US1521736A - Alloy - Google Patents

Description

Patented lain. 6, 1925.

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JOHN F, wannnnsnn; or HIGHLAND ranx, Ann Jean 1,. rtcomUD. OE-DEAKBQRN MICHIGAN, assrenons T0 roan MOTOR conraguy, or, nn'morcn, ivrrcrrrqau, A con- PORATI ON OF DELAWARE.

1i 0 Drawing.

To all whom it may concern:

Be it known that we, JOHN F. WANDER- and JOHN L. 'McCLoUD, citizens of the United States, residing, respectively, at Highland Park and Dearborn, in the county of Wayne and State of Michigan, have invented new and useful Improvements in Alloys, of which the following is aspecification.

The object of our invention is to provide an alloy of relatively slight cost which will have heat resisting qualities in a large deree. g A further object of our invention is to provide an alloy which is especially adapted to retain its structure and more especially its surface structure although subjected to repeated rapid changes of ten'iperature from atmospheric tei'nperature to many hundred degrees.

A further ob]ect of our invention is to provide an alloy which is readily formed and which will fulfill the requiren'ients for 'the valves for heavy duty,1nternal combus tion' engines.

Withthesc and other objects in. view ourv invention consists in the arrangement, construction andcombinatfonof the various found that we can combinerclatively small quantit es of chromium and silicon with a low. carbon steel to thereby form a valve alloy which has proven very satisfactory for use in a large number of tractor engines which are run continuously with a full load so that the valves used were subjected to the hardest possible type of test. We are aware that it has already been proposed to combine chromium and silicon with steel to form a heat resisting alloy for Valves but we have found that the alloys s0 proposed were very expensive on account of the large amounts, relatively, of silicon and chromium which were'introduced into the alloy and on account of the difficulty of properly admixing such a large proportion of these elements. ()ur experiments have shown that with the formula hereafter given we have produced an alloy which has a structural and surface ciency of the metal to resistheat. tions in the carbon content of considerable amounts do not affect the heat resisting ALLOY.

Application filed July 19, 1923. Serial No. 652,609.

.03% to 10%; sulphur, 04% to 10%.

This formula represents an average from a large number of analyses taken from a large number of different heats of our alloy and should be, therefore, considered reprev sentative. If the quantities of chromium or silicon .are materially increased above the amounts here specified, we have found that some proportions reduce the etli iency of the metal to resist heat and thatother proportions do not materially increase the efli- Variaqualitics of this metal and the same is substantially true in connection with the manganese content. If, however, the quantity of phosphorus is increased above .300 of-1% or of sulphur above .4-00 of 1% the quality becomesnoticeably poorer. If the silicon and chromium contents are reduced more than 1% .under those amounts given in this formula, then a decrease in the resistance of the metal to the act on of heating becomes very noticeable.

The principal advantage of our improved alloy rests in the fact that we are able to produce a material which is thoroughly adapted to use in valves for internal combustion engines which are subjected to high temperatures and that this alloy can be produced at a cost very materially less than that of any other alloy with the same heat resisting qualities that we have been able to discover. a

Some changes may be made in the proportions of the ingredients of our improved alloy and various methods may be used for securing the desired analysis. The use of this alloy is of course not limited to the valves but of course may be extended to any application where a metal is desPred which Will retain its structure and surface under continued high temperatures'and which also will withstand rapid Variations of temperature of many hundred degrees.

We claim as our invention:

1. An alloy with high heat resisting qualities having ferrous base combined with carbon from 25% to .45%; manganese, 25% to .45%; chromium, 1.85% to 2.50%; and silicon, 3.60% to 4.20%.

2. An alloy with high heat resisting qualitieshaving a ferrous base combined with carbon 25% to .4i5%; manganese, 25% to 45%; chromium, 1.85% to 2.50%; and silicon, 3.60 to 420%; and, neither more than 103% of Phosphorus nor over 04% of sulto 45%; chromium 1.85% to 2.50%; and

silicon, 3.60% to 4:20%, and not more than .50% of impurities.

4. Aheat resisting alloy having a low carto 3.50% of chromium and from 2.60% to 520% of silicon.

Dated July 5, 1923.

JOHN F. WANDERSEE. JOHN L. MCGLOUD.

bon ferrous base combined with from .85% I