on the properties of tool steel,” Journal of Materials Processing Technology, vol. 118, no. 1–3, pp. 350–355, 2001, doi: 10.1016/s0924- 0136(01)00973-6.
V. Leskovsek and B. Ule, “Classic contributions: Cryogenic treatment Influence of deep cryogenic treatment on microstructure, mechanical properties and dimensional changes of vacuum heat-treated high-speed steel,” International Heat Treatment and Surface Engineering, vol. 29, no. 7, pp. 155– 161, 2002, doi: 10.1179/174951508x446385.
S. Li, Y. Xie, and X. Wu, “Hardness and toughness investigations of deep cryogenic treated cold work die steel,” Cryogenics, vol. 50, no. 2, pp. 89–92, 2010, doi: 10.1016/j.cryogenics. 2009.12.005.
S. Zhirafar, A. Rezaeian, and M. Pugh, “Effect of cryogenic treatment on the mechanical properties of 4340 steel,” Journal of Materials Processing Technology, vol. 186, no. 1–3, pp. 298–303, 2007, doi: 10.1016/j.jmatprotec.2006.12.
A. Idayan, A. Gnanavelbabu, and K. Rajkumar, “Influence of deep cryogenic treatment on the mechanical properties of AISI 440C bearing steel,” Procedia Engineering, vol. 97, pp. 1683– 1691, 2014, doi: 10.1016/j.proeng.2014.12.319.
J. D. Darwin, L. D. Mohan, and G. Nagarajan, “Optimization of cryogenic treatment to maximize the wear resistance of 18% Cr martensitic stainless steel by Taguchi method,” Journal of Materials Processing Technology, vol. 195, no. 1–3, pp. 241–247, 2008, doi: 10.1016/j. jmatprotec.2007.05.005.
K. Moore and D. N. Collins, “Cryogenic treatment of three heat-treated tool steels,” Key Engineering Materials, vol. 86–87, no. 47–54, pp. 47–54, 1993, doi: 10.4028/www.scientific.net/kem.86- 87.47.
R. F. Barron and C. R. Mulhern, “Cryogenic treatment of AISI-T8 and C1045 steels,” Advances in Cryogenic Engineering Materials, pp. 171– 179, 1980, doi: 10.1007/978-1-4613-9859-2_17.
L. D. Mohan, S. Renganarayanan, and A. Kalanidhi, “Cryogenic treatment to augment wear resistance of tool and die steels,” Cryogenics, vol. 41, no. 3, pp. 149–155, 2001. doi: 10.1016/s0011-2275 (01)00065-0.
F. J. D. Silva, S. D. Franco, Á. R. Machado, E. O. Ezugwu, and A. M. Souza, “Performance of cryogenically treated HSS tools,” Wear, vol. 261, no. 5–6, pp. 674–685, 2006, doi: 10.1016/j. wear.2006.01.017.
V. Leskovšek and B. Ule, “Classic contributions: Cryogenic treatment Influence of deep cryogenic treatment on microstructure, mechanical properties and dimensional changes of vacuum heat-treated high-speed steel,” International Heat Treatment and Surface Engineering, vol. 3, no. 3–4, pp. 155– 161, 2008, doi: 10.1179/174951508x446385.
I. Alexandru, C. Picos, and G. Ailincai, “Contributions on the study of the increase of durability of the high-alloyed tool steels by thermal treatments at cryogenic temperatures,” in 2nd International Congress on Heat Treatment of Materials, 1982, pp. 573–579.
R. Kelkar, P. Nash, and Y. Zhu, “Understanding the effects of cryogenic treatment on M2 tool steel properties,” Heat Treating Progress, vol. 7, no. 5, pp. 57–60, 2007.
P. Jurci, A. Bartkowska, M. Hudáková, M. Dománková, M. Caplovicová, and D. Bartkowski, “Effect of sub-zero treatments and tempering on corrosion behaviour of Vanadis 6 tool steel,” Materials, vol. 14, p. 3759, 2021, doi: https://doi. org/10.3390/ma14133759.
N. Xu, G. P. Cavallaro, and A. R. Gerson, “Synchrotron micro-diffraction analysis of the microstructure of cryogenically treated high performance tool steels prior to and after tempering,” Materials Science and Engineering: A, vol. 527, no. 26, pp. 6822–6830, 2010, doi: 10.1016/j. msea.2010.06.072.
K. Tanaka, “X-ray measurement of triaxial residual stress on machined surfaces by the cosα method using a two-dimensional detector,” Journal of Applied Crystallography, vol. 51, no. 5, pp. 1329–1338, 2018, doi: 10.1107/ s1600576718011056.
R. J. Bayer, Mechanical Wear Fundamentals and Testing. Florida: CRC Press, 2004.
M. M. Serna and J. L. Rossi, “MC complex carbide in AISI M2 high-speed steel,” Materials Letters, vol. 63, no. 8, pp. 691–693, 2009, doi: 10.1016/j.matlet.2008.11.035.
X. Zhou, F. Fang, G. Li, and J. Jiang, “Morphology and properties of M2C eutectic carbides in AISI M2 steel,” ISIJ International, vol. 50, no. 8, pp. 1151– 1157, 2010, doi: 10.2355/isijinternational. 50.
H. Qua, B. Liao, L. Liu, D. Li, J. Guoa, X. Renc, and Q. Yang, “Precipitation rule of carbides in a new high speed steel for rollers,” Calphad, vol. 36, pp. 144–150, 2012, doi: 10.1016/j.calphad. 2011.06.006.
H. E. Townsend, “Effect of alloying elements on the corrosion of steel in industrial atmospheres,” Corrosion, vol. 57, no. 6, pp. 497–501, 2001, doi: 10.5006/1.3290374.
V. G. Pleshivtsev, G. A. Filippov, Y. A. Pak, and O. V. Livanova, “Effect of carbon content and stressed state on the corrosion rate of pipe steel in heating systems,” Metallurgist, vol. 53, no. 7–8, pp. 502–505, 2009, doi: 10.1007/s11015- 009-9188-2.
N. Wannaprawat and K. Tuchinda, “Influence of deep cryogenic treatment on microstructure, hardness, impact strength and wear of CuBeZr Alloy,” Chiang Mai Journal of Science, vol. 48, no. 2, pp. 631–647, 2021.
M. Boccalini and H. Goldenstein, “Solidification of high speed steels,” International Materials Reviews, vol. 46, no. 2, pp. 92–115, 2001, doi: 10.1179/095066001101528411.
H. F. Fischmeister, R. Riedl, and S. Karagöz, “Solidification of high-speed tool steels,” Metallurgical Transactions A, vol. 20, no. 10, pp. 2133–2148, 1989, doi: 10.1007/bf02650299.
D. Gantenbein, J. Schoelkopf, G. P. Matthews, and P. A. C. Gane, “Determining the size distribution-defined aspect ratio of rod-like particles,” Applied Clay Science, vol. 53, no. 4, pp. 538–543, 2011, doi: 10.1016/j. clay.2011.01.034.
X. Gao, T. Wang, and J. Kim, “On ductile fracture initiation toughness: Effects of void volume fraction, void shape and void distribution,” International Journal of Solids and Structures, vol. 42, no. 18–19, pp. 5097–5117, 2005, doi: 10.1016/j.ijsolstr.2005.02.02.
X. Yuan and Y. Ji, “Characterization and analysis of the aspect ratio of carbide grains in WC-Co composites,” RSC Advances, vol. 8, no. 60, pp. 34468–34475, 2018, doi: 10.1039/c8ra03186j.
V. A. Lobodyuk, Y. Y. Meshkov, and E. V. Pereloma, “On tetragonality of the martensite crystal lattice in steels,” Metallurgical and Materials Transactions A, vol. 50, pp. 97–103, 2018, doi: 10.1007/s11661-018-4999-z.
X. Zhou, D. Liu, W. L. Zhu, F. Fang, Y. Y. Tu, and J. Q. Jiang, “Morphology microstructure and decomposition behavior of M2C carbides in high speed steel,” Journal of Iron and Steel Research, vol. 24, no. 1, pp. 43–49, 2017, doi: 10.1016/s1006-706x(17)30007-9.
D. Das, A. K. Dutta, V. Toppo, and K. K. Ray, “Effect of deep cryogenic treatment on the carbide precipitation and tribological behavior of D2 steel,” Materials and Manufacturing Processes, vol. 22, no. 4, pp. 474–480, 2007, doi: 10.1080/ 10426910701235934.