Introduction

Abstract

In recent years the use of the pressure parameter in materials research has increased enormously. It is probably true to say that the growth rate in the 1960s compares favourably with that of liquid helium temperature research in the 1950s. It has been estimated that there are of the order of three hundred laboratories actively engaged in making high pressure measurements, and nearly six hundred papers on the subject were published in 1965. By far the greatest growth has been in the United States and the National Bureau of Standards has set up a data centre at Brigham Young University, Utah, to compile all published high pressure work. In other countries the growth rate has been at a lower level, although in the USSR the Institute for High Pressure Research of the Academy of Sciences, Moscow, has been to the forefront in this field for many years. Probably the most important event has been the synthesis of diamond at high temperature and high pressure by General Electric Co., (U.S.A.) and by A.S.E.A. Co. (Sweden) and its wide economic consequences. The basis of the most important techniques in high pressure research were worked out by the late P. W. Bridgman and the debt to him will be obvious from the descriptions given in the remainder of this book.