ELASTIC-MODULUS AND VIBRATION DAMPING IN IRON COPPER-BASED AND STEEL-BASED METAL-MATRIX COMPOSITES/

Measurements were made of the dynamic flexural modulus, dynamic Young' s modulus, damping, strain amplitude, and the strain amplitude depende nce of damping in iron/copper- and steel-based metal matrix composites . Comparisons were made concerning the steel matrix specimens before a nd after heat treatment. The flexural modulus tests were performed usi ng the Grindosonic technique, while the Young's modulus, damping, stra in amplitude, and the strain amplitude dependence of damping were dete rmined using the piezoelectric ultrasonic composite oscillator techniq ue (PUCOT). Metallographic studies utilizing chemical etching, optical and electron microscopy, and microhardness testing were performed to assess the distribution of the fibres in the composites. The variation of dynamic Young's modulus with respect to percentage copper in the c omposites followed the rule of mixtures.