INFLUENCE OF SUBMICROSCOPIC STRUCTURE OF “COPPER — BERYLLIUM” ALLOY ON SERVICE CHARACTERISTICS OF ELASTIC SENSING ELEMENTS

The dependence of the properties of elastic sensitive elements made of beryllium bronze on the modes of their heat treatment is studied. It is shown that the duration of aging significantly affects the value of nonlinearity of elastic characteristic, hysteresis, shrinkage of elements and mechanical properties of membrane material (hardness, elastic limit). The relations between submicroscopic structure and properties of elastic elements are established. The greatest nonlinearity of the elastic characteristic, hysteresis and shrinkage belong to elements subjected to short-term aging at 310–350 °С. With increasing duration of aging, the corresponding values of the above parameters decrease. For aging temperatures 310–320 °С, the nonlinearity of elasticity characteristics reaches the minimum values after 4–5 h of aging, and for 340 °С — after 3 h. At 350 °С minimum values of nonlinearity are reached after aging duration of 45–60 min. From the obtained data it follows that from the point of view of obtaining the minimum hysteresis and nonlinearity characteristics of aneroid sensing elements made of bronze of БрБНТ-1,9Мг (BrBNT-1.9Mg) grade, heat treatment of membranes should be carried out according to the regimes of 1 h at 350 °С or 3 h at 340 °С.