SU1415075A1 - Thermocouple - Google Patents

Abstract

The invention relates to thermometry and can be used in measuring devices, as well as in thermostats and thermal switches operating at low temperatures. The purpose of the invention is to extend the measurement range towards low temperatures. When the temperature changes from 300 to 28 K, the bimetallic plate, the active layer of which is made of a single crystal solid solution of substitution CsDy Gdj (MoO) 2, where x 0.04, undergoes bending. At the single-phase phase transition temperature, the magnitude of the bend increases sharply, and its direction may vary depending on the orientation of the single crystal in a direction parallel to the b axis or with 1 or more. $ cl

Description

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about ate

: The invention relates to thermometer; rii and can be used in measuring devices, as well as; thermoregulators and thermostats operating at LOW temperatures.

The purpose of the invention is to extend the measurement range towards low temperatures.

The drawing shows graphs of the temperature dependences of the relative elongations --- (t) of the single crystal

; Cs Dy (,. JjjGd (Moo, respectively, for the three crystallographic axes | a, b, and c.

The thermosensitive element is a bimetallic plate, the active layer of which is made of a single crystal CsDY (Replacement Solvent, Gdj) solution (MoO 1, where x 0.04 (double cesium molybdate mixed with | gadolinium), Second ( the passive) layer of a bimetallic plate can be made of any pure metal, | for example copper, the temperature coefficient | n (3rd expansion (CTE) of which the mvn-JneKTP of the material of the active layer. With a temperature change from 300 to 28 K due to the difference between the CTE of active and passive bimetallic layers while undergoes bending, | whose value increases sharply near the first order transition temperature - T 28 K material

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active layer in connection with a jump in volume and, accordingly, the linear dimensions of a single crystal

In the temperature range 28–30 K, the thermoelement can operate in the key mode, which is ensured by

L1 / V

jumps - (TJ and, therefore, the derivative N, (t), which increases or decreases in the transition region by 4-10, 7 and 8 times, along the crystallographic axes a, b and c, respectively

Depending on the orientation of the active layer in the direction parallel to the b or c axis, the bimetallic plate can be bent in different directions in the phase transition region Tj, which is caused by a decrease or increase in the size of the single crystal in the basal plane, respectively, along b and c axes.

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the invention

Thermosensitive element containing a bimetallic plate, aphidizing by the fact that, in order to extend the measurement range towards low temperatures, one of the layers of the bimetallic plate is made of a single crystal CsD Gd (MoO.) 2 e solid solution where X 0.04 o.

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Claims (1)

Claim Tehred M. Khodanich. A thermosensitive element containing a bimetallic plate, characterized in that, in order to expand the measurement range towards low temperatures, one of the layers of the bimetallic plate is made of a single crystal of a substitutional solid solution CsD ^ Gd * (Mo0 ₄ ) ₂ . Corrector C <, Sheckmar. Circulation 607 Subscription VNIIIPI of the USSR State Committee for Inventions and Discoveries 113035, Moscow, Zh-35, Raushskaya nab ”, d. 4/5. Production and printing company, Uzhgorod, st. Project, 4.