High speed steel having high wear-resistance

Claim 2

A HIGH SPEED STEEL HAVING WEARRESISTANCE CONSISTING ESSENTIALLY OF 1.79 TO 4.78% BY WEIGHT CARBON, 5 TO 12% BY WEIGHT VANADIUM, 3 TO 10% BY WEIGHT NIOBIUM, AND THE BALANCE ESSENTIALLY IRON, WHEREIN SUBSTANTIALLY ALL OF VANDIUM AND NIOBIUM ARE PRESENT IN CARBIDE FORM, WHEREIN 0.2 TO 0.6% BY WEIGHT OF CARBON IS CONTAINED IN A FERROUS MATRIX, WHEREIN THE WEIGHT RATIO OF NIOBIUM TO VANADIUM (NB/V) IS FORM 0.6 TO 1, AND WHEREIN THE AREA RATIO OF THE CARBIDE PARTICLES IS 12 TO 30%.

Claim 3

A HIGH SPEED STEEL WHICH CONSISTS ESSENTIALLY OF 1.79 TO 4,78% BY WEIGHT CARBON, 5 TO 12% BY WEIGHT VANADIUM, 3 TO 10% BY WEIGHT NIOBIUM, AND AT LEAST ONE OF 2 TO 6% BY WEIGHT CHROMIUM, 1 TO 6% BY WEIGHT MOLYBDENUM AND 1 TO 6% BY WEIGHT TUNGSTEN, THE BALANCE BEING ESSENTIALLY IRON, WHEREIN SUBSTANTIALLY ALL OF THE VANADIUM AND NIOBIUM ARE IN CARBIDE FORM, WHEREIN 0.2 TO 0.6% BY WEIGHT OF CARBON IS CONTAINED IN A FERROUS MATRIX, WHEREIN THE WEIGHT RATIO OF NIOBIUM TO VANADIUM (NB/V) IS FROM 0.6 TO 1, AND WHEREIN THE AREA RATIO OF THE CARBIDE PARTICLES IS 12 TO 30%.

Claim 4

A HIGH SPEED STEEL WHICH CONSISTS ESSENTIALLY OF 1.79 TO 4,78% BY WEIGHT CARBON, 5 TO 12% BY WEIGHT VANADIUM, 3 TO 10% BY WEIGHT NIOBIUM, AND AT LEAST ONE OF 2 TO 6% BY WEIGHT CHROMIUM, 1 TO 6% BY WEIGHT MOLYBDENUM AND 1 TO 6% BY WEIGHT TUNGSTEN, THE BALANCE BEING ESSENTIALLY IRON, WHEREIN SUBSTANTIALLY ALL OF THE VANADIUM AND NIOBIUM ARE IN CARBIDE FORM, WHEREIN 0.2 TO 0.6% BY WEIGHT OF CARBON IS CONTAINED IN A FERROUS MATRIX, WHEREIN THE WEIGHT RATIO OF NIOBIUM TO VANADIUM (NB/V) IS FROM 0.6 TO 1, AND WHEREIN THE AREA RATIO OF THE CARBIDE PARTICLES IS 12 TO 30%.

Claim 5

A high speed steel according to claim 2, wherein said high speed steel contains 2 to 6% by weight chromium, 1 to 6% by weight molybdenum and 1 to 6% by weight tungsten.

Claim 6

A high speed steel consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and at least one of 2 to 6% by weight chromium, 1 to 6% by weight molybdenum and 10 to 6% by weight tungsten, the balance being essentially iron, wherein substantially all of the vanadium and niobium are in carbide form, wherein 0.2 to 0.6% by weight carbon is contained in the ferrous matrix, wherein the weight ratio of niobium to vanadium (Nb/V) is from 0.6 to 1, and wherein the area ratio of the carbide particles is 12 to 30%.

Claim 7

A high speed steel consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and at least one of 2 to 6% by weight chromium, 1 to 6% by weight molybdenum and 10 to 6% by weight tungsten, the balance being essentially iron, wherein substantially all of the vanadium and niobium are in carbide form, wherein 0.2 to 0.6% by weight carbon is contained in the ferrous matrix, wherein the weight ratio of niobium to vanadium (Nb/V) is from 0.6 to 1, and wherein the area ratio of the carbide particles is 12 to 30%.

Claim 8

A high speed steel according to claim 4, wherein said steel contains 2 to 6% by weight chromium, 1 to 6% by weight molybdenum and 1 to 6% by weight tungsten.

Claim 9

A high speed steel consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and at least one of up to 2% by weight nickel, 2 to 6% by weight chromium, 1 to 6% by weight molybdenum, and 1 to 6% by weight tungsten, the balance being essentially iron, wherein all of the vanadium and niobium are in carbide form, wherein 0.2 to 0.6% by weight carbon is contained in a ferrous matrix, wherein the weight ratio of niobium to vanadium (Nb/V) is from 0.6 to 1, and wherein the area ratio of the carbide particles is 12 to 30%.

Claim 10

A high speed steel consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and at least one of up to 2% by weight nickel, 2 to 6% by weight chromium, 1 to 6% by weight molybdenum, and 1 to 6% by weight tungsten, the balance being essentially iron, wherein all of the vanadium and niobium are in carbide form, wherein 0.2 to 0.6% by weight carbon is contained in a ferrous matrix, wherein the weight ratio of niobium to vanadium (Nb/V) is from 0.6 to 1, and wherein the area ratio of the carbide particles is 12 to 30%.

Claim 11

A high speed steel according to claim 6, wherein said steel contains 2 to 6% by weight chromium, 1 to 6% by weight molybdenum and 1 to 6% by weight tungsten.

Claim 12

A high speed steel having high wear resistance consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and at least one of 2 to 6% by weight chromium, 1 to 6% by weight molybdenum, 1 to 6% by weight tungsten, up to 2% by weight nickel and up to 10% by weight cobalt, the balance being essentially iron, said high speed steel composed of a ferrous matrix having 0.2 to 0.6% by weight combined carbon therein and carbide particles substantially uniformly distributed throughout the body of said high speed steel, substantially all of the vanadium and niobium in said high speed steel being in the form of primary carbide crystals, the weight ratio of niobium of vanadium (Nb/V) in said steel being 0.6 to 1 and the area ratio of the carbide particles in said steel being 12 to 30%.

Claim 13

A high speed steel having high wear resistance consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and at least one of 2 to 6% by weight chromium, 1 to 6% by weight molybdenum, 1 to 6% by weight tungsten, up to 2% by weight nickel and up to 10% by weight cobalt, the balance being essentially iron, said high speed steel composed of a ferrous matrix having 0.2 to 0.6% by weight combined carbon therein and carbide particles substantially uniformly distributed throughout the body of said high speed steel, substantially all of the vanadium and niobium in said high speed steel being in the form of primary carbide crystals, the weight ratio of niobium of vanadium (Nb/V) in said steel being 0.6 to 1 and the area ratio of the carbide particles in said steel being 12 to 30%.

Claim 14

A high speed steel according to claim 8, wherein said steel contains 2 to 6% by weight chromium, 1 to 6% by weight molybdenum and 1 to 6% by weight tungsten.

Claim 15

The high speed steel of claim 8, wherein said carbide particles contain both vanadium and niobium.

Claim 16

The high speed steel of claim 10, wherein said carbide particles are composed of a mixture of niobium carbide and vanadium carbide, a portion of said carbiDe particles containing predominantly niobium carbide, and another portion of said carbide particles containing predominantly vanadium carbide.

Claim 17

The high speed steel of claim 8, containing 7 to 12% vanadium.

Claim 18

The high speed steel of claim 8, wherein the carbide area ratio of the steel is greater than 20%.

Claim 19

The high speed steel of claim 8, having sufficient wear resistance such that the wear on a test piece 18 mm in diameter under a load of 800 g against an emery paper adhered to a 20 cm diameter turntable rotating at a rate of 600 rpm for 140 seconds in less than 0.02g.

Claim 20

The high speed steel of claim 14, wherein the wear resistance of the steel is such that the amount of wear is about 0.01g or less.

Claim 21

A high speed steel consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and the balance essentially iron, wherein substantially all of the vanadium and niobium are in carbide form, wherein 0.2 to 0.6% by weight carbon is contained in the ferrous matrix, wherein the weight ratio of niobium to vanadium (Nb/V) is from 0.6 to 1, and wherein the area ratio of the carbide particles is 12 to 30%.

Claim 22

A high speed steel consisting essentially of 1.79 to 4.78% by weight carbon, 5 to 12% by weight vanadium, 3 to 10% by weight niobium, up to 2% by weight silicon, up to 2% by weight manganese, and the balance essentially iron, wherein substantially all of the vanadium and niobium are in carbide form, wherein 0.2 to 0.6% by weight carbon is contained in the ferrous matrix, wherein the weight ratio of niobium to vanadium (Nb/V) is from 0.6 to 1, and wherein the area ratio of the carbide particles is 12 to 30%.

Claim 23

A high speed steel according to claim 16, wherein substantially all of the vanadium and niobium in said high speed steel are in the form of primary carbide crystals.

Claim 24

A high speed steel according to claim 17, wherein said carbide particles contain both vanadium and niobium.

Claim 25

A high speed steel according to claim 17, containing 7 to 12% vanadium.