Physical phenomena in non-ferrous casting: hot tearing, continuous casting, EB melting and refining, vaccuum casting, finite element-based heat flow and stress codes, optimization of industrial casting processes, mathematical modeling
Current Research Work
Thus far, my work has adopted an approach that combines both industrial and laboratory experiments with mathematical modeling. General finite element-based heat flow and stress codes have been developed in-house and applied, together with commercial codes, in the analysis, optimization and design of a number of industrial processes, focusing principally on casting technology. In the last 6 years I have received substantial support from industry for my effort as either the primary or co-investigator.
The expertise in heat transfer extends beyond the basics of heat conduction to include inverse conduction techniques, which have been applied to analyse complex industrial boundary conditions, solidification microstructure evolution in cast irons, freckle formation in nickel-based superalloys and hydrogen-based porosity formation in aluminum alloys . In the case of my thermal stress analysis activities, most of the effort has been directed toward the prediction of stress and strain evolution in casting processes with a view to reducing cracking and distortion and has involved both elastic and inelastic deformation. For example, a significant effort recently has been directed toward understanding and predicting the formation of hot tears in aluminum ingots that develop during the start-up phase of the direct-chill (DC) casting process and to understand mechanistically why some alloys are more sensitive to cracking than others (the DC casting process is the dominant industrial process used to produce aluminum sheet ingots).
Laboratory and industrial measurements continue to play a large role in my activities since, in many instances, the knowledge necessary to develop sophisticated process models does not exist within the literature. The data collected represents new knowledge and includes data related to heat transfer phenomena , data related to distortion phenomena data related to porosity formation, data related to the constitutive behaviour of alloys at high temperature, including in the semi-solid state , data related to defect formation in nickel-based superalloys and data related to the evolution in the solidification structure in various aluminum alloys . The collection of this data often represents a significant challenge and requires the use of sophisticated state-of-the art equipment and techniques. The industrial data in particular is often very difficult to acquire because of the need to work on production equipment, but is unique and often essential to our understanding of how these processes operate mechanistically.
As evidence of impact, many of the codes for which I have coordinated the development are actively in use by industry. Specifically, the code developed for Canadian Autoparts Toyota Inc. is being used in the design of die-tooling for the production of aluminum alloy wheels; the code developed for the TIMKEN Company is being utilized in the thermal-mechanical processing of steel tubing; and the code developed for Alcan Ltd. is being applied to optimize the casting recipe used during the start-up phase of the DC casting process. These are major international corporations with a significant impact on the global economy.
Primary collaborators: Dr. Daan Maijer (UBC), Dr. Mary Wells (Waterloo), Canadian Auto Part Toyota, Rio Tinto Alcan, The Timken Company.
MTRL 278 Engineering Materials
MTRL 340 Manufacturing in Materials Engineering
MTRL 515 Advanced Simulation and Modelling Tools for Materials Manufacturing
Refereed Journal Publications
Jianglan Duan, Carl Reilly, Daan M. Maijer, Steve L. Cockcroft, Andre B. Phillion , “Development of an Optimization Methodology for the Aluminum Alloy Wheel Casting Process”, Accepted for publication Metallurgical and Materials Transactions B, March, 2015.
Jun Ou, Steve L. Cockcroft, Daan M. Maijer, Lu Yao, Carl Reilly, Ainual Akhtar, “An Examination of the Factor Influencing the Melting of Solid Titanium in Liquid Titanium”, Accepted International Journal of Heat and Mass Transfer, February 2015.
Jun Ou, Aniruddha Chatter jee, Steve L. Cockcroft, Daan M. Maijer, Carl Reilly and Lu Yao, “Study of Melting Mechanism of a Solid in a Liquid Metal”, International lJournal of Heat and Mass Transfer, Volume 80 pp386-97, published on-line Oct. 2014.
Farzaneh Farhang Mehr, Carl Reilly, Steve Cockcroft, Daan Maijer and Robert MacKay, ‘The effect of chill cooling conditions on the cooling rate, microstructure and casting/chill interfacial heat transfer coefficient for sand-cast A319 alloy”, International Journal of Cast Metals Research, Vol. 27, Issue 5, Oct 2014, pp 288-300.
Ligiang Zhang, Carl Reilly, Luoxing Li, Steve Cockcroft and Lu Yao, “Development of an inverse heat conduction model and its application to determination of heat transfer coefficient during casting solidification”, Journal of Heat and Mass Transfer , Vol. 50, 2014, pp. 945-955.
X. Zhao, C. Reill y, L. Yao, D. M. Mai jer, S. Cockcroft and J. Zhu, “A Three Dimensional Steady State Thermal Fluid Model of Jumbo Ingot Casting during Electron Beam Re-melting of Ti-6Al-4V”, Journal of Applied Mathematica Modeling, Published on-line, Vol. 38, Issue 15, July 2014, E . 3607-3623.
C. Reilly, J. Duan, L. Yao, D.M. Maijer, S.L. Cockcroft, “Process Modeling of Low Pressure Die Casting of Aluminum Alloy Wheels”, The Journal of the Minerals, Metals and Materials Society, Vol. 65, (9), June 2013, pp. 1111-1121.
J. Duan, D. M. Maijer, S.L. Cockcroft, C. Reilly, “Development of a 3-D Filling Model of Low-pressure Die-Cast Aluminum Alloy Wheels”, Metallurgical and Materials Transactions A., Vol. 44, (12), Dec. 2013, pp. 5304-5315.
S. Kim K.A. Khalil, S.L. Cockcroft, D. Hui, J, Hee Lee, “Sintering Behavior and Mechanical Properties of HA-Xo/o Mol 3YSZ Composites Sintered by High Frequency Induction Heat Sintering”, Composite Part B; Engineering, Vol. 45, (1), February 2013, pp. 1689-1693
L. Yao, C. Reilly, S.L. Cockcroft, “Factors Effecting Nucleation Kinetics during Micro-Porosity Formation in A356 Aluminum Alloy Castings”, Metallurgical and Materials Transactions A., Vol. 43A, (3), March 2012, pp.1004-1016.
Lu Yao, Steve Cockcroft, Jindong Zhu and Carl Reilly, “Modeling of Microporosity Size Distribution in Alloy A356”, Metallurgical and Materials Transactions A, Vol. 42A, (13), December 2011, pp. 4137-4148.
S. Kim, S.L. Cockcroft K.A. Khalil and K.Ogi, “Sintering Behaviour of Ultra-Fine Al203-(Zr02+Xmol% Y203) Ceramics by High-Frequency Induction Heating”, Materials Science and Engineering A, Vol. 527, (18-19), July 2010, pp. 4926-4931.
H. Hao, D. M. Maijer, M. A. Wells, Andre Phillion and S.L. Cockcroft, “Modeling the Stress-Strain Behavior and Hot Tearing During Direct Chill Casting of an AZ31 Magnesium Billet”, Metallurgical and Materials Transactions A, Vol. 41, (8), August 2010, pp. 2067-2077.
H. Teng, X. Zhang, Z. Zhang, T. Li, S. Cockcroft, “Research on microstructures of sub-rapidly cooled AZ61 Magnesium Alloy”, Materials Characterization, Vol. 60, (6), June 2009, pp. 482-486.
S. Kim, S.L. Cockcroft, A.M. Ornran and Honam Hwang, “Mechanical, wear and heat exposure properties of compacted graphite cast iron at elevated temperatures”, accepted for publication in Journal of Alloys and Compounds, 2009, Vol. 487 (2009) 253-257
A. B. Phillion, S. L. Cockcroft, and P. D. Lee, “Predicting the constitutive behavior of semi-solids via a direct finite element simulation: application to AA5182”, Modelling Simul. Mater. Sci. Eng., 17 (2009) 05501 l (15 pages).
0. Lashkari, L. Yao, S.L. Cockcroft, D.M. Maijer, “X-Ray Microtomographic Characterization of Porosity in Aluminum Alloy A356”, Metallurgical and Materials Transactions A: Volume 40, Issue 4 (2009), Page 991.
K. Hu, A.B. Phillion, D.M. Maijer, S.L. Cockcroft “Constitutive behavior of as-cast magnesium alloy Mg-Al3-Zn l in the semi-solid state” Scripta Mater. 60(6): 427-430 (March 2009).
A. B. Phillion, S. Verne’de, M. Rappaz, S. L. Cockcroft and P. D. Lee, “Prediction of solidification behaviour via microstructure models based on granular structures”, International Journal of Cast Metals Research, 22 ( 1-4), 2009, 240-243.
S. Kim, S.L. Cockcroft and A.M. Ornran, “Optimization of the Process Parameters Affecting the Microstructures and Properties of Compacted Graphite Iron” Journal of Alloys and Compounds, Vol. 476 12 May (2009), 728-732.
AB. Phillion, S. Thompson, S. L. Cockcroft and M. A Wells, “Tensile Properties of As-Cast Aluminum Alloys AA3104, AA611 l and CA31218 at Above Solidus Temperatures”, Mater. Sci. Eng. A., 497: 388-394:2008.
AB. Phillion, P.D. Lee, E. Maire and S.L. Cockcroft, “Quantitative assessment of deformation-induced damage in a semi-solid aluminum alloy via x-ray tomography”. Metallurgical and Materials Transactions A, Vol. 39A, Oct., 2459-2469:2008.
AB. Phillion, S.L. Cockcroft, and P.D. Lee, “A Three-phase simulation of the effect of microstructural features on semi-solid tensile deformation”, Acta Materialia 56 4328-4338(2008).
AB. Phillion, S.L. Cockcroft, R.C. Atwood, and P.D. Lee, “A New Methodology for Measurement of Semi-Solid Constitutive Behaviour and its Application to Examination of As-Cast Porosity and Hot Tearing in Aluminum Alloys”, Materials Science and Engineering A 491 (2008) 237-247.
D. Li, M.A. Wells, S.L. Cockcroft and E. Caron, Metallurgical and Materials Transactions B-Process Metallurgy and Materials Processing Science, Vol. 38, (6) 2007, pp. 901-910.
Refereed Conference Proceedings
Farzaneh Farhang Mehr, Steve Cockcroft , Carl Reilly, Daan Maijer, Evaluation of the Casting/Chill Interface Thermal Behaviour during A319 Allo y Sand Casting Process , TMS 2015 Conference Proceedings, March 15-19, Walt Disney World, Orlando, FL, USA.
J. Ou, S. Cockcroft, D. Maijer, L.Yao, C. Reilly, A. Akhtar, “A Coupled Thermal Fluid Flow- Multicomponent Model to Simulate the Melting/Dissolution of Solid Ti Al in Liquid Titanium during Electron Beam Melting”, Light Metals Production, The 53rd Annual Conference of Metallurgists (COM), Vancouver, Sep. 28 – Oct. 1, 2014.
H. Khadivinassab, P. Fan, C. Reilly, L. Yao, D.M. Maijer, S.L. Cockcroft and A.B. Phillion , “STUDY OF THE MACRO-SCALE SOLUTE REDISTRIBUTION DUE TO LIQUID METAL FEEDING DURING THE SOLIDIFICATION OF A356”, Light Metals Production, Processing and Applications Symposium, The 53rd Annual Conference of Metallurgists (COM), Vancouver, Sep. 28 – Oct. 1, 2014.
J. Duan, C. Reilly, D. Maijer, S. Cockcroft, A. Phillion, “Optimization of Die Cooling in the Aluminum Alloy Wheel Casting Process”, Advances in Materials Manufacturing Symposium, The 53rd Annual Conference of Metallurgists (COM), Vancouver, Sep. 28 – Oct. 1, 2014.
F. Sheykh jaberi, A. Phillion, S. Cockcroft, “A Coupled Fluid/Structure Simulation ot Semi-Solid Deformation in an A356 Aluminum Alloy”, Light Metals Production , Processing and Applications Symposium, The 53rd Annual Conference of Metallurgists (COM), Vancouver, Sep. 28 – Oct. 1, 2014.
Jun Ou, Steve Cockcroft, Daan Maijer, Lu Yao, Carl Reilly, Ainul Akhtar , “An Examination of the Thermally Related Factors Influencing the Melting/Dissolution of Solids in Liquid Titanium.” for potential inclusion in the proceedings Supplemental UE: TMS 2014 Conference Proceedings, San Diego, California.
R. Shuster, C. Reilly, D. M. Maijer and S.L.Cockcroft, “Modeling and Optimization of Ti-6Al-4V Ingot Production“, 13th Intl. Conf. on Modeling of Casting, Welding and Solidification Proc. (2012), ed. by Andreas Ludwig.
N. Jamaly, A.B. Phillion, S.L. Cockcroft and J.-M Drezet, “Hot Tearing Susceptability in DC Cast Aluminum Alloys”, CPE: Defects and Properties of Cast Metals, 2012 TMS Annual Meeting and Exhibition, March 11-15, Orlando Florida, Eds. Mark Jolly, Brian Thomas and Carl Reilly.
J. Duan, D. M. Maijer, S.L. Cockcroft, C. Reilly, K. Nguyen, D. Au, “Modeling of Die Filling of Low-Pressure Die-Cast Aluminum Alloy Wheels, CPE: Defects and Properties of Cast Metals, Supplemental Proceedings Volume 2: Material Properties , Characterization and Modeling, TMS, pp. 177-184, March 2012.
J. Ou, A. Chatterjee, C. Reilly, D.M.Maijer and S.L. Cockcroft, “Computational Modeling of the Dissolution of Alloying Elements”, Supplemental Proceedings Volume 1: Materials Processing and Interfaces, TMS, pp. 871-878, March 2012.
Centre for Metallurgical Process Engineering