The microstructure and properties of rapidly solidified AlHf alloys

✍ Scribed by A.F. Norman; P. Tsakiropoulos

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 421 KB
• Volume: 134
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/0921-5093(91)90963-n

✦ Synopsis

AI-Hf alloys were produced by chill casting and gas atomization. The solid solubility of hafnium in aluminium was extended to 2 wt.% Hf in the sub 45/zm size powders. Precipitation of the L12-AI3Hf phase refined the chill cast grain size from 300 /zm to 5 /~m. The powders were consolidated by extrusion and their tensile properties were evaluated at room temperature after ageing at 300 °C for up to 1000 h. Decomposition of the solid solution at 300 °C occurred by continuous and discontinuous precipitation of the L12-A13Hf phase. Precipitation strengthening contributions by the spherical and filamentary type precipitates and solid solution strengthening have been calculated.