US3692515A

US3692515A - Ferrous alloys and abrasion resistant articles thereof

Info

Publication number: US3692515A
Application number: US748631A
Authority: US
Inventors: Stewart G Fletcher; Walter T Haswell Jr
Original assignee: Latrobe Steel Co
Current assignee: Latrobe Steel Co
Priority date: 1968-07-30
Filing date: 1968-07-30
Publication date: 1972-09-19
Anticipated expiration: 1989-09-19

Abstract

AN ABRASION RESISTANT ALLOY STOCK MATERIAL CONSISTING ESSENTIALLY OF CARBON ABOUT 1% TO 4.25%, SAID CARBON BEING IN EXCESS OF THAT NECESSARY TO IMPART A DESIRED HARDENABILITY, SILICON ABOUT 1.5% MAXIMUM, MANGNESE ABOUT 1.5% MAXIMUM, CHROMIUM ABOUT 10% TO ABOUT 15%, MOLYBDENUM LESS THAN ABOUT 2% TITANIUM ABOUT 0.5% TO ABOUT 5%, TUNGSTEN LESS THAN ABOUT 3%, NICKEL LESS THAN ABOUT 3%, COBALT LESS THAN ABOUT 5%, VANADIUM LESS THAN ABOUT 5%, SULFUR UP TO ABOUT 0.25% AND THE BALANCE IRON WITH RESIDUAL IMPURITIES IN ORDINARY AMOUNTS, SAID TITANIUM BEING COMBINED WITH SAID EXCESS CARBON IN A WEIGHT RATIO OF 4:1 AND THE VANADIUM WITH CARBON IN A WEIGHT RATIO OF ABOUT 4.2 (V-1):1, SAID STOCK MATERIAL HAVING BEEN REDUCED BY WORKING AT LEAST ABOUT 5% IN CROSS-SECTION.

Description

United States Patent C US. Cl. 75126 A 7 Claims ABSTRACT OF THE DISCLOSURE An abrasion resistant alloy stock material consisting essentially of carbon about 1% to 4.25%, said carbon being in excess of that necessary to impart a desired hardenability, silicon about 1.5% maximum, manganese about 1.5% maximum, chromium about 10% to about 15%, molybdenum less than about 2%, titanium about 0.5% to about tungsten less than about 3%, nickel less than about 3%, cobalt less than about 5%, vanadium less than about 5%, sulfur up to about 0.25% and the bal ance iron with residual impurities in ordinary amounts, said titanium being combined with said excess carbon in a weight ratio of 4:1 and the vanadium with carbon in a weight ratio of about 4.2 (V1):l, said stock material having been reduced by working at least about 5% in cross-section.

This application is a continuation-in-part of our copending application Ser. No. 429,621 filed Feb. 1, 1965, now abandoned.

This invention relates to ferrous alloys and abrasion resistant articles thereof and particularly to a low cost abrasion resistant alloy which has been worked. The search for steels having high abrasion resistance and low cost, together with satisfactory workability, has been a long and continuing one. Examples of uses for such steels are brick mold liners, tile dies, sand blast equipment, shot blast equipment and various forms of dies. Alloys generally available at a favorable cost are undesirably shortlived and less than satisfactory for abrasion-resisting purposes.

We have discovered an alloy having improved forgeability, workability and abrasion resistance over any alloys previously available to the metallurgical industry. Our invention provides an abrasion-resistant alloy in which carbon within certain limits, is added in excess of that necessary to give a desired hardening ability to the alloy together with vanadium and titanium in certain proportions and within certain limits such that the excess carbon equals V-l Ti Considering only the essential elements of our alloy, the preferred analysis for most abrasion-resisting applica- Balance substantially iron with residual impurities in ordinary amounts, said titanium being combined with carbon in a weight ratio of 4:1.

The composition of our alloy may, however, extend Patented Sept. 19, 1972 ice over a relatively wide range and still retain its desirable properties of workability and abrasion-resistance. It may include alloying elements such as nickel, cobalt, tungsten and vanadium within certain limited amounts and proportions without detrimentally affecting the abrasion-resistance. Such wider range of composition may fall within the following limits:

Carbon About 1 to about 4.25%. Silicon About 1.5% maximum. Manganese Do.

Chromium About 10% to about 15%. Molybdenum Less than 2%.

Titanium About 0.5 to about 5%. Tungsten Less than 3%.

Nickel D0.

Cobalt Less than 5%. Vanadium Do.

Sulfur Up to 0.25%.

Balance substantially iron with residual impurities in ordinary amounts, said titanium being combined with carbon in a weight ratio of 4:1 and the vanadium with carbon in a weight ratio of 4.2 (Vl):1.

The expression less than followed by a percentage figure in this application, in the context of this application means that the particular element may be entirely absent or it may be present in an amount not to exceed the percentage concentration given. The presence of these elements is optional up to the amount specified in the ranges of composition given above.

The alloy is cast and preferably worked by forging, rolling or the like to reduce the cross section in an amount equal to at least about 5% of the original size. The alloy articles are preferably heat treated after working by tempering to achieve a desired tempered hardness. Tempering is-preferably carried out at temperatures in the range 900-950 F. after austenitizing at a temperature in the range l600-l950 F.

In order to illustrate the improved properties of our new alloy, several heats were made within the range of composition herein specified and compared with steels previously used for making brick liners and the like. The compositions appear in Table I. Each of the articles was formed by hammer forging to reduce the cross section about 40% and tempered at 900 F.

TABLE I Alloy C Cr W Mo Ti V Si Mn Ni Co Invention WR66 2.37 12.64 1.02 2.83 0.39 .47 Invention WRG Prior-art 2.4

Abrasion tests were made, comparing these several alloys with the results which appear in Table II.

Table II Alloy: Percent abrasion WR66 2.24 WR67 3.02 Prior art 3.76

While we have described and disclosed certain preferred embodiments of this invention, it will be understood that this invention may be otherwise embodied within the scope of the following claims.

We claim:

1. An abrasion resistant alloy stock material consisting essentially of carbon about 1% to 4.25%, said carbon being in excess of that necessary to give it a desired hardenability, silicon about 1.5% maximum, manganese about 1.5% maximum, chromium about 10% to about 15 molybdenum less than about 2%, titanium about 0.5% to about tungsten less than about 3%, nickel less than about 3%, cobalt less than about 5%, vanadium less than about 5 sulfur up to about 0.25% and the balance iron with residual impurities in ordinary amounts, said titanium and vanadium being combined with carbon in excess of that necessary to give a desired hardenability in proportions such that titanium is combined with a portion of said excess carbon in a Weight ratio of 4:1 and the vanadium with the balance of said excess carbon in a weight ratio of about 4.2 (V -4) :1, said stock material having been reduced by working at least about 5% in cross sectional area from its as cast condition.

2. A formed article made from a ferrous base metal comprising carbon about 1% to about 4.25%, silicon about 1.5% maximum, manganese about 1.5 maximum, chromium about to about molybdenum less than about 2%, titanium about 0.5% to about 5%, tungsten less than about 3%, nickel less than about 3%, cobalt less than about 5%, vanadium less about about. 5%, sulfur up to about 0.25% and the balance iron with residual impurities in ordinary amounts, said titanium and vanadium being combined with carbon in excess of that necessary to give a desired hardenability in proportions such that titanium is combined with a portion of said excess carbon in a weight ratio of 4:1 and the vanadium with the balance of said excess carbon in a weight ratio of 4.2 (V1):1, said alloy being characterized by workability, castability, abrasion resistance and high impact resistance and having been formed by working the base metal to reduce its cross section at least 5%.

3. A formed article of manufacture made from a terrous base metal alloy capable of being worked and cast to ultimate shape comprising carbon about 2.9%, silicon about 0.4%, manganese about 0.4%, chromium about 12.5%, molybdenum less than about 2%, titanium about 0.5% to about 5%, tungsten less than about 3%, nickel less than about 3%, cobalt less than about 5%, vanadium less than about 5 sulfur up to about 0.25% and the balance iron with residual impurities in ordinary amounts, said titanium being combined with carbon in a weight ratio of 4: 1, said alloy characterized by workability, castability, abrasion resistance and high resistance to impact, and having been formed by working the base metal to reduce its cross section at least 5% 4. A shot blast liner formed of an alloy consisting essentially of carbon about 1% to about 4.25%, silicon about 1.5 maximum, manganese about 1.5 maximum, chromium about 10% to about 15%, molybdenum less than about 2%, titanium about 0.5% to about 5%, tungsten less than about 3%, nickel less than about 3%, cobalt less than about 5 vanadium less than about 5%,

sulfur up to about 0.25% and the balance iron with residual impurities in ordinary amounts, said titanium" and vanadium being combined with carbon in excess of that necessary to give a desired hardenability in propertions such that titanium is combined with a portion'of said excess carbon in a weight ratio of 4.2 (V1):1 to titanium carbide and the vanadium with the balance of said excess carbon in a weight ratio of 4.2 (V1):l to form vanadium carbide, said alloy being characterized by workability, castability, abrasion resistance and high impact resistance and having been formed by working the base metal to reduce its cross section at least 5% in forming the liner.

sentially of carbon about 1% to about 4.25%, silicon about 1.5 maximum, manganese about 1.5% maximum, chromium about 10% to about 15 molybdenum less than about 2%, titanium about 0.5% to about 5%, tungsten less than about 3%, nickel less than about 3%, c0- balt less than about 5 vanadium less than about 5 sulfur up to about 0.25 and the balance iron with residul impurities in ordinary amounts, said titanium and vanadium being combined with carbon in excess of that necessary to give a desired hardenability in proportions such that titanium is combined with a portion of said excess carbon in a weight ratio of 4:1 to form titanium carbide and the vanadium with the balance of said excess carbon in a weight ratio of 4.2 (V-l) :1 to form vanadium carbide, said alloy being characterized by workability, castability, abrasion resistance and high impact resistance and having been formed by working the base metal to reduce its cross section at least 5% in forming the liner.

6. A brick mold liner formed of an alloy consisting essentially of carbon about 1% to about 4.25 silicon about 1.5 maximum, manganese about 1.5 maximum, chromium about 10% to about 15%, molybdenum less than about 2%, titanium about 0.5% to about 5 tungsten less than about 3%, nickel less than about 3 cobalt less than about 5%, vanadium less than about 5%, sulfur up to about 0.25 and the balance iron with residual impurities in ordinary amounts, said titanium and vanadium being combined with carbon in excess of that necessary to give a desired hardenability in proportions such that titanium is combined with a portion of said excess carbon in a weight ratio of 4:1 to form titanium carbide and the vanadium with the balance of said excess carbon in a weight ratio of 4.2 (V-1) :1 to form vanadium carbide, said alloy being characterized by workability, castability, abrasion resistance and high impact resistance and having been formed by working the base metal to reduce its cross section at least 5% in forming the liner.

7. A ceramic tile die formed of an alloy consisting essentially of carbon about 1% to about 4.25 silicon about 1.5 maximum, manganese about 1.5 maximum, chromium about 10% to about 15%, molybdenum less than about 2%, titanium about 0.5 to about 5%, tungsten less than about 3%, nickel less than about 3%, cobalt less than about 5%, vanadium less than about 5%, sulfur up to about 0.25 and the balance iron with residual impurities in ordinary amounts, said titanium and vanadium being combined with carbon in excess of that necessary to give a desired hardeuability in proportions such that titanium is combined with a portion of said excess carbon in a weight ratio of 4:1 to form titanium carbide and the vanadium with the balance of said excess carbon in a Weight ratio of 4.2 (V1):1 to form vanadium carbide, said alloy being characterized by workability, castability, abrasion resistance and high impact resistance and having been formed by working the base metal to reduce its cross section at least 5% in forming the liner.

References Cited UNITED STATES PATENTS 1,599,425 9/1926 McGuire 75126 2,147,121 2/ 1939 Emmons 75-126 2,575,218 11/1951 Giles 75126 3,231,709 1/1966 Folley 75126 X 3,295,401 1/1967 Rackoif 75126 X OTHER REFERENCES Tool Steels, 3rd ed., 1962, published by American Society for Metals, Metals Park, Ohio, pp. 699-704 and 718.

HYLAND BIZOT, Primary Examiner US. Cl. X.R.

75l26 C, 126 D, 126 E, 126 H, 128 B, 128 D, 128 T,

5. A sand blast liner formed of an alloy consisting es-128 V, 128 W UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,692 ,515 Dated September 19 1972 Inventor(5) Stewart G. Fletcher, et a1 a It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, claim 4, line 68, after "of" cancel "4.2 (V--1) :1 to" and insert 5 4:1 to form Column 4, claim 5, line 8, "residul" should read residual Signed and sealed this 2nd day of January 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR.

ROBERTYGOTTSCHALK Attesting Officer Commissioner of Patents FORM PO-lOSO (10-69) USCOMM-DC 6O376-P69 u.s, suvsnuucur PRINTING OFFICE 1 was 0-366-334.