Steel for high-tenacity air cooling drill tool and production method thereof

Abstract

The invention discloses steel for high-tenacity air cooling drill tool and a production method thereof.The steel is prepared from, by weight, 0.1-0.40% of C, 0.7-1.3% of Si, 1.7-2.5% of Mn, 0.7-2.0% of Cr, 0.1-0.3% of Mo, 0.04-0.2% of V, 0.02-0.6% of Al, 0.001-0.08% of Sc, or 0.001-0.02% of other rare earth elements Ce and La, and the balance Fe, wherein Sc is from intermediate alloy of Al and Sc, and the weight percent of the Sc in the intermediate alloy is 1.5-4%.According to the steel, the tenacity and plasticity can be improved, the drilling tool and other components have the best toughness cooperation, the service fatigue life of the drilling tool is remarkably prolonged, and the steel is not likely to deform and low in cost.

Description

technical field

[0001] The invention relates to the technical field of materials, in particular to a high-strength toughness air-cooled drill steel and a production method of the high-strength toughness air-cooled drill steel. Background technique

[0002] Rock drilling tools are slender rods, and direct liquid quenching will easily lead to severe deformation and make them unusable. Therefore, heavy-duty drill rods are made of low-carbon alloy steel, and then carburized, air-cooled, quenched, and tempered at low temperature to reduce quenching deformation. Martensite is obtained in the surface carburized layer, and martensite plus bainite is obtained in the center as the final use structure. However, most of these steels currently use low-carbon Ni-Cr steels, which have the advantages of stable performance, excellent strength and toughness, low notch sensitivity, and gentle surface carbon concentration gradient after carburizing. However, a higher Ni content leads to a si...