Novel technologies for the lost foam casting process

doi:10.1007/s11465-018-0473-2

Front. Mech. Eng.

2018, Vol. 13

Issue (1) : 37-47 https://doi.org/10.1007/s11465-018-0473-2

REVIEW ARTICLE

Novel technologies for the lost foam casting process

Wenming JIANG, Zitian FAN(

)

State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China

Download: PDF(916 KB) HTML
Export: BibTeX | EndNote | Reference Manager | ProCite | RefWorks

Abstract

Lost foam casting (LFC) is a green precision casting process categorized as a near net forming technology. Yet, despite its popularity, it still suffers from some technological problems, such as poor filling ability of the castings, coarse and non-dense microstructure, low mechanical properties for the Al and Mg LFC processes, and defective carburization for the low carbon steel LFC process. These drawbacks restrict the development and widespread application of the LFC process. To solve these problems, the present study developed several novel LFC technologies, namely, LFC technologies under vacuum and low pressure, vibration solidification, and pressure solidification conditions; expendable shell casting techno- logy; and preparation technology of bimetallic castings based on the LFC process. The results showed that the LFC under vacuum and low pressure evidently improved the filling ability and solved the oxidization problem of the alloys, which is suitable for producing complex and thin-wall castings. The vibration and pressure solidifications increased the compactness of the castings and refined the microstructure, significantly improving the mechanical properties of the castings. The expendable shell casting technology could solve the pore, carburization, and inclusion defects of the traditional LFC method, obtaining castings with acceptable surface quality. Moreover, the Al/Mg and Al/Al bimetallic castings with acceptable metallurgical bonding were successfully fabricated using the LFC process. These proposed novel LFC technologies can solve the current technological issues and promote the technological progress of the LFC process.

Keywords LFC under vacuum and low pressure vibration solidification pressure solidification expendable shell casting bimetallic castings

Corresponding Author(s): Zitian FAN

Just Accepted Date: 13 September 2017 Online First Date: 30 October 2017 Issue Date: 23 January 2018

Cite this article:

Wenming JIANG,Zitian FAN. Novel technologies for the lost foam casting process[J]. Front. Mech. Eng., 2018, 13(1): 37-47.

URL:

https://academic.hep.com.cn/fme/EN/10.1007/s11465-018-0473-2
https://academic.hep.com.cn/fme/EN/Y2018/V13/I1/37

Fig.1 Schematic of the LFC under low pressure and vacuum

Fig.2 Comparison of Mg alloy motor castings obtained using different casting processes. (a) LFC under low pressure and vacuum; (b) LFC under gravity

Fig.3 Schematic of LFC under vibration solidification

Fig.4 Schematic of dendrite fragmentation mechanism. (a) Primary crystal; (b) dendritic growth; (c) dendrite fragmentation; (d) round grains

Fig.5 Optical microstructures of the LFC AZ91D alloys obtained using different amplitudes. (a) Without vibration; (b) 50 Hz, 0.11 mm vibration; (c) 50 Hz, 0.23 mm vibration; (d) 50 Hz, 0.34 mm vibration

Fig.6 Optical microstructures of the LFC ZL101 alloys obtained using different frequencies. (a) Without vibration; (b) 20 Hz, 0.23 mm vibration; (c) 40 Hz, 0.23 mm vibration; (d) 60 Hz, 0.23 mm vibration

Fig.7 Morphologies of the graphite of the QT500-7 ductile iron obtained using different frequencies. (a) Without vibration; (b) 50 Hz

Fig.8 Matrix microstructures of the QT500-7 ductile iron obtained using different frequencies. (a) Without vibration; (b) 50 Hz

Fig.9 Production line of the LFC under pressure solidification for Mercury Castings Company

Fig.10 Schematic of LFC under pressure solidification

Fig.11 Schematic of solidification area structure

Fig.12 Effect of pressure solidification on the pinhole defect of the A356 Al alloy LFC castings. (a) 0.0 MPa; (b) 0.2 MPa; (c) 0.4 MPa; (d) 0.6 MPa

Fig.13 Effect of pressure solidification on the shrinkage defect of the AZ91D Mg alloy LFC castings. (a) 0 MPa; (b) 0.6 MPa

Fig.14 Schematic of the expendable shell casting process under vacuum and low pressure

Fig.15 Simulation of the filling process of the expendable shell casting technology under vacuum and low pressure

Fig.16 Prediction of shrinkage defects

Fig.17 Schematic of defect formation during the LFC process

Fig.18 Intake manifold castings produced using different casting processes. (a) Foam pattern; (b) ceramic shell; (c) casting obtained with the novel casting process; (d) cross-section corresponding to (c); (e)casting obtained with the LFC process; (f) cross-section corresponding to (e)

Fig.19 Schematic of the preparation technology of bimetallic castings based on the LFC method

Fig.20 Formation mechanism of the interface layer of the Al/Mg bimetallic composites obtained by the LFC method. (a) Before the pouring; (b) foam decomposed; (c) molten pool generated; (d) mold filling completed; (e) elements diffused; (f) interface layer formed

Fig.21 Micrographs and phase compositions of the reaction layer of the Al/Mg bimetallic castings by the LFC method. (a) Optical micrograph; (b) scanning electron microscope (SEM) micrograph; (c) EDS analysis; (d) XRD pattern

Fig.22 Micrographs of the reaction layer of the Al/Al bimetallic castings by the LFC method. (a) Optical micrograph; (b–d) SEM micrographs

1	Huang N, Ye S, Fan Z. Principle and Control of Lost Foam Casting. Wuhan: Huazhong University of Science and Technology Press, 2004
2	Huang T, Huang N, Lv Z. Lost Foam Casting Technology. Beijing: Mechanical Industry Press, 2004
3	Charchi A, Rezaei M, Hossainpour S, et al.Numerical simulation of heat transfer and fluid flow of molten metal in MMA–St copolymer lost foam casting process. Journal of Materials Processing Technology, 2010, 210(14): 2071–2080 doi:10.1016/j.jmatprotec.2010.07.028
4	Liu Z, Hu J, Wang Q, et al.Evaluation of the effect of vacuum on mold filling in the magnesium EPC process. Journal of Materials Processing Technology, 2002, 120(1–3): 94–100 https://doi.org/10.1016/S0924-0136(01)01085-8
5	Geffroy P, Lakehal M, Goñi J, et al.Thermal and mechanical behaviour of grey cast iron and ductile iron castings using magnetic molding and lost foam processes. Journal of Materials Processing Technology, 2009, 209(8): 4103–4111 https://doi.org/10.1016/j.jmatprotec.2008.10.002
6	Shayegh J, Hossainpour S, Rezaei M, et al.Developing a new 2D model for heat transfer and foam degradation in EPS lost foam casting (LFC) process. International Communications in Heat and Mass Transfer, 2010, 37(9): 1396–1402 https://doi.org/10.1016/j.icheatmasstransfer.2010.07.015
7	Liu X, Bhavnani S H, Overfelt R A. Simulation of EPS foam decomposition in the lost foam casting process. Journal of Materials Processing Technology, 2007, 182(1–3): 333–342 https://doi.org/10.1016/j.jmatprotec.2006.08.023
8	Sands M, Shivkumar S. EPS bead fusion effects on fold defect formation in lost foam casting of aluminum alloys. Journal of Materials Science, 2006, 41(8): 2373–2379 https://doi.org/10.1007/s10853-006-7077-7
9	Shin S R, Lee Z H, Cho G S, et al.Hydrogen gas pick-up mechanism of Al-alloy melt during lost foam casting. Journal of Materials Science, 2004, 39(5): 1563–1569 https://doi.org/10.1023/B:JMSC.0000016152.96919.6c
10	Fan Z, Jiang W, Liu F, et al.. Status quo and development trend of lost foam casting technology. China Foundry, 2014, 11(4): 296–307
11	Fan Z, Dong X, Huang N, et al.China Patent, ZL02115638.7, 2002-12-04 (in Chinese)
12	Fan Z, Ji S. Low pressure lost foam process for casting magnesium alloys. Materials Science and Technology, 2005, 21(6): 727–734 https://doi.org/10.1179/174328405X43199
13	Li J, Zhao Z, Fan Z, et al.. Study on typical hole defects in AZ91D magnesium alloy prepared by low pressure lost foam casting. China Foundry, 2013, 10(4): 232–236 https://doi.org/10.3969/j.issn.1672-6421.2013.04.006
14	Zhao Z. Study on microstructures and mechanical properties of aluminum (magnesium) alloy under vibration and pressure in lost foam casting process. Dissertation for the Doctoral Degree. Wuhan: Huazhong University of Science and Technology, 2010
15	Zhao Z, Fan Z, Jiang W, et al.Microstructural evolution of Mg9AlZnY alloy with vibration in lost foam casting during semi-solid isothermal heat treatment. Transactions of Nonferrous Metals Society of China, 2010, 20(Suppl3): s768–s773 https://doi.org/10.1016/S1003-6326(10)60579-1
16	Zhao Z, Fan Z, Dong X, et al.. Influence of mechanical vibration on the solidification of a lost foam cast 356 alloy. China Foundry, 2010, 7(1): 24–29
17	Fan Z, Li J, Tian X, et al.China Patent, CN200710168429.1, 2008-05-21
18	Jiang W, Chen X, Wang B, et al. Effects of vibration frequency on microstructure, mechanical properties and fracture behavior of A356 aluminum alloy obtained by expendable pattern shell casting. International Journal of Advanced Manufacturing Technology, 2016, 83(1–4): 167–175 https://doi.org/10.1007/s00170-015-7586-0
19	Xiao B. Characteristics of microstructure and properties of cast iron produced by lost foam casting with vibration. Dissertation for the Doctoral Degree. Wuhan: Huazhong University of Science and Technology, 2013 https://doi.org/10.7666/d.D608931
20	Xiao B, Fan Z, Jiang W, et al.Microstructure and mechanical properties of ductile cast iron in lost foam casting with vibration. Journal of Iron and Steel Research International, 2014, 21(11): 1049–1054 https://doi.org/10.1016/S1006-706X(14)60182-5
21	Zou W, Zhang Z, Yang H, et al.Effect of vibration frequency on microstructure and performance of high chromium cast iron prepared by lost foam casting. China Foundry, 2016, 13(4): 248–255 https://doi.org/10.1007/s41230-016-6037-3
22	Fan Z, Zhao Z, Tang B, et al.China Patent, CN200810197390.0, 2009-03-25
23	Zhao Z, Fan Z, Tang B, et al.Influence of pressure solidification on AZ91D magnesium alloy feeding in lost foam casting process. International Journal of Cast Metals Research, 2011, 24(1): 13–21 https://doi.org/10.1179/136404610X12816241546537
24	Jiang W, Fan Z, Liu D, et al.Effects of process parameters on internal quality of castings during novel casting. Materials and Manufacturing Processes, 2012, 28(1): 48–55 https://doi.org/10.1080/10426914.2012.681414
25	Ridder S D, Kou S, Mehrabian R. Effect of fluid flow on macrosegregation in axi-symmetric ingots. Metallurgical Transactions B, 1981, 12(3): 435–447
26	Ashton M C, Sharman S G, Brookes A J. The replicast CS (ceramic s hell) process. Materials & Design, 1984, 5(2): 66–75 https://doi.org/10.1016/0261-3069(84)90159-6
27	Jiang W, Fan Z, Liao D, et al.A new shell casting process based on expendable pattern with vacuum and low-pressure casting for aluminum and magnesium alloys. International Journal of Advanced Manufacturing Technology, 2010, 51(1–4): 25–34 https://doi.org/10.1007/s00170-010-2596-4
28	Jiang W, Fan Z, Chen X, et al.Combined effects of mechanical vibration and wall thickness on microstructure and mechanical properties of A356 aluminum alloy produced by expendable pattern shell casting. Materials Science and Engineering A, 2014, 619(12): 228–237 https://doi.org/10.1016/j.msea.2014.09.102
29	Liao D, Fan Z, Jiang W, et al.Study on the surface roughness of ceramic shells and castings in the ceramic shell casting process based on expandable pattern. Journal of Materials Processing Technology, 2011, 211(9): 1465–1470 https://doi.org/10.1016/j.jmatprotec.2011.03.021
30	Jiang W, Fan Z, Liu D, et al.Influence of process parameters on filling ability of A356 aluminium alloy in expendable pattern shell casting with vacuum and low pressure. International Journal of Cast Metals Research, 2012, 25(1): 47–52 https://doi.org/10.1179/1743133611Y.0000000014
31	Jiang W, Fan Z, Liu D, et al.Influence of gas flowrate on filling ability and internal quality of A356 aluminum alloy castings fabricated using the expendable pattern shell casting with vacuum and low pressure. International Journal of Advanced Manufacturing Technology, 2013, 67(9–12): 2459–2468 https://doi.org/10.1007/s00170-012-4663-5
32	Jiang W, Fan Z, Liao D, et al.Investigation of microstructures and mechanical properties of A356 aluminum alloy produced by expendable pattern shell casting process with vacuum and low pressure. Materials & Design, 2011, 32(2): 926–934 https://doi.org/10.1016/j.matdes.2010.08.015
33	Emami S M, Divandari M, Hajjari E, et al.Comparison between conventional and lost foam compound casting of Al/Mg light metals. International Journal of Cast Metals Research, 2013, 26(1): 43–50 https://doi.org/10.1179/1743133612Y.0000000037
34	Guler K A, Kisasoz A, Karaaslan A. Investigation of lost foam casted aluminum bimetal microstructures. Materials Testing, 2014, 56(9): 737–740 https://doi.org/10.3139/120.110625
35	Guler K A, Kisasoz A, Karaaslan A. Fabrication of Al/Mg bimetal compound casting by lost foam technique and liquid-solid process. Materials Testing, 2014, 56(9): 700–702 https://doi.org/10.3139/120.110624
36	Divandari M, Vahid Golpayegani A R. Study of Al/Cu rich phases formed in A356 alloy by inserting Cu wire in pattern in LFC process. Materials & Design, 2009, 30(8): 3279–3285 https://doi.org/10.1016/j.matdes.2009.01.008
37	Mehdi Hejazi M, Divandari M, Taghaddos E. Effect of copper insert on the microstructure of gray iron produced via lost foam casting. Materials & Design, 2009, 30(4): 1085–1092 https://doi.org/10.1016/j.matdes.2008.06.032
38	Choe K H, Park K S, Kang B H, et al.. Study of the interface between steel insert and aluminum casting in EFC. Journal of Materials Science and Technology, 2008, 24(1): 60–64
39	Xiao X, Ye S, Yin W, et al.HCWCI/carbon steel bimetal liner by liquid-liquid compound lost foam casting. Journal of Iron and Steel Research International, 2012, 19(10): 13–19 https://doi.org/10.1016/S1006-706X(12)60145-9
40	Xiao X, Ye S, Yin W, et al.. High Cr white cast iron/carbon steel bimetal liner by lost foam casting with liquid-liquid composite process. China Foundry, 2012, 9(2): 136–142
41	Jiang W, Li G, Fan Z, et al.Investigation on the interface characteristics of Al/Mg bimetallic castings processed by lost foam casting. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 2016, 47(5): 2462–2470 https://doi.org/10.1007/s11661-016-3395-9
42	Jiang W, Fan Z, Li G, et al.Effects of melt-to-solid insert volume ratio on the microstructures and mechanical properties of Al/Mg bimetallic castings produced by lost foam casting. Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 2016, 47(12): 6487–6497 https://doi.org/10.1007/s11661-016-3788-9
43	Li G, Jiang W, Fan Z, et al.Effects of pouring temperature on microstructure, mechanical properties, and fracture behavior of Al/Mg bimetallic composites produced by lost foam casting process. International Journal of Advanced Manufacturing Technology, 2017, 91(1–4): 1355–1368 https://doi.org/10.1007/s00170-016-9810-y

Viewed

Full text

Abstract

Cited

Shared

Discussed