| As a prosperous method for material science research, the technology of shock wave loading is becoming more and more emphatic. This technique is being widely used to find the relations on component, construction and performance of materials under the super-pressure, and to discover the new forms of matters and high-pressure metastable phases. The normally used shock wave loading and recovery devices can be divided into two forms: planar or cylindrical, producing shock wave less than 100 GPa on the materials. For getting higher shock pressures, more interest is now being paid on trying to use the spherical converging shock wave and get super-pressure. This paper is to study the super-pressure loading and recovery device that can intensify the shock wave based on the principle of quasi-spherical converging shock wave. Through a systematic research and experimental validation on the detonating method, the device structure, the recovered sphere and sample, we have successfully established a quasi-spherical converging shock wave loading and recovery device that can produce a pressure more than 300 GPa, with low cost and high reliability on sample recovery, and obtained some rule and knowledge on the factors that influence the converging of shock wave. In addition, we demonstrate with this paper the synthesis of some new materials by using this spherical device and other conventional set-ups (planar and cylindrical ones). Followings are some conclusions: 1. The construction of the spherical device consists of three parts: centre steel sphere, spherical shell explosive and steel spherical outer shell. It is detonated synchronously with 12 spots evenly distributed on the explosive surface, and the testing material sample is placed inside the steel sphere. Among 12 tests, except one which lost sample because of the sphere broken since too much explosive, all the other tests were successful, showing that the quasi-spherical converging shock-wave device has reasonable design, good practicability and well reliability. According to the theoretical calculation on pressure and combing with the observation of the metal phase changes from the recovered sphere, the device has produced a pressure more than 300GPa in the centre of the sphere, which providesa condition for studying the material's construction, performance and physical/chemical reaction under super pressure and temperature.2. To realize the 12 points synchronized detonating, the simplest way is to use 12 high-synchronized detonators, but the cost will be quite high. In our device, we have used 2 high-synchronized detonators to detonate 12 mild detonating fuse (MDF) that then initiate 12 boosters on the explosive shell, making 12 spots synchronously detonated. The shock wave has made a nearly standard dodecahedron pattern on the surface of centre sphere. This pattern is the result of shock waves interaction from two adjacent detonating spots, and its position shows how the detonating of two adjacent spots acts, synchronized or not. The nice dodecahedron stroke patterns on the surface of recovered centre sphere indicate that this detonating method has good synchronization and spherical converging shock-wave. This method not only has guaranteed a good shock wave convergence, but also drops a lot of cost for the experiment.3. Different kinds of explosive have big influence on the practicability of the device and on reliability of recover of material samples. This paper has compared JQ-9159 solid explosive and nitromethane liquid explosive experimentally. Based on the analyses of symmetry and deepness of stroke pattern made by two explosives on the recovered sphere surface, we conclude that: the liquid explosive is better for sample recovery and shock wave converging. Though the solid explosive has high exploding power, could get higher shock pressure, but it makes deeper stroke pattern on recovered sphere, and produces more destruction to the sphere. In the view of recovery device, the shock pressure intensif...
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