SU1476352A1 - Device for determining surface tension of solid body - Google Patents

Abstract

The invention relates to instrumentation engineering, in particular, to devices for determining the physicochemical characteristics of a solid, in particular its surface tension, and can be used, for example, in physical chemistry, metallurgy. The aim of the invention is to simplify the method for determining the surface tension of active metals by eliminating the need for preparatory operations with the sample outside the chamber. For this purpose, a node is mounted on the lid of the measuring chamber for receiving and directly entering it and its wire sample by extrusion of the metal under study. The free end of the sample is fixed in the measuring chamber by melting it. 1 il.

Description

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The invention relates to a measuring and control technique, namely, devices for determining the physicochemical characteristics of a solid, in particular its surface tension, and can be used in physical chemistry, metallurgy, as well as in solving technological problems of crystallization, soldering and welding.

The purpose of the invention is to simplify the determination of the surface tension of the active metals by eliminating the need for preparatory operations with the sample outside the chamber.

The drawing shows a diagram of the device.

A device for determining the surface tension of a solid contains a measuring chamber 1 with windows 2, on

the cover 3 of which is arranged a device for receiving and inserting a wire sample into the chamber by extrusion of the metal under study. This device includes a pressing device 4, a container 5 for the extruded metal and a die 6. On the lid 3 of the measuring chamber 1 there is also a tap 7 for creating a vacuum or inert atmosphere in the chamber 1, a current lead 8 for the thermocouple 9, two spiral micro-ovens - working 10 and auxiliary 11, a vacuum inlet 12 of rotation, on the rod 13 of which a mechanical lever 14 with a weight 15 is fixed by its axis. One shoulder of the horizontal mechanical lever 14 is connected to sample 16, and the other is connected to a string strain gauge, including 1

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The string 17 and the piezoelectric element 18 are on the stem of the microscrew 19. The latter serves to set the mechanical lever 14 to the working (horizontal) position, and the weight 15 on the lever 14 provides the preloading of the string 17.

The device works as follows.

To load the metal under investigation into the container 5, the lid 3 of the measuring chamber 1 with the metal extrusion device is placed in a sealed box (not shown) blown by an inert gas. Compact metal samples are removed from the protective liquid, washed in appropriate anhydrous solutions, transferred to container 5, and pressed with a pressing device 4 before extrusion. The moment of the start of metal outflow in the solid state corresponds to the vacuum compaction of the die plate 6 with the material to be extruded, which makes it possible to remove the cover 3 from the box, place it on the chamber 1 and pump the latter out to a high vacuum. To obtain a metal wire extruded, pre-pull the mechanical lever 14 to the side by entering the 12 rotation. As the metal is extruded, the purity of the resulting wire increases. This is due to the fact that so-called stagnation zones are formed at the walls of the container 1 and the inlet cone of the die 6 and the outflow of metal comes from the bulk of the massive sample. After stopping the extrusion process, the contaminated part of the wire is removed by melting with the help of auxiliary micro furnace 11. With the same furnace

For fixing the lower end of the wire sample 16 in the body of the mechanical lever 14.

Next, the sample is annealed using a micro furnace 10 and the necessary measurements of the natural frequencies of the string oscillations to find the force on the lever, as required by the zero-creep compensation method for determining surface tension.

Claims (1)

Invention Formula A device for determining the surface tension of a solid containing a measuring chamber with a lid in which a horizontal mechanical lever is placed, one end of which is connected to a compensation system and measuring the force acting on this end, a micro-furnace for local heating of the sample, located in The chamber above the second end of the lever, characterized in that, in order to simplify the determination of the surface tension of the active metals by eliminating the need for preparatory operations with the sample outside the chamber, a device for receiving the wire sample by extruding the test metal is installed in the measuring chamber lid into the measuring chamber, the axis of the mechanical lever is fixed to a vacuum vacuum input rod, and a second micro furnace is installed under the second end of the lever.