All industrial alloys of the AI-Mg system correspond to the region of the a-solid solution of the phase diagram. Domestic alloys AL8 and AL27-1 and foreign alloys 520 (USA) and LM-10 (Great Britain) with a high magnesium content (9 -11%) have high mechanical properties after quenching. However, they possess a high sensitivity to natural aging under conditions of long-term operation or storing, which causes their embrittlement. The aim of the present work consists in developing an AI-Mg-base composition quenched and aged artificially that will possesses a high strength (err = 380-400 N/ram 2) and will not change in operation at a temperature of at most 100~We chose alloy AL27-1, which is the strongest domestic alloy of the AI -Mg system for our study. In order to choose an optimum composition we used the method of experiment design with a Schaeffer simplex lattice of the third order. Figure I presents the dependences of the mechanical properties of quenched alloy AL27-1 (10.2% Mg, 0.08% Ti, 0.11% Zr, < 0.05% Fe, < 0.l% Si, the remainder AI) on the regimes of artificial aging. After quenching from 435 + 5~ (20h) in water with G=100~ the alloy has G = 375 N/mm 2, 8 = 22.0%. An analysis of the obtained results has shown that artificial aging in the studied range of tema t, ~ peratures and hold times does not cause an additional oo ~xyg~ strengthening of the quenched alloy. An increase in the hold temperature and time for every temperature of artificial aging 2 ~ ~ N/ram2 decreases the strength and the elongation of the quenched alloy, i so~/ ~a~ In accordance with triple-phase diagrams we introduced /%N2\ additional elements into the binary AI-Mg alloy in combi-100.,/ ]G.~-----~-N-..,~ nations and amounts that would prevent the formation of an embrittling !3-hase, namely, 6 -16% Mg, 0 -5% Zn (in order so. to increase the strength), O-2% Mn (in order to decelerate 6 27 ~, h 48 the diffusion processes of the decomposition of the solid sot, ~ lution and increase its stability), O-2% Sb (in order to inoo "~ a, crease the stability of the solid solution, improve the corro2oo sion resistance and decrease the crack formation), and 0-~ 0.05% Zr (in order to disintegrate the structure). After the exis0~-~14 x periments and a mathematical analysis of the results we have chosen an optimum composition for the alloy.Ioor 20 ~--~\ We conducted a comparative metallographic and differ-/ ential thermal (DTA) analysis of alloy AL27-1 and an experi-50.L 6 2'7 48

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This article observes the tendency of active introduction to the literary language (literature, drama, media and internet­publications) of dialect lexica, derivations var­iants and grammatical forms. By reconstructing the borders of the most popular dia­lectic units on the maps, there is making conclusion about the regional influence and transformation of dialectal base of the Belarusian language.

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