Metal Matrix Composites Reinforced With Intermetallic Ribbons

Abstract

The design procedure for low melting point alloy composites reinforced with melt-spun intermetallic ribbons for elevated temperature applications is presented. Long·range ordered Ni 3A1 intermetallic is selected as a candidate reinforcement by virtue of its ease of being ductilized by boron and an increase in yield strength with increasing temperature. A certain composition of Ni 3A1 alloyed with cobalt, tantalum, hafnium and boron for the maximum reinforcing effect is formulated. The rule of mixtures calculations of elastic modulus and yield strength are performed for AI-Si and Mg-AI matrices. The results of the structural investigation of a model composite system consisting of a tt 00 AI matrix with embedded Ni7SAl23Zr181 (a1.%) ribbons, obtained by casting, are presented. Lonq-terrn stability of the reinforcing ribbons is investigated by annealing of "as-cast" specimens at elevated temperatures up to 100 h.

Mechanical and Tribological Properties of Ti3Al Reinforced Aluminium Matrix Composites

“…Intermetallics have very interesting properties to be used as reinforcements in aluminium based composites: high strength, modulus, and thermal stability [3]. One of the first investigations on this combination was made by Varin [6] and continued by other authors [7][8][9][10][11] but were primarily focused in the use of Ni 3 Al intermetallic particles. In further works by the authors [12,13] titanium aluminides were presented as a quite promising reinforcement.…”