Features of the formation and development of scientific research in the laboratory of physics of interfacial phenomena in ChISU named after L. N. Tolstoy in the 1970-1980s of the last century are considered in this paper. Particular attention is paid to the development and improvement of various methods for measuring the density of liquid metals and alloys. We determined the contribution of ChSU scientists in the study of metals and alloys properties and gave a scientific assessment of the obtained results. The development of methods and techniques for measuring the density of liquid metals and alloys went in two directions. Primarily, we took significant steps towards improving the accuracy of density measurements. The instruments were designed in which the accuracy of measuring density and, in particular, the temperature coefficient of density was significantly increased. Foremost, this concerns advanced pycnometers and areometers designed in ChSU laboratories. The instruments received inventor's certificates, and they were awarded the bronze medal of the Exhibition of Achievements of National Economy in 1977. The second direction improving the measuring technique of the metal properties is characterized by instrument designing for the joint measurement of physico-chemical properties in the same thermal vacuum conditions. Both areometers and pycnometers were used to determine density in these instruments.