Microstructure and Properties of Vacuum Cast Sc-Containing Be–Al Alloys
- 30 Downloads
The cross-sectional microstructure and mechanical properties of vacuum suction cast beryllium–aluminum (Be–Al) alloy rods with different additions of scandium (Sc) were firstly investigated. The vacuum suction casting process was numerically simulated with the filling time of 0.1 s and solidification rate of 870 °C/s roughly obtained. The sub-rapid solidification process rendered no amorphous phases but three kinds of distinguished microstructures, of which the crystallization type and grain size of Be in the central part varied with increasing additions of Sc. The Al3Sc phase could only exist with a high content of Sc. Rapid solidification hindered macro-segregation and resulted in secondary phases with homogeneous compositions. The 1.0 wt% addition of Sc caused microscopic shrinkage porosities in the center of alloy rod by changing temperature gradient at the liquid/solid interface front and crystallization interval. Central areas with refined microstructure had the highest macro-hardness; stiffer Sc-containing particles further increased the mechanical performances of alloys.
KeywordsBe–Al alloy microstructure mechanical properties vacuum suction casting Sc-alloying
We express our sincere gratitude to Hefei Ji, Qinguo Wang, and Yong Liu for their assistance with instrumental characterization.
- 1.D.R. Floyd, J.N. Lowe, Beryllium Science and Technology (Springer, Berlin, 2014)Google Scholar
- 2.F.C. Grensing, H. Don, Mechanical and thermal properties of aluminum–beryllium alloy AM162. Adv. Powder. Metall. Part. Mater. 3, 13 (1995)Google Scholar
- 3.C. Houska, Beryllium in aluminium and magnesium alloys. Met. Mater. 4(2), 100 (1988)Google Scholar
- 4.J.F. Sullivan, A.C. Haramis, Lockalloy Be-38Al. Mater. Charact. ADA041284, 106 (1977)Google Scholar
- 20.ProCAST™ User’s Manual & Technical Reference, America: ESI Software Inc, 2007Google Scholar
- 28.P. Pawlik, K. Pawlik, A. Przybyl, Investigation of the cooling rate in the suction casting process. Rev. Adv. Mater. Sci. 18(1), 81 (2008)Google Scholar
- 29.W. Kurz, D.J. Fisher, Fundamentals of solidification (Trans Tech Publications Ltd, Aedermannsdorf, 1989)Google Scholar
- 36.E. Niyama, T. Uchida, M. Morikawa, S. Saito, A method of shrinkage prediction and its application to steel casting practice. Int. Cast Metals J. 6(2), 16 (1981)Google Scholar
- 40.Kurz W., Giovanola B. and Trivedi R., Theory of microstructural development during rapid solidification, Acta Metallurgica, 1986, 34(5)Google Scholar
- 45.J.L. Murray, D.J. Kahan, The Al–Be (Aluminum–Beryllium) system. J. Phase Equilib. 4(1), 50 (1983)Google Scholar