PREDICTION OF AZ91 CASTING MISRUNS AND ALLOY FLUIDITY USING NUMERICAL SIMULATION
https://doi.org/10.17073/0021-3438-2018-5-31-38
Abstract
Prediction of the misrun formation in thin-walled castings of magnesium alloys is a crucial task for foundry. The computer simulation of the casting processes can be used to solve this problem. A reasonable simulation results requires the correct thermal properties of the alloy and the mold over a wide range of temperatures and the value of interfacial heat transfer coefficient between the casting and the mold, and the critical solid fraction at which the alloy flow in the mold is choked off. In this paper we determine the interfacial heat transfer coefficient between the magnesium alloy ML5 (AZ91) and the sand mold with a furan binder. It was done by the comparing the simulated spiral test lengths with the experimental spiral test lengths obtained under the same conditions. Above the liquidus temperature the interfacial heat transfer coefficient IHTCL = 1500 W/(m2 ·K) at pouring temperatures 670 and 740 °С and IHTCL = 1800 W/(m2 ·K) at pouring temperature 810 °С. Below the solidus temperature the interfacial heat transfer coefficient IHTCS = 600 W/(m2 ·K). We also determined the critical solid fraction of ML5 (AZ91) magnesium alloy for the casting made in the furan bonded sand mold (at a cooling rate ~2 K/s) and it was 0.1–0.15. We compared the simulated misruns position and the experimental misrun position in the «Protective cup» casting produced from the ML5 (AZ91) alloy into the sand mold with furan binder. The value of the critical solid fraction was clarified. The castings were made at pouring temperatures 630 and 670 °C, and the critical solid fraction was 0.1 in both cases.
About the Authors
A. V. Petrova
National University of Science and Technology (NUST) «MISIS»
Russian Federation
Russian Federation
postgraduate student, Department of foundry technologies and material art working (FT&MAW),
119049, Moscow, Leninskii pr., 4
V. E. Bazhenov
National University of Science and Technology (NUST) «MISIS»
Russian Federation
Russian Federation
Cand. Sci. (Tech.), assistant prof., Department of FT&MAW,
119049, Moscow, Leninskii pr., 4
A. V. Koltygin
National University of Science and Technology (NUST) «MISIS»
Russian Federation
Russian Federation
Cand. Sci. (Tech.), assistant prof., Department of FT&MAW,
119049, Moscow, Leninskii pr., 4
References
1. Jakumeit J., Subasic E., Bünck M. Prediction of misruns in thin wall castings using computational simulation. In: Shape Casting: 5th Intern. Symp. San Diego: John Wiley & Sons, 2014. P. 253—260.
2. Humphreys N.J., McBride D., Shevchenko D.M., Croft T.N., Withey P., Green N.R., Cross M. Modelling and validation: Casting of Al and TiAl alloys in gravity and centrifugal casting processes. Appl. Math. Model. 2013. Vol. 37. No. 14—15. P. 7633—7643.
3. Di Sabatino M., Arnberg L. A review on the fluidity of Al based alloys. Metall. Sci. Technol. 2004. Vol. 22. No. 1. P. 9—15.
4. Пикунов М.В. Плавка металлов, кристаллизация сплавов, затвердевание отливок: Учеб. пос. для вузов. М.: МИСиС, 2005; Pikunov M.V. Plavka metallov, kristallizatsiya splavov, zatverdevanie otlivok [Melting of alloys, alloys crystallization, solidification of castings]. Moscow: MISIS, 2005.
5. Di Sabatino M., Arnberg L., Brusethaug S., Apelian D. Fluidity evaluation methods for Al—Mg—Si alloys. Int. J. Cast Met. Res. 2006. Vol. 19. P. 94—97.
6. Li Y., Wu G., Chen A., Liu W., Wang Y., Zhang L. Effects of processing parameters and addition of flame-retardant into moulding sand on the microstructure and fluidity of sand-cast magnesium alloy Mg—10Gd—3Y—0.5Zr. J. Mater. Sci. Technol. 2017. Vol. 33. No. 6. P. 558—566.
7. Hua Q., Gao D., Zhang H., Zhang Y., Zhai Q. Influence of alloy elements and pouring temperature on the fluidity of cast magnesium alloy. Mater. Sci. Eng. A. 2007. Vol. 444. No. 1—2. P. 69—74.
8. Колтыгин А.В., Плисецкая И.В. Влияние малых добавок кальция на жидкотекучесть магниевых сплавов. Литейщик России. 2011. No. 6. С. 41—43; Koltygin A.V., Plisetskaya I.V. Vliyanie malykh dobavok kal’tsiya na zhidkotekuchest’ magnievykh splavov [Influence of low calcium additions on fluidity of magnesium alloys]. Liteishchik Rossii. 2011. No. 6. P. 41—43.
9. Ravi K.R., Pillai R.M., Amaranathan K.R., Pai B.C., Chakraborty M. Fluidity of aluminum alloys and composites: A review. J. Alloys Compd. 2008. Vol. 456. No. 1—2. P. 201—210.
10. Dahle A.K., Arnberg L. Development of strength in solidifying aluminium alloys. Acta Mater. 1997. Vol. 45. No. 2. P. 547—559.
11. Veldman N.L., Dahle A.K., StJohn D.H., Arnberg L. Dendrite coherency of Al—Si—Cu alloys. Metall. Mater. Trans. A. 2001. Vol. 32. No. 1. P. 147—155.
12. Dahle A.K., Tшndel P.A., Paradies C.J., Arnberg L. Effect of grain refinement on the fluidity of two commercial Al— Si foundry alloys. Metall. Mater. Trans. A. 1996. Vol. 27. No. 8. P. 2305—2313.
13. Król M., Tański T., Matula G., Snopiński P., Tomiczek A.E. Analysis of crystallisation process of cast magnesium alloys based on thermal derivative analysis. Arch. Metall. Mater. 2015. Vol. 60. No. 4. P. 2993—2999.
14. Liang S.M., Chen R.S., Blandin J.J., Suery M., Han E.H. Thermal analysis and solidification pathways of Mg— Al—Ca system alloys. Mater. Sci. Eng. A. 2008. Vol. 480. No. 1—2. P. 365—372.
15. Gourlay C.M., Meylan B., Dahle A.K. Shear mechanisms at 0—50% solid during equiaxed dendritic solidification of an AZ91 magnesium alloy. Acta Mater. 2008. Vol. 56. No. 14. P. 3403—3413.
16. Gourlay C.M., Meylan B., Dahle A.K. Rheological transitions at low solid fraction in solidifying magnesium alloy AZ91. Mater. Sci. Forum. 2007. Vol. 561—565. P. 1067—1070.
17. Hou D.-H., Liang S.-M., Chen R.-S., Dong C., Han E.-H. Effects of Sb content on solidification pathways and grain size of AZ91 magnesium alloy. Acta Metall. Sinica (Engl. Lett.). 2015. Vol. 28. No. 1. P. 115—121.
18. Barber L.P. Characterization of the solidification behavior and resultant microstructures of magnesium-aluminum alloys: A Master degree thesis. Worchester: Worchester Polytechnic Institute, 2004.
19. Rajaraman R., Velraj R. Comparison of interfacial heat transfer coefficient estimated by two different techniques during solidification of cylindrical aluminum alloy casting. Heat and Mass Transfer. 2008. Vol. 44. No. 9. P. 1025—1034.
20. Chen L., Wang Y., Peng L., Fu P., Jiang H. Study on the interfacial heat transfer coefficient between AZ91D magnesium alloy and silica sand. Exp. Thermal and Fluid Sci. 2014. Vol. 54. P. 196—203.
21. Wang D., Zhou C., Xu G., Huaiyuan A. Heat transfer behavior of top side-pouring twin-roll casting. J. Mater. Process. Technol. 2014. Vol. 214. No. 6. P. 1275—1284.
22. Griffiths W., Kawai K. The effect of increased pressure on interfacial heat transfer in the aluminium gravity die casting process. J. Mater. Sci. 2010. Vol. 45. No. 9. P. 2330— 2339.
23. Sun Z., Hu H., Niu X. Determination of heat transfer coefficients by extrapolation and numerical inverse methods in squeeze casting of magnesium alloy AM60. J. Mater. Process. Technol. 2011. Vol. 211. No. 8. P. 1432—1440.
24. Nishida Y., Droste W., Engler S. The air-gap formation process at the casting-mold interface and the heat transfer mechanism through the gap. Metall. Trans. B. 1986. Vol. 17. No. 4. P. 833—844.
25. Тихомиров М.Д. Моделирование тепловых и усадочных процессов при затвердевании отливок из высокопрочных алюминиевых сплавов и разработка системы компьютерного анализа литейной технологии: Автореф. дис. … канд. техн. наук. СПб.: СПбГПУ, 2004; Tikhomirov M.D. Modelirovanie teplovykh i usadochnykh protsessov pri zatverdevanii otlivok iz vysokoprochnykh alyuminievykh splavov i razrabotka sistemy komp’yuternogo analiza liteinoi tekhnologii [Simulation of thermal and shrinkage processes during solidification and developing of computer analysis model of casting technology]: Abstract of the dissertation of PhD. St. Petersburg: SPbSPU, 2004.
26. Bouchard D., Leboeuf S., Nadeau J.P., Guthrie R.I.L., Isac M. Dynamic wetting and heat transfer at the initiation of aluminum solidification on copper substrates. J. Mater. Sci. 2009. Vol. 44. No. 8. P. 1923—1933.
27. Lu S.-L., Xiao F.-R., Zhang S.-J., Mao Y.-W., Liao B. Simulation study on the centrifugal casting wet-type cylinder liner based on ProCAST. Appl. Thermal Eng. 2014. Vol. 73. No. 1. P. 512—521.
28. Di Sabatino M., Arnberg L., Bonollo F. Simulation of fluidity in Al—Si alloys. Metall. Sci. Technol. 2005. Vol. 23. No. 1. P. 3—10.
29. Bazhenov V.E., Petrova A.V., Koltygin A.V. Simulation of fluidity and misrun prediction for the casting of 356.0 aluminum alloy into sand molds. Int. J. Metalcasting. 2018. Vol. 12. No. 3. P. 514—522. https://doi.org/10.1007/ s40962-017-0188-x
30. Palumbo G., Piglionico V., Piccininni A., Guglielmi P., Sorgente D., Tricarico L. Determination of interfacial heat transfer coefficients in a sand mould casting process using an optimised inverse analysis. Appl. Thermal Eng. 2015. Vol. 78. P. 682—694.
31. Жмуриков Е.И., Савченко И.В., Станкус С.В., Tecchio L. Измерения теплофизических свойств графитовых композитов для конвертора нейтронной мишени. Вестн. НГУ. Сер. Физика. 2011. Том. 6. No. 2. С. 77—84; Zhmurikov E.I., Savchenko I.V., Stankus S.V., Tecchio L. Izmereniya teplofizicheskikh svoistv grafitovykh kompozitov dlya konvertora neitronnoi misheni [Measurements of thermal properties of graphite composites for neutron target converter]. Vestnik NGU. Ser. Fizika. 2011. Vol. 6. No. 2. P. 77—84.
32. Баженов В.Е., Колтыгин А.В., Целовальник Ю.В., Санников А.В. Определение коэффициентов теплопередачи и теплоотдачи для моделирования процесса литья алюминия в графитовые формы. Изв. вузов. Цвет. металлургия. 2017. No. 1. С. 40—52; Bazhenov V.E., Koltygin A.V., Tselovalnik Yu.V., Sannikov A.V. Determination of interface heat transfer coefficient between aluminum casting and graphite mold. Russ. J. Non-Ferr. Met. 2017. Vol. 58. No. 2. P. 114—123.
33. Баженов В.Е., Петрова А.В., Колтыгин А.В., Целовальник Ю.В. Определение коэффициента теплопередачи между отливкой из сплава МЛ5пч (AZ91) и формой из холоднотвердеющей смеси. Цвет. металлы. 2017. No. 8. С. 89—96; Bazhenov V.E., Petrova A.V., Koltygin A.V., Tselovalnik Yu.V. Opredelenie koeffitsienta teploperedachi mezhdu otlivkoi iz splava ML5pch (AZ91) i formoi iz kholodnotverdeyushchei smesi [Determination of heat transfer coefficient between AZ91 magnesium alloy casting and no-bake mold]. Tsvetnye Metally. 2017. No. 8. P. 89—96.
Review
For citations:
Petrova A.V., Bazhenov V.E., Koltygin A.V. PREDICTION OF AZ91 CASTING MISRUNS AND ALLOY FLUIDITY USING NUMERICAL SIMULATION. Izvestiya. Non-Ferrous Metallurgy. 2018;(5):31-38. (In Russ.) https://doi.org/10.17073/0021-3438-2018-5-31-38
Views:
761
Email this article 