中国科学院地球化学研究所机构知识库

Superheating-assisted melting and crystallization are prominent subjects in condensed matter physics.However, understanding the superheating concepts under acoustic shocked conditions remains a mystery.Herein, we demonstrate superheating on the basis of dynamic recrystallization in a D-tartaric acid powder sample, which nearly attains an ideal crystal structure and morphology under the 100-shocked conditions compared to the control sample and the obtained results are evaluated by conventional diffraction,
spectroscopic and microscopic techniques. From the XRD results, the intensities of the planes (100) and (110) are found to have increased under the 100-shocked conditions, whereas the intensity ratio (011)/(110)has been significantly reduced. Moreover, the intensity ratio of major internal Raman modes such as vC–O (1694 and 1700 cm1), vC–H (2933 and 2967 cm1) and vO–H (3331 and 3403 cm1) has been considerably modified with respect to the number of shock pulses such that the sample produces an ideal Raman spec-trum of D-tartaric acid, and thereby the intensities of the lattice Raman modes also support this claim. Most importantly, the SEM results demonstrate the formation of an ideal morphology of D-tartaric acid from the irregular morphological pattern upon exposure to 100 shocks due to the superheating and dynamic recrys-tallization process. The proposed technique is strongly suggested for materials processing to enhance tech-
nological significance for all classes and scales of materials.