The use of rapid electrocontact heating (by an electric current) in quenching dispersion-hardening alloys opens new prospects for substantial improvement of their properties by providing the requisite degree of dissolution of the excess phases with retention of the fine-grained structure of the supersaturated solid solution, which is difficult to attain under the conditions of conventional heating. The advantage of such quenching is connected with the possibility of short-term superheating of the alloy above the temperature of heating for quenching conventionally used. Therefore, such a Ixeala-nent is expedient foremost for alloys that contain poorly soluble excess phases. The present work concerns the role of the heating rate for quenching in formation of the phase composition and slxucture of quenched dispersion-hardening spring alloy 36NKhTYuM8.The composition of dispersion-hardening spring alloy 36NKhTYuM8 has been designed to employ the reinforcing effect of segregation of two intermetallic phases in aging, namely, a y'-phase of the Ni3(Ti, AI) type and a Laves phase ofthe Fe2Mo type [1].The main difficulty in quenching alloy 36NKhTYuM8 consists in dissolution of the poorly soluble Laves phase. The conventional furnace heating (in a protective atmosphere) to 1000-1050~ used in quenching virtually cannot dissolve the excess Laves phase contained in the alloy in any as-received state, and a higher temperature of heating for quenching is not used due to the susceptibility of the alloy to grainThe use of rapid electrocontact heating for quenching alloy 36NKhTYuM8 turned out to be very effective precisely because of the greater dissolution of the excess Laves phase as compared to conventional furnace heating [2]. It has been shown that heating at a rate v h = 300 K/sec to 1200~ with a 6-9-sec hold almost halves the content of the excess Laves phase relative to the initial content with retention of the finegrained structure (d< 15 mm). It has been shown in [2] that rapid quenching is characterized by an unusual kinetics of the dissolution of the excess Laves phase, because the predominant part of this phase dissolves precisely in the heating stage. The dissolution is especially intense if the alloy has been deformed before quenching. Thus, an increase in the heating rate in quenching the alloy can be an important resource of additional intensification of the dissolution of the Laves phase, because it can be accompanied by acceleration of the primary recrystallization and a change in the temperature range of the process [3].We studied the effect of the rate ofelectrocontact heating I in quenching on the phase composition and structural state of alloy 36NKhTYuM8 melted at a plant (0.04% C, 35.5% Ni, 13.5% Cr, 7.82% Mo, 2.93% Ti, 1.16% A1, the remainder Fe).We tested a 0.3-mm-thick ribbon after cold plastic deformation with a 50% reduction (as received). A detailed description of the method of research can be found in [2]. The volume fraction of the particles of the Laves phase in the structure of the alloy was deter...

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