| High-pressure physics has become a very active frontier research of condensed matter physics, with the development of high-pressure science and technology. The high-pressure experiment is not only a means or extreme condition, but a new basic changing dimension for the structure, status and performance of material systems. Rapid compression which is a new high-pressure technology between the static pressure and shock-wave pressure, plays a unique role in preparation of new materials and property measurement of materials. However, it is not clear how the rapid compression method affects the rules such as formation of metastable phase, physical performance et al, during the preparing process. In this research, a high pressure-jump apparatus was used in the study of the amorphous phase formation of Nd60Cu20Al10Ni10 metal alloy, Poly-ether-ether-ketone (PEEK) and some small organic molecules by rapid compression method, expecting to explore the formation mechanism of amorphous materials prepared by rapid compression.Meanwhile, the physical properties of the amorphous materials prepared by rapid compression were charactered. The work includes the following parts:(1) Stable internal heating was improved in Bridgman Anvil. The pyrophylite by calcination at higher temperature was as gasket based on the original design, and its critical thickness and central elastic area were re-evaluated under high pressure. A reasonable size of the sample chamber was investigated and the pressure was calibrated by using Bi. Meanwhile, heater was made of graphite flakes and its middle wire was made of graphite column instead of copper. Temperature calibration was carried out under ambient pressure and high pressure separately. Stable heating was realized within 1300℃under 4.0 GPa. The device will benefit preparation of larger-size amorphous material under higher temperature by rapid compression method.(2) Thermo-stable bulk metallic glass of Nd60Cu20Al10Nii10 was prepared by rapid compression. Melt of Nd60Cu20Al10Ni10 alloy is solidified by rapid compression under different temperature and jump-pressure range.The results indicated that a full bulk metallic glass was obtained by rapid compression from 0.1 to 5.5 GPa at 793K within 20 ms. By comparing with as-cast bulk metallic glass (BMG), it is found that Nd60Cu20Al10Ni10BMG prepared by rapid compression exhibites a higher thermodynamic stability and a paramagnetic property. The relationship between the glass-formation temperature and the pressure in rapid compression for the BMG is demonstrated in the P-T phase diagram.(3) Oversized bulk amorphous poly ether-ether-ketone (PEEK) with three kinds of molecular weight was prepared by rapid compression. Firstly, the melting point of PEEK under high pressure was investigated by differential thermal analysis (DTA), and the result showed that the melting point of PEEK increases with increasing pressure under 1.5GPa. Melts of PEEK were solidified by rapid compression from 0.1 to 2.0 GPa at 360℃within 20 ms, and comparative samples were made by rapid quenching for same melts. The results show that bulk materials of PEEK obtained by rapid compression exhibit a single amorphous phase and high thermodynamic stability. Finally, oversize bulk material of PEEK with molecular weight about 38300 was prepared by rapid compression and rapid quenching separately. A bulk and full amorphous PEEK with 24 mm diameter and 12 mm thickness is prepared by rapid compression, which exceeds much the critical size in conventional quenching method. The results directly confirmed that the size of amorphopus material is not limited by thermal conductivity in the rapid compression process. These results provided a new perspective for understanding the ability of glass-formation of materials. (4) Effect of rapid compression on the mechanical properties of bulk amorphous PEEK was investigated in the article. The melts of PEEK with three kinds of molecular weight were solidified by rapid compression, rapid quenching and natural cooling respectively. And the mechanical properties of obtained samples were characterized by tribological, tensile and impact test. The results indicated that bulk materials of PEEK obtained by rapid compression exhibit excellent friction and wear behavior, considerable stiffness, exceptional ductile character and high impact toughness. These properties could be attributed to their homogenous fine structure.(5) The solidification behavior of small organic molecules was preliminary explored by rapid compression. Naphthalene, Benzophenone and Glucose were as the initial materials according to P-T phase diagram and their melts were solidified by rapid compression respectively. The XRD results showed that the amorphous phase of these samples were not prepared by rapid compression. That maybe because the small organic molecules have a low ability of glass-formation, and the preparation of their amorphous phase need higher pressure range and faster pressurization rate. So the small organic molecules which have been prepared as amorphous phase by quenching method could be used as initial material, and the preparation experiment be carried out on Bridgman anvil which can improve pressure range and pressurization rate in future.
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