Heat resistant steel for sintering machine grates

Abstract

The invention discloses heat resistant steel for sintering machine grates. The heat resistant steel comprises chemical components, by weight percent, including 0.08-0.12% of C, 0.6-0.8% of Si, 1.2-1.4% of Mn, 12.0-14.0% of Cr, 1.3-1.5% of Mo, 0.5-0.7% of W, 1.5-1.7% of Co, 0.10-0.12% of V, 0.05-0.07% of B, 0.2-0.4% of Nb, 0.08-0.10% of Ti, not less than 0.03% of S, not less than 0.05% of P, the balance of iron, and unavoidable impurities.

Description

technical field [0001] The invention relates to the field of steel material processing, in particular to a heat-resistant steel for sintering machine grates. Background technique [0002] The sintering machine is the key equipment of iron and steel metallurgy, and the grate bar is the key wearing part of the sintering machine. Its working temperature changes periodically in the range of 100-1000°C; during the high-temperature sintering process, it bears the gravity of sintered ore, the high-speed impact and wear of the two airflows of powder gas, and the oxidation and corrosion of carbon monoxide, carbon dioxide, sulfur dioxide and water vapor in the atmosphere. ; During the unloading process, it bears the mechanical wear of the sinter; in addition, there are mechanical vibrations during the operation, mechanical impact during the cleaning process, etc. The combined effect of high temperature oxidation, corrosion, wear, impact and thermal fatigue causes the grate bar of the...

AI Technical Summary

Problems solved by technology

[0006] (1) Ordinary cast iron: low cost, poor overall performance, and is rarely used at present

(2) Heat-resistant cast iron: high brittleness, poor oxidation resistance, short service life, rarely used at present

(3) High chromium cast iron: good high temperature oxidation resistance, high hardness, good wear resistance, small thermal expansion coefficient, strong deformation resistance, but poor toughness

(4) Austenitic heat-resistant steel: good high-temperature oxidation resistance and high-temperature strength, high plasticity and toughness, but large expansion coefficient, poor deformation resistance and wear resistance, and high cost

(5) Ferritic heat-resistant steel: small expansion coefficient, good deformation resistance and oxidation resistance, but its high temperature performance still needs to be improved

[0007] With the improvement of sinter output and quality requirements, the increase of sinter thickness, the extension of sintering temperature and time, the properties of grate materials, especially high temperature oxidation resistance, high temperature strength, high temperature wear resistance and thermal fatigue resistance, etc. higher requirements, traditional materials have been difficult to meet the requirements