US2376210A - Alloy suitable for use as a bearing - Google Patents

Description

. in bearing alloys which.

, objects will appear hereinafter.

carrying contains eflective quantities of lead,

. than the quantity may be present" materially 'alloy in the as-cast condition has a Patented Mi, 15, i945 UNITED sTA'r-Es PATENT. omen I ALLOY sUlTAlilil xlfgsE As ABEARING Irvin: R. Valentine,

Electric company,

Erie, Pa., assignor to General I a corporation of New York 6 Claims. (01. 75-100) The present inventionis'an alloy and more cularly an alloy suitable for use as a bear-- ing. Bearing linings, among other qualifications, must have sui'ilcient hardness to resist effectively deformation due to pounding. A Brinell hardness of about-64:5 is satisfactory and is obtained employ a relatively large percentage of tin and a smaller percentageiof It is an object of the present invention to provide an alloy which is suitable for use as a'bearing and which contains neither tin nor zinc. It is a'further object of the present invention to provide an 'eilicient bearing alloy which has asuitable degree of hardness and'which does not cause scoring or welding in the bearing. other In my invention into effect, I employan alloy which consistsprincipally of copper but silicon and arsenic. The lead content of the alloy provides some lubrication but its principal use is to reduce the'quantity of copper employed. The quantity orlead in the alloy varies from a few percent up to about 15% by weight of the alloy. A lead content materially greater than 15% cause sweating of the casting.- A preferred range of lead content in the alloy varies from about 10 to about 14%.

The silicon content of the alloy varies from and provides the necessary degree of in the alloy. The silicon has a.

, hardness, elongation,

- ganese bronzes when run a slight softening takes place in the alloy.

vsilicon bronzes, aluminum bronaes and. man- 2% and the ratio of arsenictosilicoh is above .80,

a high temperature rise in about one minute at apressure of 300 pounds per square inch and in that period of time weld to the soft steel cylinder or score it badly. though roperwhen tested as a bearing material. hLv improved bearing alloy containing, arsenic and silicon not only has desirable physical properties but superior qualities as bearing materisll. For example, various alloy compositions consisting of copper, lead,

a silicon and arsenic, as hereinbefore set forth, were not give any machined to give a bearing square inches and were run dry on surface of three .a oft steel indication of welding or scoring. Applicants preferred alloy composition consist ing of about 12.5%- lead, 2.6% silicon, 1.45% arsenic with the remainder copper, in the as-castcondition, when operated five minutes showed a The properties maximum temperature of only 230 C. The same a maximum-temperature of 218 C.

of the alloy under ditions are improved by heat treatment for about tendency to increase the friction of the bearing but this effect is overcome by the presence of arsenic. .The arsenic not only overcomes the friction effect of the silicon buteliminates any scoring or welding out A preferred about 12.5% lead, 2.6% silicon, 1.45% arsenic with the balance substantially all copper. This impairing the properties of the strength of 33,330 pounds per square point of about 18,850 pounds per square inch, elongation of 8% in two inches and a hardness of 11.7. After heat treatment at 500' C.

inch, a yield an for six hours 'the following properties are ob- Tensile strength-pounds per square Yield point Elongation. -.per centin two inches inch; 36,220

'Brlnell hardness 'zsn.

" Whenthcarsenioand idiocau-eeaobabove to"2%%. A fraction of a" in the alloy as an. imp h-- b aring composition consists of spect to the temperature under operating conditions. However, when thefour to sixv hours at about 400 to about 700." c. n the ratio of arsenic to silicon'is within the range of .53 to so the heat treatment has advantages, particularly with redeveloped in the bearing ratio of arsenic to silicon is materially'less than ties in the as-cast condition. A heat-treatment 5 treated condition. ness of 4 the alloy for about six hours at about 400 ,0. provides entirely satisfactory results. Heating at higher as a rule does not materially im-Y; prove the properties of the alloy.

' If desired, manganese may be employed intbe ,alloy'although its presence does not result in any outstanding im vement in the alloy. If a small quantity is. employed, for example about 35% the alloy. has satisfactory pro erties 'but'a tendency soft in the as-oastf and host- If larger-quantities are employed,for example up to about 3.15%, hardto be somewhat is satisfactory and hardness of alloy in .the as-cast" The properties of the alloy. insensrsl. improved by-tbeuse-of mangmcla condition.

dry in bearing tests give con-' temperatures varying from materially greater than the bearing alloy has more satisfactory temperature properin the heat treated condition, considerably greater than the.

What I shim as new :md desire to secure by Patent @i' the Unit-e01 Emma, is:

1. An @130 a few per cent but met mare them 15%iead aswu 1.5 m 3% ailioon, @mut 1% b0 2%76 anemia with the remainder subsbantmlly all supper,

2. beaming allay a few par cent m afiwut 15% lead, abuut 1.5 m 3% silicon a 33mm 1 a: 2%% amsezziim with the remainder sub- 3. A beefing @RH mmamiaig & fiew per cent up mam 15% Head, mm; M; m 3% 5mm,

the 325mg? has them the qmmtiw a? m 4a A hearing aimy cents a iewpez" eem'i,

and up to abaut 15% lemi, abaw: 1.5 to 3% [about 1 2 V arsenic mm the remainder sub stantially all! copper, 22m ratio 02 the amenic the silicon being mthm the range $3.53 ta 5. An alloy containing about 12.4fi% lead, 2.13% 81110920., ambit {1.415% arsenic with the A e mainder subatzzmially an empzaer.

6. A hearing alloy cexatspimng'eubout 163 m 15% lead, about 1.5 to 3% 5333mm, abam 1 t0 2 /293; arsenic with the rmainder substantially aim 003% per.

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