Manufacturing of cellular A2011 alloy from semi-solid state

• Autorzy: Robert M. H. , Delbin D.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The work presents a new method to produce cellular metallic material by pressing the alloy in the thixotropic semi-solid state into a layer of space holder particles, which are removed from the product after the forming operation. Design/methodology/approach: It is investigated the influence of the thixoforming temperature and the size of space holder particles, in the ability of penetration of the slurry in the porous preform as well as the structure of the obtained porous material (general aspect, quantitative and qualitative characterization of porosity microstructure of cells walls and density of the product). Findings: Cylindrical samples presenting three different ranges of porosity were produced. The cellular material obtained contains open porosity, being characterized as sponge. Products were analyzed by tomography and metallographic techniques. Results show that the proposed process is able to produce acceptable porous material, in a simple and low cost technique. The quality of the product depends rather on the processing temperature than on the size of space holder particles. Low liquid fraction in the thixotropic slurry can lead to incomplete infiltration and deformation of the preform. In the analyzed conditions influence of the size of space holder particles could be observed neither in the processing ability nor in the quality of the product. Density of produced porous material increases as processing temperature increases, due to the increase of cells walls thickness. Research limitations/implications: The investigated process is suitable only for alloys with a significant solidification range. Practical implications: The new method to produce cellular metals can represent energy savings and is highly operational when compared to conventional methods based on liquid infiltration, since lower temperatures are involved and no need of liquid handling is required. Originality/value: the process proposed is a new one; no techniques based on thixoforming of the alloy into porous preforms are known so far.

Słowa kluczowe

EN

metallic alloys; cellular material; porous material; metallic foams; metallic sponges; thixoforming

PL

stopy metaliczne; materiał komórkowy; materiał porowaty; pianki metalowe; gąbczaste materiały metaliczne; formowanie tiksotropowe

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 24, nr 1
• Strony: 115--122
• Opis fizyczny: Bibliogr. 10 poz., fot., rys., tab.

Twórcy

autor

Robert M. H.

autor

Delbin D.

• Faculty of Mechanical Engineering, State University of Campinas, SP, Brazil,

Bibliografia

• [1] J. Banhart, Al foams: on the road for real application, MRS Bulletin (2003) 290-293.
• [2] D.Z. Sun, F. Andrieux, C. Harbeling, Characterization and simulation of mechanical behavior of Al foams, Met Foam 2003, Verlag MIT Publising, 2003.
• [3] C. Harbeling, The range of applications of structural foams based on cellular metals and alternative polymer solutions. Handbook of Cellular Metals, Wiley VCH, 2002.
• [4] G. Rausch, J. Banhart, Making cellular metals from metals other than Aluminium, Handbook of Cellular Metals, Wiley VCH, Weinheim, 2002.
• [5] J. Banhart, Manufacturing routes for metallic foams, JOM 2000.
• [6] C. San Marchi, A. Mortensen, Infiltration and replication process for producing metal sponges, Handbook of Cellular Metals, Wiley VCH, Weinheim, 2002.
• [7] A.E. Markaki, T.W. Clyne, The effect of cell wall microstructure on the deformation and fracture of aluminium based foams. Acta Materiallia 49 (2001) 1677-1686.
• [8] M.H. Robert, Partial melting as an efficient method to produce rheocast alloy slurries, Transactions of the Japan Foundrymen's Society 12 (1993) 45-51.
• [9] M.M. Rovira, M.H. Robert, Effect of the thixoforging operation on the microstructure of AA2011 alloy Proceedings of the 10th International Scientific Conference Achievements in Mechanical and Materials Engineering, Zakopane, 2001, 357-360.
• [10] E.J. Zoqui, M.H. Robert, Structural modifications in rheocast Al-Cu alloys by heat treatment and implications on mechanical properties, Journal of Materials Processing Technology 78 (1998) 198-203.