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3D 샌드 프린팅을 이용한 금속 주조용 신규 스프루 설계

연구 목적

  • 본 연구는 **3D 샌드 프린팅(3DSP)**을 활용하여 주조 스프루(sprue) 설계를 최적화하고, 금속 용탕 흐름을 개선하는 방법을 분석함.
  • 전통적 주조 유체역학 원리를 기반으로 컴퓨터 유체 역학(CFD) 모델을 개발하여, 스프루 설계에 따른 용탕 흐름 특성과 주조 결함 감소 효과를 평가함.
  • 세 가지 스프루 설계(직선 스프루, 포물선 스프루, 원뿔형 나선 스프루)를 비교 분석하여 최적 형상을 도출함.
  • 실험 및 FLOW-3D® 시뮬레이션을 통해 스프루 최적화가 기계적·야금학적 성능 향상에 미치는 영향을 검증함.

연구 방법

  1. 스프루 설계 및 최적화
    • 직선 스프루(Straight Sprue Casting, SSC), 포물선 스프루(Parabolic Sprue Casting, PSC), 원뿔형 나선 스프루(Conical-Helix Sprue Casting, CHSC) 세 가지 설계를 비교함.
    • 최적화 알고리즘을 적용하여 유체 흐름 및 산화물 형성 최소화 조건을 도출함.
    • FLOW-3D® CFD 시뮬레이션을 활용하여 각 설계의 유동 속도, 난류 강도 및 충진 특성을 평가함.
  2. 실험 및 시뮬레이션 검증
    • CT(Computed Tomography) 스캔 및 SEM(주사전자현미경) 분석을 수행하여 주조 결함 및 산화물 포획 정도를 평가함.
    • ASTM E290 기준 3점 굽힘(flexural strength) 시험을 수행하여 기계적 강도를 비교함.
    • 스프루 설계 변경이 주조 결함(기포, 산화물 포함물) 및 최종 기계적 특성에 미치는 영향을 분석함.

주요 결과

  1. 유동 속도 및 충진 거동 분석
    • CHSC 및 PSC 설계가 SSC 대비 주형 충진 속도를 감소시켜 용탕 난류를 줄이는 효과가 있음.
    • CHSC 설계에서는 유동 속도가 0.5 m/s 이하로 감소하며, 이는 산화물 형성을 최소화하는 임계 속도 조건을 충족함.
    • CFD 시뮬레이션 결과, CHSC 스프루는 균일한 유동 분포를 형성하여 주조 품질을 향상시킴.
  2. 주조 결함 감소 효과
    • CT 스캔 결과, CHSC 적용 시 전체 주조 결함이 99.5% 감소, PSC 적용 시 56% 감소함.
    • SSC에서는 기포 및 산화물 포함물이 집중적으로 발생하였으나, CHSC 및 PSC에서는 이러한 결함이 현저히 감소함.
    • SEM 분석 결과, SSC 대비 PSC 및 CHSC의 산화물 포함물 영역이 각각 21%, 35% 감소함.
  3. 기계적 강도 향상
    • 3점 굽힘 시험 결과, CHSC는 SSC 대비 평균 굽힘 강도가 8.4% 증가, PSC는 4.1% 증가함.
    • CHSC 주조품에서 더 균일한 미세조직 및 결함 감소 효과가 확인됨.
    • ANOVA 통계 분석 결과, SSC와 CHSC 간 기계적 강도 차이가 통계적으로 유의미함(p = 0.045).

결론

  • 3D 샌드 프린팅을 활용한 신규 스프루 설계가 주조 품질을 향상시키는 데 효과적임.
  • 원뿔형 나선 스프루(CHSC) 설계는 용탕 난류 감소 및 산화물 포함물 저감에 가장 효과적이며, 기계적 강도를 8.4% 향상시킴.
  • CFD 시뮬레이션과 실험 데이터를 비교한 결과, 최적화된 스프루 설계가 실제 주조 성능 개선에 기여함을 확인함.
  • 향후 연구에서는 다양한 합금 및 주조 공정에 대한 적용성을 추가적으로 검토해야 함.

Reference

  1. Markets and markets, January. Metal Casting Market.: Global Forecast Until 2025,Accessible on: (2018) https://www.marketsandmarkets.com/Market-Reports/metal-casting-market-23885716.html.
  2. Pennsylvania Foundry Association, March. OSHA’S Proposed Silica Rule ThreatensFoundry Industry. Plymouth Meeting, PA, Accessible on: (2016) http://www.pfaweb.org/news/2016/3/11/oshas-proposed-silica-rule-threatens-foundryindustry-1.
  3. J. Dańko, R. Dańko, M. Holtzer, Reclamation of used sands in foundry production,Metalurgija 42 (3) (2003) 173–177.
  4. E.S. Almaghariz, B.P. Conner, L. Lenner, R. Gullapalli, G.P. Manogharan,B. Lamoncha, M. Fang, Quantifying the role of part design complexity in using 3Dsand printing for molds and cores, Int. J. Metalcast. 10 (3) (2016) 240–252.
  5. J. Wang, S.R. Sama, G. Manogharan, Re-thinking design methodology for castings:3D sand-printing and topology optimization, Int. J. Metalcast. (2018) 1–16.
  6. Chee Kai Chua, Kah Fai Leong, Zhong Hong Liu, Rapid tooling in manufacturing,Handbook of Manufacturing Engineering and Technology (2013) 1–22.
  7. P. Jain, A.M. Kuthe, Feasibility study of manufacturing using rapid prototyping:FDM approach, Procedia Eng. 63 (2013) 4–11.
  8. J. Campbell, Complete Casting Handbook: Metal Casting Processes, Metallurgy,Techniques and Design, 2nd edition, Butterworth-Heinemann, 2015.
  9. R. Gopalan, N.K. Prabhu, Oxide bifilms in aluminium alloy castings–a review,Mater. Sci. Technol. 27 (12) (2011) 1757–1769.
  10. J. Campbell, The consolidation of metals: the origin of bifilms, J. Mater. Sci. 51 (1)(2016) 96–106.
  11. R. Raiszadeh, W.D. Griffiths, A method to study the history of a double oxide filmdefect in liquid aluminum alloys, Metal. Mater. Trans. B 37 (6) (2006) 865–871.
  12. X. Cao, J. Campbell, The nucleation of Fe-rich phases on oxide films in Al-11.5 Si0.4 Mg cast alloys, Metal. Mater. Trans. A 34 (7) (2003) 1409–1420.
  13. A. Modaresi, A. Safikhani, A.M.S. Noohi, N. Hamidnezhad, S.M. Maki, Gatingsystem design and simulation of gray iron casting to eliminate oxide layers causedby turbulence, Int. J. Metalcast. 11 (2) (2017) 328–339.
  14. F.N. Bakhtiarani, R. Raiszadeh, Healing of double-oxide film defects in commercialpurity aluminum melt, Metal. Mater. Trans. B 42 (2) (2011) 331–340.
  15. F.H. Basuny, M. Ghazy, A.R.Y. Kandeil, M.A. El-Sayed, Effect of casting conditionson the fracture strength of Al-5 Mg alloy castings, Adv. Mater. Sci. Eng. 2016(2016).
  16. J. Campbell, Castings, 2nd edition, Butterworth-Heinemann, 2003.
  17. X. Dai, X. Yang, J. Campbell, J. Wood, Influence of oxide film defects generated infilling on mechanical strength of aluminium alloy castings, Mater. Sci. Technol. 20(4) (2004) 505–513.
  18. M. Divandari, J. Campbell, Mechanisms of Bubble Damage in Castings. Universityof Birmingham. PhD Dissertation, The School of Metallurgy and Materials, 2001.
  19. J. Mi, R.A. Harding, J. Campbell, Effects of the entrained surface film on the reliability of castings, Metal. Mater. Trans. A 35 (9) (2004) 2893–2902.
  20. B. Sirrell, J. Campbell, Mechanism of filtration in reduction of casting defects due tosurface turbulence during mold filling (97-11), Trans. Am. Foundrymen’s Soc. 105(1997) 645–654.
  21. X.Y. Zhao, Z.L. Ning, F.Y. Cao, S.G. Liu, Y.J. Huang, J.S. Liu, J.F. Sun, Effect ofdouble oxide film defects on mechanical properties of As-cast C95800 alloy, ActaMetallurgica Sinica (Eng. Lett.) 30 (6) (2017) 541–549.
  22. C. Nyahumwa, N.R. Green, J. Campbell, Effect of mold-filling turbulence on fatigueproperties of cast aluminum alloys (98-58), Trans. Am. Foundrymen’s Soc. 106(1998) 215–224.
  23. N.R. Green, J. Campbell, Influence of oxide film filling defects on the strength of Al7Si-Mg alloy castings (94-114), Trans. Am. Foundrymen’s Soc. 102 (1994) 341–348.
  24. S.H. Majidi, J. Griffin, C. Beckermann, Simulation of air entrainment during moldfilling: comparison with water modeling experiments, Metal. Mater. Trans. B 49 (5)(2018) 2599–2610.
  25. X. Cao, J. Campbell, Oxide inclusion defects in Al-Si-Mg cast alloys, Can. Metall. Q.44 (4) (2005) 435–448.
  26. K. Bangyikhan, Effects of Oxide Film, Fe-Rich Phase, Porosity and Their Interactionson Tensile Properties of Cast Al-Si-Mg Alloys. PhD Thesis, University ofBirmingham. School of Metallurgy and Materials, 2005.
  27. R. Raiszadeh, W.D. Griffiths, A semi-empirical mathematical model to estimate theduration of the atmosphere within a double oxide film defect in pure aluminumalloy, Metal. Mater. Trans. B 39 (2) (2008) 298–303.
  28. G.E. Bozchaloei, N. Varahram, P. Davami, S.K. Kim, Effect of oxide bifilms on themechanical properties of cast Al–7Si–0.3 Mg alloy and the roll of runner height afterfilter on their formation, Mater. Sci. Eng.: A 548 (2012) 99–105.
  29. J. Campbell, Invisible macrodefects in castings, Le J. de Physique IV 3 (C7) (1993)C7–861.
  30. S.M.A. Boutorabi, J. Campbell, J.J. Runyoro, Critical gate velocity for film-formingcasting alloys; a basis for process specifications, Trans. Am. Foundrymen’s Soc. 100(1992) 225–234.
  31. J. Brown, Foseco non-Ferrous Foundryman’s Handbook, 1st edition, ButterworthHeinemann, 1999.
  32. T.R. Rao, Metal Casting: principles and Practice. New Age International, 1st edition,(1996).
  33. X. Yang, T. Din, J. Campbell, Liquid metal flow in moulds with off-set sprue, Int. J.Cast Met. Res. 11 (1) (1998) 1–12.
  34. A.K. Biń, Gas entrainment by plunging liquid jets, Chem. Eng. Sci. 48 (21) (1993)3585–3630.
  35. C. Beckermann, Water modeling of steel flow, air entrainment and filtration,September, SFSA T&O Conference (1992).
  36. R.W. Ruddle, The running and gating of Sand casting, Inst. Met. Monogr. Rep. Ser.(1956) 19.
  37. R.E. Swift, J.H. Jackson, L.W. Eastwood, A study of principles of gating, AFS Trans.57 (1949) 76–88.
  38. K.H. Renukananda, B. Ravi, Multi-gate systems in casting process: comparativestudy of liquid metal and water flow, Mater. Manuf. Processes 31 (8) (2016)1091–1101.
  39. R. Cuesta, J.A. Maroto, D. Morinigo, I. De Castro, D. Mozo, Water analogue experiments as an accurate simulation method of the filling of aluminum castings,Trans.-Am. Foundrymens Soc. 114 (2006) 137–150.
  40. S.L. Nimbulkar, R.S. Dalu, Design optimization of gating and feeding systemthrough simulation technique for sand casting of wear plate, Perspect. Sci. 8 (2016)39–42.
  41. H. Iqbal, A.K. Sheikh, A. Al-Yousef, M. Younas, Mold design optimization for sandcasting of complex geometries using advance simulation tools, Mater. Manuf.Processes 27 (7) (2012) 775–785.
  42. Z. Sun, H. Hu, X. Chen, Numerical optimization of gating system parameters for amagnesium alloy casting with multiple performance characteristics, J. Mater.Process. Technol. 199 (1-3) (2008) 256–264.
  43. E. Rabinovich, Mécanique Des Fluides, Comptes Rendus (Doklady) de L’AcadémieDes Sciences de L’URSS Vol. 54 Édition de l’Académie des sciences de l’URSS, 1946No. 5, p. 391.
  44. M.B.N. Shaikh, S. Ahmad, A. Khan, M. Ali, August. Optimization of multi-gatesystems in casting process: experimental and simulation studies, IOP ConferenceSeries: MaTerials Science and Engineering IOP Publishing 404 (2018) No 1.012040.
  45. W. Sun, C.E. Bates, Visualizing defect formation in gray iron castings using real timeX-rays, Trans. Am. Foundry Soc. Vol. 111 (2003) 859–867.
  46. F.R. Juretzko, D.M. Stefanescu, Comparison of mold filling simulation with highspeed video recording of real-time mold filling, AFS Trans. 113 (2005) 1–11.
  47. D. Kothe, D. Juric, K. Lam, B. Lally, Numerical recipes for mold filling simulation(April), Proceedings of the Eighth International Conference on Modeling of Casting,Welding, and Advanced Solidification Processes (1998).
  48. P. Cleary, J. Ha, V. Alguine, T. Nguyen, Flow modelling in casting processes, Appl. Math. Modell. 26 (2) (2002) 171–190.
  49. J. Jezierski, R. Dojka, K. Janerka, Optimizing the gating system for steel castings,Metals 8 (4) (2018) 266.
  50. C.E. Esparza, M.P. Guerrero-Mata, R.Z. Ríos-Mercado, Optimal design of gatingsystems by gradient search methods, Comput. Mater. Sci 36 (4) (2006) 457–467.
  51. J. Kor, X. Chen, H. Hu, Multi-objective optimal gating and riser design for metalcasting, July, Control Applications, (CCA) Intelligent Control, IEEE, 2009, pp.428–433.
  52. S.R. Sama, J. Wang, G. Manogharan, Non-conventional mold design for metalcasting using 3D sand-printing, J. Manuf. Processes. (2018).
  53. F.Y. Hsu, M.R. Jolly, J. Campbell, A multiple-gate runner system for gravity casting,J. Mater. Process. Technol. 209 (17) (2009) 5736–5750.
  54. R. Ahmad, N. Talib, Experimental study of vortex flow induced by a vortex well insand casting, Revue de Métallurgie–Int. J. Metal. 108 (3) (2011) 129–139.
  55. H. Shangguan, J. Kang, C. Deng, Y. Hu, T. Huang, 3D-printed shell-truss sand moldfor aluminum castings, J. Mater. Process. Technol. 250 (2017) 247–253.
  56. M. Tiryakioglu, D.R. Askeland, C.W. Ramsay, Fluidity of 319 and A356: an experimental design approach, Trans.-Am. Foundrymens Soc. (1995) 17–26.
  57. W.S. Hwang, R.A. Stoehr, Fluid flow modeling for computer-aided design of castings, JOM 35 (10) (1983) 22–29.
  58. S.E. Haaland, Simple and explicit formulas for the friction factor in turbulent pipeflow, J. Fluids Eng. 105 (1) (1983) 89–90.
  59. D. Vaghasia, Gating System Design Optimization for Sand Casting. Indian Instituteof Technology Bombay. M. Tech Dissertation. Manufacturing Engineering, (2009).
  60. American Society of Mechanical Engineers. Standards Committee B46.Classification, & Designation of Surface Qualities. (2003). Surface texture: Surfaceroughness, waviness and lay. Amer Society of Mechanical.
  61. N. Wukovich, G. Metevelis, ). Gating: the Foundryman’s dilemma or fifty years ofdata and still asking how? 93Rd AFS Casting Congress, (1989).
  62. P. Muenprasertdee, Solidification Modeling of Iron Castings Using SOLIDCast. WestVirginia University. MS Thesis, Industrial and Management Systems Engineering,2007.
  63. D. Snelling, H. Blount, C. Forman, K. Ramsburg, A. Wentzel, C. Williams,A. Druschitz, The effects of 3D printed molds on metal castings, In Proceedings ofthe Solid Freeform Fabrication Symposium, (2013), pp. 827–845.
  64. American Society of Mechanical Engineers. Standards Committee E28. MechanicalTesting. (2004). Standard Test Methods for Bend Testing of Material for DuctilityE290-14. Amer Society for Mechanical.
  65. B. Sirrell, M. Holliday, J. Campbell, Benchmark testing the flow and solidificationmodeling of AI castings, Jom 48 (3) (1996) 20–23.
  66. M. Masoumi, H. Hu, J. Hedjazi, M. Boutorabi, Effect of gating design on moldfilling, Trans. Am. Foundry Soc. 113 (113) (2005) 185–196.
  67. P.C. Belding, The Control of non-Metallic Inclusions in Cast Steel. Organ StateUniversity. MS Thesis, Metallurgical Engineering, 1971.
  68. W.S. Rasband, Image J. US, National Institutes of Health, Bethesda, MD, USA, 1997.
  69. J.A. Griffin, C.E. Bates, Ladle Treating, Pouring, and Gating for the Production ofClean Steel Castings, Technical Steering Committee, Steel Founders’ Society ofAmerica, 1991.
  70. L. Wang, C. Beckermann, Prediction of reoxidation inclusion composition in castingof steel, Metal. Mater. Trans. B 37 (4) (2006) 571–588.
  71. X. Dai, X. Yang, J. Campbell, J. Wood, Effects of runner system design on the mechanical strength of Al–7Si–Mg alloy castings, Mater. Sci. Eng.: A 354 (1-2) (2003)315–325.
  72. R. Monroe, Porosity in castings, AFS Trans. 113 (2005) 519–546.
  73. R.B. Tuttle, M. Masoumi, H. Hu, J. Hedjazi, M. Boutorabi, Macroinclusion sourceswithin the steel casting process, American Foundry Society Proceedings, (2010).
  74. M. Harris, V. Richards, R.J. O’Malley, S.N. Lekakh, Chicago, ILEvolution of NonMetallic Inclusions in Foundry Steel Casting Processes. Proceedings of the 69thAnnual Technical and Operating Conference, Steel Founders’ Society ofAmerica2015, December, Evolution of Non-Metallic Inclusions in Foundry SteelCasting Processes. Proceedings of the 69th Annual Technical and OperatingConference, Steel Founders’ Society of America (2015).
  75. K.D. Carlson, C. Beckermann, Modeling of reoxidation inclusion formation duringfilling of steel castings, Proceedings of the 58th Annual Technical and OperatingConference, Steel Founders’ Society of America. Chicago, IL. Paper 4.6, (2004).
  76. A.S. Murthy, S.N. Lekakh, D.C. Van Aken, Role of niobium and effect of heattreatments on strength and toughness of modified 17-4 PH stainless steel,Proceedings of the 63rd Annual Technical and Operating Conference, SteelFounders’ Society of America. Chicago, IL. Paper 3.4, (2010).
  77. ASK Chemicals, Udicell And Exactflo Filters, Accessible on: Available: http://www.ask-chemicals.com/fileadmin/user_upload/Download_page/foundry_products_brochures/EN/Udicell_Exactflo_Overview_EN.pdf.
  78. P.F. Wieser, Filtration of Irons and Steels. Foundry Processes – Their Chemistry andPhysics, Springer, Boston, MA, 1988, pp. 495–512.
  79. American Society of Mechanical Engineers. Standards Committee E04.Metallography. (2015). Standard practice for microetching metals and alloys E407-07. Amer Society for Mechanical.
  80. M. Di Sabatino, Fluidity of Aluminium Foundry Alloys. Norwegian University ofScience and Technology. PhD Thesis, Materials Science and Engineering, 2005.
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