FIELD: machine building; metallurgy; agricultural production.
SUBSTANCE: invention relates to a method of improving reliability of cast-iron anchor plowshares of stubble seeders using thermal treatment. Method includes melting, alloying and modifying cast iron, obtaining a cast into a sand mold, removing the cast from the mold at a given temperature, moving into a liquid bath with a given temperature, wherein cast iron containing, wt.%: C 3.2–3.3, Si 2.0–2.2, Mn 0.5–0.6, Ni 1.5–1.6, Mo 0.9–1.1, Cr 1.1–1.3, Cu 1.2–1.4, Mg 0.04–0.05, Co 0.2–0.25, Ti 0.2–0.25, Ba 0.06–0.08, Al 0.02–0.03, Ce 0.01–0.02, S≤0.08, P≤0.08, Fe—the rest, is removed from the mold at temperature of 950–1,020 °C and moved into a bath with water with temperature of 20 °C, wherein heat treatment is carried out by four cycles of immersion and extraction of the cutting part of the anchor ploughshare, at that, at the first cycle, the cutting part is immersed in water and held for 2.7 s, then extracted and held in air for 3.9 s, at the second cycle, immersed in water and held for 2.3 s, then extracted and held in air for 4.7 s, in the third cycle, immersed in water and held for 1.5 s, then extracted and held in air for 9.8 s, at the fourth cycle, immersed in water and held for 1.0 s, then extracted and held in an air medium until complete cooling, wherein at the first cycle the cutting part is immersed in water with a plane from the upper frontal angle of the first bulge from above to perpendicular to middle of distance from lower part of second thickening from above to lower down suction, relative to installed state, and on the second and subsequent cycles, the cutting part is immersed in water from the upper frontal angle of the first bulge from above to the lower down suction, relative to the established state.
EFFECT: zonal distribution of metallographic structures on functional zones of anchor plowshares of stubble seeders in accordance with type of prevailing loads.
1 cl, 2 dwg, 1 tbl, 2 ex
