Dynamic shock wave processing on β-MnMoO4 ceramic micro-sized crystals and its structure-morphology-property relations

In the present work, we perform a few shock-wave-processing experiments on typical ceramic materials of β-MnMoO4 (P2/c) by the exposure of 0, 100 and 200 shocks, respectively, and investigated their structural, optical and morphological features to materialize the effect of shock waves. Under shocked conditions, the title sample does not undergo any crystallographic phase transitions of either to α or to ω phases. However, several modifications are noticed in the mother phase such that the diffraction intensity ratio of (1-11)/(111) is found to have increased with respect to the number of shock pulses and the observed values are 0.85, 1.07 and 1.36 for the exposure of 0, 100, 200 shocks, respectively. Under the 200-shocked condition, the sample's intensity ratio is found to be closely matched to the standard pattern of the test sample with the P2/c space group. In morphological aspects, the control sample's wolframite structure has slight morphological deformations whereas the 200-shocked sample has an almost ideal morphology of the wolframite structure. Optical property results demonstrate a slight enhancement of the optical transmittance in the UV–Visible and NIR regions along with a blue shift at the 200-shocked condition. The above-mentioned analytical results reveal that the applied shock waves have effectively induced the thermal softening process, reducing the lattice and surface stresses on the test sample. A detailed discussion on the triangle relation of the structure-morphology-property of the control and shocked samples is provided.