Equations of state of some standard materials and the ahsolute tigh-pressure scale

本文的目的是获得若干标准物质在多个Terapascal压力下状态方程的实验参数，并建立绝对高压标度。为了产生多个两帕斯卡的压力，需要一个高速加速装置来实现平板状材料的对称撞击。该设施是我们在七年前建造的三级轻气炮，建造后得到了很大的改进。在这项研究中，一些操作的时间抖动同步快速运动的重型机械部件减少和确认。然而，由于氢气的冷却和枪管的腐蚀严重，加速度没有显著增加。另一方面，为使这种小型气炮能用于精确的状态方程实验，发展了一些新技术：一种是方便、精确的状态方程实验技术，另一种是在实验室中进行的状态方程实验技术。 ...更多信息 一种是用于测量材料中冲击波速度的光纤传输型线激光反射系统。前者是基于由首席研究员最初开发的事件前脉冲发生器，该系统可以产生具有几纳秒时间分辨率的飞行器的定时触发脉冲，并且不需要在目标上布置触发针。因此，该系统使得目标尺寸与飞片一样大成为可能。在铜对称撞击情况下，当撞击速度为6.5km/s时，高压Hugoniot参数的绝对误差为± 0.5%，而在撞击速度为6.5 ~ 8 km/s时，由于靶和飞片的变形，高压Hugoniot参数的绝对误差为± 2%或3%。为获得多兆帕斯卡的高压标准数据，还需在火炮操作优化、靶组件加固等技术问题上加以改进。少

The objectives are to obtain experimental parameters for equations of state of some standard materials at pressures of multi-terapascal and to establish the absolute high-pressure scale. We need a high-velocity acceleration facility for symmetric impact of flat-plate-shaped materials in order to generate multi-terapascal pressures. The facility is a three-stage light-gas gun which was constructed by us seven years ago and was much improved after the construction. In this study, some operational timing jitters for synchronizing quick motion of heavy mechanical parts were reduced and confirmed. Since, however, the cooling of hydrogen gas and the erosion of a gun barrel were serious, remarkable increase of acceleration was not achieved. The projectile velocity of 10 km/s for a pressure of 1 TPa was not achieved.On the other hand, some new techniques were developed for such compact gas gun to be employed for accurate and precise equation of state experiments ; one is a convenient and preci … More se timing system, and the other is a fiber-transport-type line-laser reflection system for measuring shock velocity in materials. The former is based on the pre-event pulse generator which was developed originally by the head investigator ; the system can generate a timing trigger pulse which has a few nanoseconds time-resolution by the flyer and does not need a trigger pins arrangement on the target. Therefore, the system makes it possible that the target size is as large as the flyer. The latter also makes it possible to observe flyer distortion and tilt and target deformation due to escaped acceleration-gas.The absolute error of high pressure Hugoniot parameters was +/- 0.5% upto impact velocity of 6.5 km/s in the case of copper symmetric impact, but +/-2 or 3% between impact velocities of 6.5 and 8 km/s due to the both of deformation of target and flyer. We need to improve some technical issues such as optimization of gun operation and reinforcing of target assembly in order to obtain high-pressure standard data for multi-terapascals. Less