Microstructure and mechanical properties of nanostructured A8006 ribbons

The microstructure and mechanical properties of nanostructured A8006 ribbons produced by melt spinning technique were investigated using an electron microscopy and micro-tensile and hardness testing. The cooling rates of as melt-spun A8006 ribbons with secondary dendritic arm spacing of 0.7-1.0 μm were estimated between 1.22 × 105 K s−1 and 4.14 × 104 K s−1. The morphology of nanostructural Al13Fe4 precipitates of the melt-spun ribbons after heat treatment was changed from fine and dense (500 °C/8 h) to large and sparse (580 °C/4 h). The increase in tensile properties and hardness of as melt-spun ribbons is related to the supersaturatured α-Al solid solution and fine microstructure. The decrease of the mechanical properties after heat treatment can mainly be attributed to Al13Fe4 precipitation and the subsequent growth. The as melt-spun ribbons presented a dimple-type ductile fracture different to that of the heat treated ribbons, which showed a brittle fracture surface.