Development of Very High Strength and Ductile Dilute Magnesium Alloys by Dispersion of Quasicrystal Phase

• Published in: Metallurgical and materials transactions. A, Physical metallurgy and materials science Vol. 45; no. 8; pp. 3232 - 3240
• Main Authors: Singh, Alok, Osawa, Yoshiaki, Somekawa, Hidetoshi, Mukai, Toshiji, Parrish, Catherine J., Shih, Donald S.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Boston Springer US 01.07.2014; Springer; Springer Nature B.V
• Subjects: Alloys; Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Dilution; Exact sciences and technology; Extrusion; Failure; High strength; Magnesium; Magnesium base alloys; Materials Science; Mechanical properties; Metallic Materials; Metallurgy; Metals. Metallurgy; Nanostructure; Nanotechnology; Physical metallurgy; Structural Materials; Surfaces and Interfaces; Symposium: Processing-Microstructure-PropertyRelationships & Deformation Mechanisms of Magnesium Alloys; Tensile strength; Thin Films; Magnesium Alloy; Ductility; Ternary Phase; Extrusion Direction; Total Elongation; Dilute alloy; Development; Quasicrystal; Strength
• ISSN: 1073-5623; 1543-1940
• DOI: 10.1007/s11661-013-2056-5

Very high strengths, with tensile yield strength from 377 to 405 MPa, combined with elongation to failure of over 12 pct, have been achieved in Mg-Zn-Y dilute alloys by direct extrusion. Alloys Mg-6 x Zn- x Y, where x  = 0.2, 0.35, and 0.5 (at. pct) were chill cast in a steel mold and direct extruded at a temperature in the range 508 K to 528 K (235 °C to 255 °C), which produced an average grain size of about 1  μ m. Quasicrystalline i -phase particles were dispersed in the matrix with size ranging from 50 nm to 1  μ m. In addition, high density of nano-precipitates of average size 15 nm was dispersed in matrix. Thus we have developed magnesium alloys of very high strength combined with ductility by a simple process using extrusion with very little addition of yttrium.