US2125680A - Alloy - Google Patents

Description

Aug. 2, 1938. A, R, MacGREGOR 2,125,680

ALLOY Filed Julie 1o, 1936 0 .|25V .10l .76 1.0 l 1.5 v 8.0 .15 y

y (Ittorneg Patented ug. V2 1938 STATES 1 claim. (ci. sti- 154) My invention relates to copper base alloys suitable for use in welding, brazlng, and soldering, and relates particularly to ternary alloys of copper, phosphorus, and' tin adapted to be used for 5 such purposes.

An vobject of my invention isA to provide an improved alloy i'or the purposes s et forth hereinabove.

A second object oi.' my invention is to: provide y copper-phosphorus alloys having improved physical properties.

' Another object of my invention is to provide animproved alloycontaining copper and phosphorus, and adapted to use in welding, brazing,

l5 filling, and similar processes.

My invention has for other objects such other advantages as are found to obtain in the alloys' described and claimed herewith. It is well known that eutectic alloys generally have a relatively highl degree of iiuidity at temperatures above their melting points. Eutectlc alloys oi copper and phosphorus, i'or'exsmpla exhibit thlscharacteristic to a marked degree,`

and such alloys have been used in the past for brazlng, welding, and similar purposes. However, it has been found that the brlttleness and low duetllity oi these alloys makes them unsatisiactory whenvductile welds are desirable.

Izllave found that thel addition oi tin in the vunusual ductility and softness.' More specifi cally, I have found that alloys comprising copper,

phosphorus, and tin, in which the percentage oi phosphorus is less than or does not materially exceed that 1u the outeouo composition (obout'aa per cent) and containingtin in amounts les than l per cent, are very satisfactory for use -as weld- 40 ing* or braaing media. These in a application. andiorm a weld or illling having vunusually high d'uctility and softness, which al'- lows them to be` readily peened, machined, or

otherwise dressed in the weld. or elsewhere. Hy alloys, furthermore, produce a strong, dense weld or braze capable o! resisting high pressures, both gaseous and liquid. 'As stated hereinabove, my preferred alloysmi 5o coppenphosphorus; ansiv tin contain not more than about 8.3'per eentphosphorua'and'l have l found that a phosphorous content o i about 6.5 to 7.5 per cent is especially desirable for general use m suitable proportions in oooordsuoeyitnmy'mvention is also advantageous withfeopper Ialloys,

containinghighe'r and lowerpercentages o! phosphorus. however, and 'I have" found that especially.

' -ductile welds are obtained' by :the use `ofE an f phorus. With alloysof this'type having a phosphorous content ranging up toabout 8.3 per cent, I have found that the most eiiective tin addition is about 0.5 per cent, and that in substantially all Veases the maximum ductiJity-is obtained bythe 5 addition of this amount oi tin. Good results are also obtained by the addition of tin .in amounts from about 0.25 per cent to about 0.75 percent, but additions of tin in amounts less than about 0.2

` per cent or more than about 0.85 per cent have relatively little eieet on the ductility oi the alloys as compared with additions within my preferred range. In fact, larger additionsl o! tin may result in alloys having greater hardness land lower ductility than alloys of similar phosphorous 15 content to which no tin is added, as shown here- .inbelova l The veffect oi tin on phosphorus-copper alloys is illustrated in the following tables, which give the Brinell hardness values oi alloys, containing 20 constant phosphorous\ proportions, as stated. varying amounts oi tin, as stated, and the remainder` substantially copper;

Time. i 25 ggg-gi itlslent Brlnell rus ,um

to 0.5 a0 to 1.o 10o 4.o 1.o to ao m 4.0 as v 35 Table II :gg reagent nanou 1 o 0 .100 7.o 0.25 :a0 1.0 0.50 110 1.0 0.15 1an 1.o 1.00 1an 7.0 2.00 14a 45 1.0 aso los Table III Perce t 50 15 pungent hernan as VAo 21o as 0.25 son s.: 0.a0 11s 55' s.: 0. '1s m4' as 1.00 an 8.a 100 ma -rho uovo moet 'ure plottedlu m. 1 or the accompanyingdrawing. results on are obtained when other percentages o! phosphorus within the preferred range (from about 2 per cent to about 8.3 per cent) are used.

In addition to their improved ductility, I have also found that alloys of my preferred compositions have melting polnts considerably lower than that of the eutectic copper-phosphorus alloy, and are therefore more readily employabie for welding, brazing, soldering, llins, and the like. For example. I have found that the ternary alloy containing 'l per cent phosphorus and 0.5 per cent tin with the remainder substantially copper begins to melt at approximately 631 centigrade, with pronounced periods of arrest in the cooling curve at approximately 634, 663, and 709, being entirely liquid at about 885 centlgrade, as shown in Fig. 2.

I have successfully used alloys described hereinabove for welding and brazing ferrous and non-ferrous parts by both they electric arc and the gas llame methods, for joining brass, bronze, and copper tubes and sheets, and for the repair and liing of cast objects, both copper base and iron base. However, due to the unique properties of these alloys they are adapted to many uses, and it is not my intention to limit their application to any particular form or to any particular purpose., The alloys 4 constitutingl my present inventio may be prepared by processes analogous to those known to fthe art for the manufacture of other alloys. For example, I may melt phosphor-copper or a mixture of phosphor-copper 'and copper having the desired phosphorus content with the correct amount of tin, or I may melt the tin and cop per together and then add the phosphorus. The resulting alloy in either case is then cast, drawn. rolled, or otherwise fabricated, into welding rods, electrodes, or other desired forms. Itis generally more convenient to employ the alloy in such forms, but in any case a remarkably strong.

dense. ductile weld is formed by the use of my alannoso loys because of their fluidity, ductility, searching power, and strong adhesion to other metals.

I am aware that alloys of copper and phosphorus are known to the prior art as welding and brazlng media. as disclosed, for example, in U. S. Patents 1,652,107 to Eschhoiz and 1,651,709 to Jones. I am also aware that ternary alloys of copper, phosphorus, and tin have been developed in the past, and such alloys, which are generally of the type known as phosphor-bronzes, have many uses. 'Ihey have been used for welding, but do not produce-the results obtained with alloys of my preferred composition because of their generally higher tin content and lower phosphorus content. Similarly, my alloys are distinguished from those disclosed in U. S. Patent '1,988,422 to Miller by their characteristically lower tin contents, which produce materially different results as shown hereinabove.

When welding with alloys of my preferred oomposition, some of the phosphorus is driven out and serves ss an efficient deoxidizer, but enough remains to make the weld strong. The tin in the amounts specified overcomes the brittleness which would otherwise result from the presence of phosphorus, and makes it possible to peen or machine the weld, and the presence of tin in combination with the phosphorus makes tinning of

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