The geometric and crystallographic characteristics of interfaces in WC–Co composites with a range of grain sizes and carbide volume fractions have been comprehensively characterized. The carbide crystals are most frequently terminated by (0001) and surfaces. The average number of carbide vertices per grain and the basal‐to‐prismatic face area ratio of the WC–Co interfaces increase with the carbide volume fraction. The three most frequently occurring WC/WC grain boundaries are 90° twist boundaries about , 30° twist boundaries about [0001], and asymmetric 90° boundaries about. The boundary populations do not vary with grain size or carbide volume fraction, suggesting that they are determined by the grain boundary energy anisotropy.

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Two‐dimensional finite element simulations were used to study the effects of orientation texture on the transverse rupture strengths of WC–Co composites. The model incorporates observed microstructural geometries, anisotropic thermal and elastic properties, and a fracture criterion that reproduces the strengths of known specimens. The results show that the greatest potential for increasing the strength occurs when the [001] axes of the carbide grains are orientated perpendicular to the sample loading direction. Furthermore, the strength increases in proportion to the degree of texture, and the texture‐derived strength enhancement is greater in microstructures with a larger contiguity.

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A typical boring bar is a metal cutting tool with large overhang ratio, due to which it is characterized by low dynamic stiffness. Therefore, during cutting process, it is susceptible to cutting instability, known as machine tool chatter. In this paper, the use of an active dynamic absorber to actively control machine tool chatter in a boring bar is studied. An active dynamic absorber is designed such that it can be easily assembled with a commercially available steel boring bar. A piezoelectric pusher is used as the actuator for the active dynamic absorber. The dynamic equations of the boring bar with active dynamic absorber are calculated from experimentally obtained frequency response functions of the system. Optimal control theory is applied to the dynamic equations to calculate state variable feedback parameters. The state variable feedback is implemented using a Digital Signal Processing (DSP) chip. Cutting tests were performed with this setup for different cutting conditions, and for different overhangs of the boring bar. Stable cutting operations were performed using the boring bar with active dynamic absorber, for length to diameter (L/D) ratio upto 9.