Effect of stirring velocity in micro fused-casting for metal on microstructure and mechanical properties of A356 aluminum alloy slurry

Abstract

A novel micro fused-casting for metal (MFCM) process for producing A356 aluminum alloy slurry was proposed. MFCM means that the refined metal slurry is pressed out from the outlet of bottom of crucible to the horizontal movable plate. With the aid of 3D manufacturing software, the melt is solidified and formed layer by layer. The stirring could keep the ingredients and the heat diffusion of metal slurry uniform in the crucible due to the shear force breaking down the dendrite arms. The solidus and liquidus temperatures of A356 alloy were 559.2 and 626.3 °C, respectively, which were measured by differential scanning calorimetry (DSC). Effect of different stirring velocities of MFCM on the microstructure and mechanical properties of A356 slurry was investigated with the pouring temperature controlled at 620 °C. The microstructure and mechanical performance were the best when the stirring velocity was 1 200 r/min in MFCM. The microstructures of the A356 aluminum alloy slurry were mainly composed of fine spherical or rose grains. The average roundness and average grain size reached 2.2 and 41 μm and the tensile strength of A356 alloy slurry reached 207.8 MPa, while the average vickers hardness was 81.1 HV.

Keywords

micro fused-casting / stirring velocity / microstructure / mechanical property

References

[1] Sercombe T B, Schaffer G B. Rapid Manufacturing of Aluminum Components[J]. Sci., 2003, 301(5637): 1225-1227.

[2] Seno T, Ohtake Y, Kikuchi Y, et al. 3D Scanning Based Mold Correction for Planar and Cylindrical Parts in Aluminum Die Casting[J]. Journal of Computational Design and Engineering, 2015, 2(2): 96-104.

[3] Crump S S. Fast, Precise, Safe Prototypes with FDM[J]. Intelligent Design and Manufacturing for Prototyping, PED, 1991, 50: 53-60.

[4] L XQ, L ZY, C GN, et al. Effect of Substrate Movement Speed by Synchronous Rolling-Casting Freeform Manufacturing for Metal on Microstructure and Mechanical Property of ZLl04 Aluminum Alloy Slurry[J]. J. Wuhan Univer. Technol-Mater. Sci.Ed., 2015, 30(5): 1056-1060.

[5] Orme M. A Novel Technique of Rapid Solidification Net-Form Materials Synthesis[J]. Journal of Materials Engineering and Performance, 1993, 2(3): 399-405.

[6] Crump S S. Rapid Prototyping Using FDM[J]. Modern Casting, 1992, 82(4): 36-38.

[7] Thompson S M, Bian L, Shamsaei N, et al. An Overview of Direct Laser Deposition for Additive Manufacturing; Part I: Transport Phenomena, Modeling and Diagnostics[J]. Additive Manufacturing, 2015, 8: 36-62.

[8] Liska R, Schuster M I R, et al. Photopolymers for Rapid Prototyping[J]. Journal of Coatings Technology and Research, 2007, 4(4): 505-510.

[9] Kunce I, Polanski M, Bystrzycki J. Microstructure and Hydrogen Storage Properties of a TiZrNbMoV High Entropy Alloy Synthesized Using Laser Engineered Net Shaping (LENS)[J]. International Journal of Hydrogen Energy, 2014, 39(18): 9904-9910.

[10] Durejko T, Zietala M l M, et al. Structure and Properties of the Fe 3 Al-Type Intermetallic Alloy Fabricated by Laser Engineered Net Shaping (LENS)[J]. Materials Science and Engineering: A, 2016, 650: 374-381.

[11] Eskin D G, Katgerman L. Mechanical Properties in the Semi-Solid State and Hot Tearing of Aluminium Alloys[J]. Progress in Materials Science, 2004, 49(5): 629-711.

[12] Chen Z, Mao W. Rheo-diecasting Performance of the Semi-Solid Slurry Prepared by Serpentine Channel Pouring and After Soaked[J]. Materials Science and Technology, 2012, 2: 14.

[13] Ceschini L, Morri A, Sambogna G. The Effect of Hot Isostatic Pressing on the Fatigue Behaviour of Sand-Cast A356-T6 and A204-T6 Aluminum Alloys[J]. Journal of Materials Processing Technology, 2008, 204(1-3): 231-238.

[14] Huang X S, He L J, Mi G B, et al. Characteristics of Defect Bands and Their Formation Mechanisms in A356 Wheel Fabricated by Horizontal Squeeze Casting[J]. Materials Science and Technology, 2015, 31(4): 400-408.

[15] Williams J D, Deckard C R. Advances in Modeling the Effects of Selected Parameters on the SLS Process[J]. Rapid Prototyping Journal, 1998, 4(2): 90-100.

[16] Flemings M C. Behavior of Metal Alloys in the Semisolid State[J]. Metallurgical Transactions B, 1991, 22(3): 269-293.

[17] Esgandari B A, Nami B, Shahmiri M, et al. Effect of Mg and Semi Solid Processing on Microstructure and Impression Creep Properties of A356 Alloy[J]. Transactions of Nonferrous Metals Society of China, 2013, 9: 2518-2523.

[18] Shamsaei N, Yadollahi A, Bian L, et al. An Overview of Direct Laser Deposition for Additive Manufacturing; Part II: Mechanical Behavior, Process Parameter Optimization and Control[J]. Additive Manufacturing, 2015, 8: 12-35.