高压物理学报

Microstructure Damage of Glasses under Shock Wave Compression

HE Hong-Liang, JING Fu-Qian, JIN Xiao-Gang, KANEL G I

1998, 12(4): 241-249 . doi: 10.11858/gywlxb.1998.04.001

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Abstract:
Experimental measurements were conducted for the shock compressed glasses at the stresses below their Hugoniot elastic limit ( HEL ). It has been revealed that, in terms of the microstructure damage degree, there exist two different regions within the stressed samples: a compressed (without damage) and a fractured regions, respectively. Results of K9 and ZF1 glasses with double-layer structure sample demonstrate that the formation of the fracture region could be due to an activation and development of the primary microcracks on glass surface under shock wave compression, which is the first cause. Besides, due to the different compressibility between the matrix and the inhomogeneous phases distributed in the original glass body, numerous locally strained spots would be produced under shock wave compression. When the surface microcracks propagate to the strained spot boundaries, new cracks are generated, accompanying with crack turning and branching, which makes glass body further fracture of fragmentize.

Crystalline-Amorphous Transition of LiB3O5 under High Pressure

CHEN Liang-Chen, WANG Li-Jun, GU Hui-Cheng, LI Feng-Ying, ZHOU Lei, CHE Rong-Zheng, XIU Li-Song

1998, 12(4): 250-253 . doi: 10.11858/gywlxb.1998.04.002

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Abstract:
Pressure induced amorphous transition of LiB3O5 (LBO) has been investigated by using in situ high pressure X-ray powder diffraction and energy dispersive X-ray diffraction with synchrotron radiation at the pressure up to 45.1 GPa. According to the experimental results, LBO undergoes two intermediate phase transitions at pressure of about 5 and 15.8 GPa, respectively. But LBO crystal becomes an amorphous phase in the pressure range of about 25～31.6 GPa and this amorphous transition is irreversible.

Equation of State, Electrical Properties and Phase Transition in CuO at High Pressure

BAO Zhong-Xing, CHENG Kai-Jia, ZHAO Chang-Sen, CHENG Shu-Yu, LIU Cui-Xia, CAI Zong-Yi, LI Yan

1998, 12(4): 254-257 . doi: 10.11858/gywlxb.1998.04.003

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Abstract:
The p-V relationship for CuO at room temperature and up to 4.5 GPa has been studied using the piston-cylinder type measurement device, and its equation of state, Grneisen parameter 0, bulk modulus B0 and the first order pressure derivative B0' have been given. And the resistance-pressure and capacitance-pressure relationships at room temperature and the pressures up to 22 GPa have been studied in a diamond anvil cell using resistance and capacitance measurements. Experimental results show that several anomalous changes in resistance and capacitance occur. We conjecture that the change at about 5 GPa may be caused by the change of the interior electronic structure (electronic structure transition), and the changes at other pressures may be related to the changes of structures of states in the crystal boundary. These results are valuable to understand the mechanism of superconductivity for the copper-bearing oxide superconductors.

Shock Compressive Properties of Three Tungsten Alloys

WANG Jin-Gui, LI Xin-Zhu, WANG Wei, FU Qiu-Wei, WANG Xiang

1998, 12(4): 258-263 . doi: 10.11858/gywlxb.1998.04.004

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Abstract:
A deviation controlling technique was described in this paper, with which Hugoniot curves of three tungsten alloys have been obtained with higher accuracy. A comparison with the prediction of superposition calculation is very suitable for the principle of superposition exhibits that the shock compression of high weight percentage tungsten alloy.

The Rectangular Diffraction of Detonation Wave in the High Explosive RHT-901 and the Insensitive High Explosive IHE-2

ZHAO Tong-Hu, HAN Li-Shi, HE Zhi

1998, 12(4): 264-270 . doi: 10.11858/gywlxb.1998.04.005

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Abstract:
The patterns of rectangular diffraction of detonation in the high explosive RHT-901 and the insensitive high explosive IHE-2 have bean measured with the rotating mirror framing camera and the coaxial ionization probes techniques. Results show that (1) the reaction is incomplete near the convex angle in IHE-2; (2) the radius of the curvature of the diffractive detonation wave front in RHT-901 is larger than that in IHE-2 and (3) the diffraction of the detonation has relation with the width of reaction zone and the sensitivity of the explosive.

Equation of State of Detonation Product (Ⅰ)－Detonation Heat, Isentropic Equation and Equation of State of Detonation Product

LI Yin-Cheng

1998, 12(4): 271-281 . doi: 10.11858/gywlxb.1998.04.006

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Abstract:
In this paper, it attempts to clarify some doubtful points existed currently which are related to detonation heat, isentropic equation and equation of state of detonation product.

Numerical Simulation for the Propagation of Thermal Shock Waves Induced in Materials Irradiated by Pulsed Electron Beam

PENG Chang-Xian, XU Yong-Liang

1998, 12(4): 282-290 . doi: 10.11858/gywlxb.1998.04.007

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Abstract:
We have made numerical simulations of the propagation of thermal shock waves induced in aluminum alloys irradiated by the electron beam on FLASH-Ⅱ, adopting an analytic method of the energy deposition, the constitution relation of material in low-pressure zone and one-dimension strain model of the elastic-plastic hydrodynamics. The computed results show that the computed values are in basically agreement with the measured.

Study on the Shock Compression of Foam Silicon Rubber

LI Xin-Zhu, WU Qiang, ZHANG Han-Zhao, WANG Xiang, ZENG Jian-Rong

1998, 12(4): 291-297 . doi: 10.11858/gywlxb.1998.04.008

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Abstract:
An investigation has been carried out for the shock compression of the foam silicon rubber (FSR) with initial density of 0.92 g/cm3. In the pressure range from 6 GPa to 33 GPa, the Hugoniot relation between shock velocity D and particle velocity u has been obtained: D=1.686+1.367u. Compared with the relative results published previously, it is demonstrated that our experimental data are reasonable and have higher precision. Manganin gauges have been used in the experiments to determine the shock pressures, of which the signals differed greatly from the normal ones. The reasons for this phenomenon are analyzed carefully and further verified via 1D simulation. Moreover, the W-J model which is independent to our experiment thoroughly has been applied to predict the shock compression of the FSR. The prediction has a good agreement with the experimental results. It shows that the W-J model is suitable not only for metals or minerals but also for porous polymer.

Pressure Induced Crystallization of Polyamide-6 from the Melt

Lü Yun-Wei, HUANG Rui, XIE Bang-Hu

1998, 12(4): 298-302 . doi: 10.11858/gywlxb.1998.04.009

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Abstract:
A study has been made on the crystallization of polyamide-6 from the melt under high pressure. The morphology and structure has been investigated by means of differential scanning calorimetry, wide angle X-ray diffraction and scanning electron microscopy. The experimental facts show that during the crystallization of polyamide-6 under high pressure, the size of the crystal as well as the crystalline order have increased considerably, and extended chain crystal has been grown.

Nano-Crystalline Diamond Prepared by Laser Ablating Solid Target in Liquid

WANG Jin-Bin, LIU Qiu-Xiang, YANG Guo-Wei, CHEN Xiong-Qun, YOU Jian-Qiang

1998, 12(4): 303-306 . doi: 10.11858/gywlxb.1998.04.010

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Abstract:
Nano-crystalline diamond has been prepared by laser ablation method in which graphite target is ablated by high-power pulsed-laser in acetone solution. Transmission electron microscopy (TEM) and high resolution electron microscopy (HREM) indicate that nano-crystalline diamonds have hexagonal lattice and cubic lattice.

1998 Vol. 12, No. 4

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