Dynamic Young`s modulus and internal friction in particulate SiC/Al composites

摘要: Abstract Anelastic behavior of an SiC particulate reinforced aluminum composite has been examined through the measurements dynamic Young's modulus and internal friction over a temperature range from 25 to 450°C at frequencies 0.01, 0.05 0.1 Hz. A standard servo-hydraulic mechanical testing machine equipped with infrared lamp heater was employed, but measurement system therein especially designed by assembling scanning laser extensometer frequency response analyzer for detecting amplitude phase lag strain in sinusoidal time-varying stress. Two broad peaks were observed ranges 100 250°C (LT peak) 250 400°C (HT peak), together marked decreases same ranges. From quantitative analysis experimental data, it is concluded that HT peak phenomenon due grain-boundary relaxation, whereas LT ascribable relaxation caused stress-directed interfacial diffusion Al atoms along particle-matrix interface.