This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Effects of Silicon and Boron Additions on the Susceptibility to Quench Embrittlement and the Bending Fatigue Performance of Vacuum Carburized Modified 4320 Steel
Technical Paper
2007-01-1005
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
The effect of B and Si additions on fracture and fatigue performance of vacuum carburized 4320 steel and modifications of 4320 steel containing additions of Si (1.0 and 2.0 wt pct) and B (0 and 17 ppm) was evaluated by bending fatigue testing. Three rates of gas quenching, in 10 bar nitrogen and 15 and 20 bar helium, were used to cool specimens after carburizing. The B, protected by Ti additions, together with the Si additions, increased core hardenability. The B/Si modified steels showed no improvement in fatigue resistance, as measured by endurance limits established by 10 million cycle runouts without fracture. However, scanning electron microscopy showed that Si reduced sensitivity to intergranular fracture or quench embrittlement, a major cause of bending fatigue crack initiation, and contributed to variable fatigue performance, with both low-cycle failures and runout performance at applied stresses significantly above measured endurance limits. The vacuum carburized steels containing 2 wt pct Si showed appreciable grain growth relative to the other steels, a result that contributed to low fatigue resistance. Results are presented and discussed relative to the effects of steel chemistry and gas quench rate during vacuum carburizing.
Recommended Content
Authors
- Jason J. Spice - Advanced Steel Processing and Products Research Center
- John G. Speer - Advanced Steel Processing and Products Research Center
- George Krauss - Advanced Steel Processing and Products Research Center
- David K. Matlock - Advanced Steel Processing and Products Research Center
- Harry Meyer - Oak Ridge National Laboratory
Citation
Spice, J., Speer, J., Krauss, G., Matlock, D. et al., "Effects of Silicon and Boron Additions on the Susceptibility to Quench Embrittlement and the Bending Fatigue Performance of Vacuum Carburized Modified 4320 Steel," SAE Technical Paper 2007-01-1005, 2007, https://doi.org/10.4271/2007-01-1005.Also In
Steel Innovations, Fatigue Research, Sheet/Hydro/Gas Forming Technology & Advanced High Strength Steel Development
Number: SP-2103; Published: 2007-04-16
Number: SP-2103; Published: 2007-04-16
References
- Wise J.P. Matlock D.K. “Bending Fatigue of Carburized Steels: A Statistical Analysis of Process and Microstructural Parameters” SAE Technical Publication No. 2000-01-0611 SAE Warrendale, PA. 2000
- Wise J.P. Matlock D.K. Krauss G. “Microstructure and Fatigue Resistance of Carburized Steels” Heat Treating: Proceedings of the 20 th Conference Funatani K. Totten G.E. ASM International Materials Park, OH 2001 2 1152 1161 “Bending Fatigue of Carburized Steels” Heat Treating Progress 1 4 Apr. 2001 33 41
- Krauss G. “Bending Fatigue of Carburized Steels” Fatigue and Fracture 19 ASM Handbook 1996 680 690
- Hyde R. S. Matlock D. K. Krauss G. “Quench Embrittlement: Intergranular Embrittlement due to Cementite and Phosphorus in Quenched Carbon and Alloy Steels 40 th MWSP Conference Proceedings ISS Warrendale, PA 1998 921 928
- Cornelissen B.E. “Alloying and Processing Approaches to Improved Bending Fatigue Performance of Carburized Gear Steels” Colorado School of Mines Golden, CO 1999
- Krauss G. “Heat Treated Martensitic Steels: Microstructural Systems for Advanced Manufacture” ISIJ International 35 1995 349 359
- Barnard S. J. Smith G. D. W. Garratt-Reed A. J. Vander Sande J. “Atom Probe Studies: (1) The Role of Si in the Tempering of Steel” Solid-Solid Phase transformations Aaronson H. I. et al TMS-AIME Warrendale, PA 1982 881 885
- Chatterjee-Fischer R. “Internal Oxidation during Carburizing and Heat Treating” Metallurgical Transactions A 9A 1978 1553 1560
- Namiki K. Hatano A. “High Tough and High Fatigue Strength Carburizing Steel” Daido Steel Co. Ltd.
- Tanigchi Y. Ihara H. “Development of High-Strength Carburized Gear Steels” Mitsubishi Motors Technology Review 2 1990 53 60
- Koyasu Y. Ochi T. Takada H. Ishikawa H. Kanisawa H. Yanase M. Naito K. “Development of Special Steel Bars and Wire Rods for High-Strength Automobile Parts” Nippon Steel Technical Report No. 53 1992 35 43
- Boron in Steel Banerji S. K. Morral J. E. TMS-AIME Warrendale, PA 1980
- Hardenability Concepts with Applications to Steel Doane D. V. Kirkaldy J. S. TMS-AIME Warrendale, PA 1978
- Hyde R. S. Krauss G. Matlock D. K. “Phosphorus and Carbon Segregation: Effects on Fatigue and Fracture of Hardened Carbon Steels” Metallurgical and Materials Transactions A 25A 1994 1229 1240
- 2004 “Standard Test Methods for Determining Average Grain Size” 267 287
- Grossmann M. A. Bain E. C. Principles of Heat Treatment Fifth American Society for Metals Metals Park, Ohio 1964
- Leslie W. C. The Physical Metallurgy of Steels McGraw-Hill Book Company 1981
- Wise J.P. Krauss G. “A Thermodynamic Approach to Eliminating Quench Embrittlement” 41 st MWSP Conf. Proc. ISS XXXVII 1999 377 385
- Cohen M. “Retained Austenite” Transactions ASM 41 1949 35
- Spice J.J. “Optimized Carburized Steel Fatigue Performance as Assessed with Gear and Modified Brugger Fatigue Test” Colorado School of Mines Golden, CO 2002
- Sanders J.A. “The Effects of Shot Peening on the Bending Fatigue Behavior of a Carburized SAE 4320 Steel” Colorado School of Mines Golden, CO 1993
- Spice J. J. “Evaluation of Silicon and Boron Additions to Reduce quench Embrittlement in Modified 4320 Carburizing Grade Steel” Colorado School of Mines Golden, CO 2006
- Krauss G. The Relationship of Microstructure to Fracture Morphology and Toughness of Hardened Hypereutectoid Steels” Case-Hardened Steels: Microstructural and Residual Stress Effects Diesburg D. E. TMS_AIME 1984 33 58
- Medlin D. Krauss G. Matlock D.K. Burris K. Slane M. “Comparison of Single Gear Tooth and Cantilever Beam Bending Fatigue Testing of Carburized Steel” SAE Technical Paper Series, No. 950212 March 1995