SU954489A1 - Steel - Google Patents

Description

FIELD OF THE INVENTION The invention relates to ferrous metallurgy and foundry. in particular, to the search for steel for large castings with high corrosion resistance, with horseback strength and weldability.

Closest to the proposed is steel Cl containing, wt.%: Carbon 0.12-0.18

Silicon 0.20-0.40

Manganese 0.60-0.90

Chrome. 13.0-15.0 Molybdenum0.80.1.10

Vanadium0.002-0.05

Niobium0,002-0,05

Calcium0.001-0.05

Zhelezalstalnoe

The disadvantages of steel are relatively low casting properties, corrosion resistance, ductility and toughness, which reduces the quality of castings made from it.

The purpose of the invention is to increase the casting properties, corrosion resistance, ductility and toughness in case of crush strength.

The goal is achieved by the fact that steel; containing carbon, silicon, manganese, chromium, molybdan, vanadium, niobium, calcium, iron, additionally contains aluminum, titanium, rare earth metals in the following ratios of components, wt.%:

Carbon 0.10g-0.20

Silicon 0.20-0.45

Manganese 0.60-0.90

Chrome 13.0-g1.0

Molybdenum 0,80-1,10

10 Vanadium 0.05-0.15

Niobium 0,01-0,05

Calcium0.005-0.05

Aluminum. 0.01-0.05 titan0.01-0.05

15

Rare earth matal ly0,005-0,08

Iron Else.

In table.1 shows the chemical composition of the experimental steel, smelted

20 to 160 pound induction furnace with acid lining by remelting.

The compositions given are subject to corrosion bone testing in a wet steam environment. Mechanical tests are carried out on conventional samples for tensile strength and impact strength. After homogenization at 1100 ° C with air cooling, normalization at 1000 ° C

30 by air cooling and subsequent tempering when cooled with a stove. The casting properties investigated the fluidity and crack resistance of castings, as the most important casting characteristics, determining the quality of castings. The fluidity is fixed by the method of vacuum suction along the length of a 5 mm quartz tube melt filled with a discharge of 200 mm Hg. Crack resistance is assessed by the total area of hot cracks arising in the thermal unit of the calcite technological sample during its solidification. The test results presented in table 2. From Table 2 it can be concluded that the proposed steel is superior to that of the properties studied according to BceMv. Proposed steel can be recommended for industrial use in addition to what is known in the manufacture of large castings of turbine parts of improved quality. Steelmaking technologists are no different from the known. Some difference lies in the additional deoxidation of steel when casting with aluminum, titanium and SEM. Especially effective deoxidation of steel complex ligatures containing calcium, rare-earth metals, aluminum, titanium, vanadium. The expected economic effect according to preliminary calculations is about 8.5 thousand rubles. per year due to an increase in casting properties by 10–30%, ductility, toughness and corrosion resistance of steel by 1.5 times. Table 1

Table

25

ten

ten

five

Claims (1)

Invention Formula Carbon-containing steel, cream-20, manganese, chromium, molybdenum, vanadium, niobium / calcium, iron, which, in order to improve casting properties, corrosion resistance, ductility and 25 impact strength while maintaining strength, it additionally contains aluminum, titanium and rare-earth metals in the following ratio by component, wt.%: 30 Carbon 0.10-0.20 Silicon 0.20-0.45 Continued table. 2 84 79 20.4 her 62.6 9.5 48.4 6.2 16.2 65 13.8 61 75 43.2 4.8 Manganese 0.60-0.90 Chrome13.0-15.0 Molybdenum 0.80-1.10 Vanadium 0.05-0.15 Niobium 0,01-0,05 Calcium0.005-0.05 Aluminum. 0.01-0.05 Titan0,01-0,05 Rare-earth metals0,005-0,08 Iron Rest Sources of information Considerations in the examination 1. USSR author's certificate 668969, c. C 22 C 38/26, 1979.