US2198476A - Alloy compositions and articles made therefrom - Google Patents

Description

UNITED STATES PATENT OFFICE ALLOY COMPOSITIONS AND ARTICLES MADE THEREFROM No Drawing.

Application August 27, 1934, Serial No. 731.532. itenewed June 1, 1939 6 Claims.

This invention relates as indicated to alloy compositions and articles made therefrom. and relates more particularly to ferrous alloys of the type in which molybdenum and tungsten are important alloying elements.

In my prior Patent No. 1,937,334, dated November 28, 1933, there are disclosed alloy compositions of the class in which molybdenum and tungsten are principal alloying elements and in which molybdenum and tungsten bear to each other a certain defined proportional relationship. The present invention is, in efiect, an extension of the teaching in this prior patent, particularly with respect to variations in the carbon, manganese, silicon, vanadium and chromium percentages.

It is among the objects of my invention to provide alloy compositions of the same general character as those disclosed in my above identified prior patent but which, due to variations in the amounts of certain of the alloying elements used. are better suited for certain purposes than the compositions defined in such prior patent. Other objects of my invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends. said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The following description sets forth in detail some approved combinations of ingredients embodying my invention, such disclosed means constituting, however, but a few of the various forms in which the principle of the invention may be used.

My invention may be, as above indicated, stated in general terms as comprising the discovery that certain variations in the composition or compositions disclosed in my aforementioned prior patent result in alloys, particularly useful for certain purposes; more specifically the present invention relates to variations in the amounts of carbon, manganese, silicon, and chromium and to the omission of vanadium.

In accordance with my present invention, an alloy may contain the following elements within the percentages given, viz:

Per cent Carbon 0. 15 to 1. 60 Manganese None to 2.00 Silicon None to 3. O Chromium None to 15. 00 Tungsten 0. 20 to 6.00 Molybdenum 0. 60 to 15. 00 Cobalt None to 16.00

the remainder being substantially iron together with such other alloying elements and impurities as are sometimes found in this type of alloy compositions.

Specific examples of vanadium-free compositions are as follows, viz:

'l'genotes below 30%.

the remainder being substantially iron together with such other alloying elements and impurities as are sometimes found in this type of alloy compositions.

The importance of satisfactory alloy compositions in which vanadium is not an essential ingredient, is potentially great especially so as vanadium is an expensive element, which is only produced in small quantities in this country.

The above example is of particular interest, in that its raw material cost is very low. When hardened at 2250 F. and tempered at 1040 F. it showed a Rockwell hardness of C67 together with high strength. Cutting tools such as drills showed excellent performance.

The type of steel having a low carbon content and in which vanadium and cobalt are not essential for certain uses has a potential usefulness in the field of steels in which strength and toughness are of greater importance than cutting quality. It is particularly believed that the carbon content of about 0.35% will produce steels which with proper heat treatment will have excellent strength and fatigue-resisting properties. The variety having a carbon content of 0.15% is expected to show some increase in strength after appropriate heat treatment and is particularly suitable for use as a carburizing steel.

The type of steel having a carbon content below 0.30% will probably find a field of usefulness, principally in the structural steels, in which strength is a more important characteristic than cutting quality. The valuable possibility is also recognized of carburizing this type of steel so that it may have a strong and tough core together with a hard wear-resisting case.

As previously indicated, compositions of the general class disclosed herein are similar to the general class disclosed in my prior Patent No. 1,937,334 with respect to the tungsten and molybdenum content, i. e., the amount of tungsten in the compositions may be broadly stated as comprising about 5% to about 40% of the amount of molybdenum present. A somewhat narrower range of proportional relationships between tungsten and molybdenum contemplates the use of tungsten in amounts from 10% to 30% of the amount of molybendum present. The broad range of from 5% to 40%. above referred to. may be conveniently divided into the following groups, viz.: 5% to 16%. 16% to 25% and 25% to 40%.

Attention is directed to the fact that certain of the examples included in the foregoing description of my invention may be readily nitrlded.

As is well known to those familiar with the art, any specification for a particular alloy composition must permit of certain variations due to the fact that in making up the composition, it is extremely difiicult, if not impossible, to commercially produce a composition exactly like a given specification. It is to be understood. therefore, that throughout the description and claims where I have used figures to denote definite amounts and ranges, such amounts and ranges are to be construed to include the range of variations usually permissible in making up alloy compositions to given specifications.

It should be noted that where the term none" is used to denote the absence of a particular element, or where an alloy composition is indicated as being free" from any element. the construction to be placed upon these terms is a commercial absence of the elements in question. Silicon. manganese. chromium, vanadium and cobalt may be considered as commercially absent if they are present in amounts less than 0.05%.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the materials employed. provided the ingredients stated by any of the following claims or the equivalent of such stated ingredients be employed.

I, therefore. particularly point out and distinctly claim as my invention:

1. A vanadium-free ferrous alloy composition, comprising:

Carbon From about 0.30% to about 1.60% Silicon From a trace to about 3.00% Manganese From a trace to about 2.00 Chromium From a trace to about 15.007} Molybdenum" From about 0.60% to about Tungsten From about 5% to 40% of the amount of molybdenum presand the remainder being substantially all iron.

2. A vanadium-free ferrous alloy composition, comprising:

amount of molybdenum present and the remainder being substantially all iron.

3. A vanadium-free ferrous alloy composition, comprising:

Carbon From about 0.30% to about 1.60%

Silicon From a trace to about 3.00;

Manganese From a trace to about 2.00 T

Chromium From a trace to about 15.00%

Molybdenum From about 0.60% to about Tungsten From about 16% to 25% of the amount of molybdenum present and the remainder being substantially all iron.

4. A vanadium-free ferrous alloy composition. comprising:

Carbon About 0.35% Manganese From a trace to about 0.30% Silicon From a trace to about 0.30% Chromium About 1.00% Tungsten About 0.30% Molybdenum About 1.20%

and the remainder being substantially all iron.

5. A vanadium-free ferrous alloy composition,

comprising:

Carbon About 0.75% Manganese About 0.70% Silicon About 1.60% Chromium About 3.29% Tungsten About 1.59% Molybdenum About 7 23% and the remainder being substantially all iron.

6. A vanadium-free ferrous alloy composition,

comprising:

Carbon About 0.35% Manganese From a trace to about 0.30% Silicon From a trace to about 0.30% Chromium About 1.00% Tungsten About 0.15% Molybdenum About 0.60%

and the remainder being substantially all iron.

JOSEPH V. END/IONS.