US2266762A - Welding - Google Patents

Description

Patented Dec. 23, 1941 WELDING Theopliil E. Jerabek, East Cleveland, Ohio, assignor to The Lincoln Electric Company, Cleveland, Ohio, a corporation oi Ohio No Drawing. Application March 9, 1939, Serial No. 260,744

8 Claims. (01. 219-8) This invention relates as indicated to welding and more particularly to the deposition in molten form of alloy compositions which contain substantial amounts of manganese.

In Patent No. 2,038,178 issued to Paul E. Jerabek on April 21, 1936, is explained in considerable detail the process of depositing manganese rich ferrous alloys and there is also pointed out many of the difllculties which arise in successfully carrying out such process.

As pointed out in said patent, it is customary to employ substantial amounts of nickel or cobalt or both in manganese rich deposits of this character in order that upon normal cooling the deposit will remain predominantly austenitic. There is also disclosed in said patent the use of substantial amounts of at least one element of the class consisting of tungsten, molybdenum and vanadium for the purpose of imparting to the deposit the characteristic of being able to achieve substantially maximum hardness by means of a minimum of cold work.

I have now discovered that deposits of the character referred to in the above-identified patent may be materially improved and the cost thereof substantially decreased by the employment of another alloying element in partial or entire substitution for either the nickel or cobalt or both.

It is a principal object of my invention therefore to provide a weld metal deposit which is an improvement over the prior art both from the standpoint of superiority as well as reduced cost.

Other objects of my invention will appear as the description proceeds.

My invention then, consists of the step hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain steps embodying the invention, such disclosed steps constituting, however, but one of the various ways in which the principle of my invention may be used.

Broadly stated, this invention comprises the discovery that in compositions of the character referred to in the above-identified prior Patent No. 2,038,178 superior results can be achieved and the deposit produced more economically by the entire or partial substitution of the nickel and/or cobalt by copper.

The following is a broad range of compositions for the weld metal deposit of my invention:

Carbon From about 0.50% to about 1.20% Manganese From about 7.00% to about 15.00% Silicon From about .20% to about 1.00% Nickel None to about 10.00% Cobalt None to about 10.00% Copper From about .10% to about 10.00%

at least one of the following elements in the proportions given:

Molybdenum From about .10% to about 2.00 Tungsten From about .10% to about 2.00 Vanadium From about .10% to about 1.00%

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

In view of the fact that the present invention comprises the whole or partial substitution of copper for either or both nickel and cobalt, the foregoing range of compositions may be explained as follows. The amount of copper specified when used without any nickel or cobalt is usually sufficient to produce an entirely satisfactory deposit which upon normal cooling is predominantly austenitic. For certain variations in the characteristics of the alloy it may be desirable to add minor amounts of either nickel or cobalt. When minor amounts of either or both nickel or cobalt are added the amount of copper present in the alloy can be correspondingly reduced.

The following table therefore gives the broad range of percentages within which the various elements may be present when only copper is used for the purpose of insuring that the deposit upon normal cooling is predominantly austenitic:

Carbon From about .50% to about 1.20% Manganese From about 7.00% to about 15.00% Silicon From about 0.20% to about 1.00% Copper From about .10% to about 10.00%

at least one of the following elements in the proportions given:

Molybdenum From about 0.10% to about 2.00 Vanadium From about 0.10% to about 1.00% Tungsten From about 0.10% to about 2.00%

Carbon From about 0.05% to about 1.20% Manganese--- From about 7.00% to about 15.00% Silicon From about 0.20% to about 1.00% Nickel From about 0.10% to about 10.00% Copper From about 0.10% to about 10.00%

at least one of the following elements in portions given:

Molybdenum--. From about 0.10% to about 2.00% Vanadium From about 0.10% to about 1.00% Tungsten From about 0.10% to about 2.00%

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

Now if only cobalt is employed in conjunction with copper in order to insure that the weld metal deposit upon cooling will be predominantly austenitic, the broad range of compositions will be substantially as follows:

Carbon From about 0.05% to about 1.20% Manganese From about 7.00% to about 15.00% Silicon From about 0.20% to about 1.00% Cobalt From about 0.10% to about 10.00% Copper From about 0.10% to about 10.00%

at least one of the following elements in the proportions given:

Molybdenum From about 0.10% to about 2.00 Vanadium From about 0.10% to about 1.00% Tungsten From about 0.10% to about 2.00%

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

A somewhat narrower range of percentages within which the various elements may be present in a weld metal deposit in accordance with my invention is as follows:

Carbon From about 0.50% to about 1.20% Manganese--- From about 9.00% to about 14.00% Silicon From about 0.35% to about 0.75% Nickel None to about 6.00% Cobalt None to about 6.00% Copper From about .10% to about 5.00%

at least one of the following elements in the proportions given:

Molybdenum.-. From about 0.10% to about 2.00% Vanadium From about 0.10% to about 1.00% Tungsten From about 0.10% to about 2.00%

metal deposit of the following composition:

Carbon From about 0.60% toabout 0.80% Manganese From about 10.00% to about 13.00% Silicon From about 0.25% to about 0.45% Nickel Not substantially in excess of .20% Cobalt Not substantially in excess of .20%v Copper From about .90% to about 1.25%

at least one of the following elements in the proportions given:

Molybdenum From about 0.35% to about 0.75% Vanadium From about 0.10% to about 0.75% Tungsten From about 0.35% to about 0.75%

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

It will be understood of course that the weld metal deposit having the above-identified composition may be laid down in any one of a number of conventional ways as by the use of a metallic electrode having an appropriate compo sition or by use of either a carbon are or a gas flame melting down a filler strip of appropriate composition.

I have found, however, that by the use of a metallic electrode of appropriate composition superior results are usually secured since by this process it is possible to lay down the weld metal without over-heating the base metal. Overheating the base metal is to be avoided both from the standpoint of a possible detrimental effect which such over-heating may have on the base metal, and furthermore, when the base metal is highly heated the rate at which the weld metal deposit cools is materially retarded thus accelcrating the rate of decomposition of the austenitic structure of the deposit.

When a filler strip or, as above indicated, preferably a metallic weld rod, is employed the composition thereof may, as is well known, be required to be slightly different than that of the desired weld metal. This is due to the fact that in laying down the metal by means of an electric are or the like certain of the constituents of the composition will be oxidized or otherwise removed from the composition.

When laying down a weld metal deposit having a composition within the preferred range of percentages set forth in the table last-above given and when employing a bare metallic weld rod for such purpose, which weld rod is melted down by-the arc to yield the desired composition; the weld rod will have a composition as follows:

Carbon From about 0.85% to about 0.92% Manganese From about 12.50% to about 13.50% Silicon From about 0.40% to about 0.60% Nickel Not substantially in excess of .20% Cobalt Not substantially in excess of .20% Copper From about .90% to about 1.25%

at least one of the following elements in the proportions given:

Molybdenum.-. From about 0.35% to about 0.75% Vanadium"--- From about 0.10% to about 0.75% Tungsten From about 0.35% to about 0.75%

,and the remainder being substantially iron together with such other alloying elements and impurities as are sometimes found in this general type of alloy composition. A weld rod having this composition is new per se.

It is further in the contemplation of my invention to provide the weld metal deposit by means of a metallic electrode consisting of a metal core and an adherent layer which contains the alloying constituents. Such layer may take the form of a uniform coating over the weld rod which may include other well known weld rod covering constituents, or the alloying elements may be included in a slot or other depression formed in the body of the metallic core. Copper powder, for example, may be advantageously included in the weld rod in either of these forms in order to supply the amount of copper specified in order that the weld metal deposit, upon cooling, will remain predominantly austenitic.

Throughout the foregoing description of my invention reference has been made to compositions which include at least one of the elements molybdenum, vanadium and tungsten for the purpose of imparting thereto increased hardness by means of a minimum of cold work. My invention is not to be limited, however, to compoazeeyea to about 1.20% to about 15.00% to about 10.00%

Carbon From about 0.50% Manganese From about 7.00% Copper From about 0.10%

the remainder being substantially all iron, together with such other alloying elements from the group consisting of nickel, cobalt, tungsten, molybdenum, vanadium, silicon, aluminum, phosphorus, sulfur, arsenic, tin, etc., as are either sometimes employed as alloying elements for the purposes for which these elements are commonly employed in the prior art in manganese-rich ferrous alloys or present as incidental inclusions or impurities. The generic invention may, therefore, be stated as being the inclusion of the specified amounts of copper for the purposes stated in a manganese-rich ferrous alloy which is laid down as a weld metal deposit as by means of the electric arc.

Throughout the foregoing description where the composition of the deposit weld metal has been given, only such elements as are important to the present invention have been referred to. While minor amounts of silicon have been specified, it is entirely possible to make a fairly satisfactoryj weld metal deposit in which silicon is commercially absent. 5

In certain of the claims, therefore, in defining the generic invention, it will be found unnecessary to include silicon, molybdenum, vanadium, or tungsten, as an essential constituent. It is to be understood, therefore, that throughout the foregoing description and in the appended claims, the term the remainder being substantially all iron" when used, is to include amounts of alloying elements and rimpurities such as tungsten, molybdenum, vanadium, aluminum, silicon, phosphorus, sulphur, arsenic, tin, etc., which are sometimes employed as additional alloying elements or found as impurities in compositions of the character described.

Since the preferred embodiment of my invention comprises the provision of a metallic electrode which when melted down will give a weld metal deposit of the specified composition, it will be found in ordering such weld rodcomposition from steel mills that many times additional alloying elements will be present in minor amounts by virtue of the fact that they are included inthe scrap metal from which the alloy is made by the steel mill. Minor amounts of such alloying elements as may be incidentally included and which are not incompatible with the principal alloying constituents specified will be found to be permissible in making up such weld rods.

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

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

1. An arc welding electrode which when melted by the arc will yield a weld metal deposit which upon normal cooling is predominantly austenitic and which comprises:

Carbon From about 0.50% to about 1.20% Manganese From about 7.00% to about 15.00%

- From the group comprising nickel and cobalt About 10.00%

Copper From about 0.10% to about 10.00%

said deposit having imparted thereto the char-'- acteristics of being able to achieve substantially maximum hardness by means of aminimum of cold work by the presence of at least one of the following additional elements in a substantial amount, not exceeding the percentage given:

Tungsten About 2.00% Molybdenum About 2.00% Vanadium About 1.00%

and the remainder being substantially all iron.

2. An arc welding electrode which when melted by the arc will yield a weld metal deposit which upon normal cooling is predominantly austenitic and which comprises:

Carbon From about 0.50% to about 1.20% Manganese-" From about 7.00% to about 15.00% Nickel About 10.00% Copper From about 0.10%to about 10.00%

Tungsten About 2.00 Molybdenum About 2.00 Vanadium About 1.00%

and the remainder being substantially all iron.

3. An arc welding electrode which when melted by the arc will yield a weld metal deposit which upon normal cooling is predominantly austenitic and which comprises:

Carbon From about 0.50% to about 1.20%

Manganese From about 7.00% to about 15.00% Copper From about 0.10% to about 10.00%

said deposit having imparted thereto the characteristics of being able to achieve substantially maximum hardness by means of a minimum of cold work by the presence of at least one of the following additional elements in a substantial amount, not exceeding the percentage given:

Tungsten About 2.00% Molybdenum About 2.00 Vanadium About 1.00%

and the remainder being substantially all iron. 4. An arc welding electrode which comprises:

and at least one of the following additional elements in a substantial amount, not exceeding the percentage given:

Tungsten About 0.75 Molybdenum About 0.75 Vanadium About 0.75

and the remainder being substantially all iron.

5. An arc welding electrode which when melted by the arc will yield a weld metal deposit which upon normal cooling is predominantly austenitic and which comprises:

Carbon From about 0.85% to about 0.92% Manganese From about 12.50% to about 13.50% Silicon From about 0.40% to about 0.60% Copper From about 0.90% to about 1.25%

and the remainder being substantially all iron.

6. A weld metal deposit which upon normal cooling is predominantly austenitic and which comprises:

Carbon--- From about 0.60%toabout 0.80%

Manganese From about 10.00% to about 13.00%

From the group comprising nickel and cobalt Not substantially in excess of about 0.20%

Copper From about 0.90% to about 1.25%

said deposit having imparted thereto the characteristics of being able to achieve substantially maximum hardness by means of a minimum of cold work by the presence of at least one of the following additional elements in a substantial amount, not exceeding the percentage given:

Tungsten About 0.75% Molybdenum About 0.75% Vanadium About 0.75%

and the remainder being substantially all iron.

7. A weld metal deposit which upon normal cooling is predominantly austenltic and which comprises:

Carbon From about 0.60% to about 0.80% Manganese From about 10.00% to about 13.00% Silicon From about 0.25% to about 0.45% Copper From about 0.90% to about 1.25%

said deposit having imparted thereto the characteristics of being able to achieve substantially maximum hardness by means of a minimum of cold work by the presence of at least one of the following additional elements in a substantial amount, not exceeding the percentage given: I

Tungsten From about 0.35% to about 0.75 Molybdenum From about 0.35% to about 0.75% Vanadium From about 0.10% to about 0.75%

and the remainder being substantially all iron.

8. A weld metal deposit which upon normal cooling is predominantly austenitic and which comprises:

Carbon From about 0.60% to about 0.80% Manganese From about 10.00% to about 13.00% Silicon From about 0.25% to about 0.45% Copper From about 0.90% to about 1.25% Molybdenum. From about 0.45% to about 0.65%

and the remainder being substantially all iron.

THEOPHIL E. JERABEK.