Feinmetall Exhibit 2005
`FormFactor, Inc. v. Feinmetall, GmbH
`IPR2019-00082
`
`Page 1 of 13
`
`

`

`Elektrische
`
`Kontakte
`
`Von
`
`Ragnar Helm
`Dr. phil.
`
`Dritte vfiliig neubearheitete Auflagiz
`des But-hes V0.11 11.1-101111, Die technisclle Physik
`dcr clcktrisuhen Kuntaktc
`
`l 9 5 8
`
`umer lfiturbcit von E136 Helm Dr. phi}.
`heide SLMuIys {Pa.)
`
`Mi! 1 94 Abhiidnu g e n
`
`In engiiacher Sprnehc
`
`Springer-Verlag
`
`Berlin I Gettingen j Heidelberg
`
`Page 2 of 13
`
`

`

`Electric Contacts
`
`Handbook
`
`15?
`
`
`
`Tllipd compfctcly rewritten edition
`of “Die technischc Physik der elektrischnn Knmaktc"
`by R. I'Iolm
`
`195 8 -
`
`Ragnar Hoim
`
`Ph. D.
`
`aided by Else I‘IOlm PILD.
`both of SLMaIys (Pen)
`
`WiIlI 19,-] Figures
`
`Springer-Verlag
`Berlin / Gfittifigen f Heidelberg
`
`Page 3 of 13
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`

`

`
`
`Alle Rechte, insbaaomlcro das dor chrsctzung 1n frcmdc Sprachen. vorbehalten
`Ohne aumlrflckliehe Genehmlgung deg Verlagea ist 0.5 such nicht gestnttet,
`dimes Buch Oder Toilc dawns an! photomechanischem Wei—fie
`(PthDkODifi, Milnokopic) m1 vowiclfflltigen
`© by springer‘Feflun DEG.. BurflnfGfittingenIHcEchbem 1.958
`hinted. in Germany
`
`AUBURN UNIVERSITY. ALABAMA 3584’s
`
`Die Wiadargarbe van Gebrauchanamen, Handclsnnmcn, Wmenbezei'chnungen usw.
`in diflicm Buche berncht-igi a-uch ohnc heaondcrc Kcnnmeichnung nicht zuder An-
`nallmc, dnfi solche Namen {m Sinus der Warmmeichen- und Marmenschutz‘fleactz-
`ge‘bungalsfml zu betmuhten wirenuud daher vonjcdcrmwn benutztwerden dfim‘tcn
`
`AUBURN UNIVERSITY
`RALPH BRowN DRAUGHUN LPBRARY
`
`Page 4 of 13
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`

`

`Contents
`
`Page
`
`List ul' tine most. frequently used symbols and alibmviations ...... . ....... XVI
`
`Part I
`
`Stationary Bantams
`
`materialHr...
`
`contacts
`§ L Introduction. A aimpiifiéd aunmary of the “them-y of stationary Electric
`§2. The contact. surface .
`.
`.
`. 1......“
`__-.-....._..
`§3. The contuntresistance. Genmltheoqw
`§4. Calculabion of eonstrietion mgistanfios with constant rnsistivihy ....... .
`Problem A. '11. .d'Pi-oblem B”. 15. —I_Pmb]em G. Elliptic: 113901.. 15. —-I’r:o‘
`111010.13.” Circularaopofn 115. — Problem E. 18. —Problem F. The {11111181100
`01' the elliptio ahape of tho contact. area on the constriction msiutmwn
`swam-{1'11}; a. shape factor. 18.
`§5. (Joust-fiction resistances when conditions deviate from those in E4, but-
`with 13 still being a. constant. .....................................
`Problem A. Spreading mflstanoe. 2|]. — Problem B. Consimiution
`1203131911136 when the 11-3901. 15 covered with a film. 21. — Problem 0.
`Metallic contact with many 11-31mm. 22. —Problem D. The constriction
`resistance R(_1~,--a, l) of a. coherent contact area with .111 trimming. apot-s.
`24:. — Problem E. Distorted eons'tficfion. 24.
`§Ei Thermal constriction 1133131111103
`. ... .
`.
`. ...... .................. ..
`§7. Films on contacts.
`A Different typoa ocf 151113.21-—B A3111?!“of001111311;on 3L. — C. Tunnel
`mmmnm-of contagfi {331115.32
`§3 The contact mince as-n. functmn of 1111111 and 5111131113 115- well as plastic
`propeitieg of.the mombom
`In—
`A. Elastic. deformation, 33 — BPia-«113:; doformntlon 34. — L.
`fl'u'en‘c'e of tempermum and contact duration on the Contact Bl‘l'iflg 3T
`§9 Thexelation between 11:ontunf.londand refiintame, ‘pjartied'éiriy 3.13moderate
`and high load .. .
`. .......................
`A. Introduotidn with (31930111501011 of Egg. (9. 0:1) 39 - B Crossed rod
`contacts. 4:2. — C'. Explanation of this. ilanhad lilies in Fig.(901)
`44. 7 D Diversified measurements. 45. - E-. Uses: of diagram (901)
`in proiitiaua. 413. a I". Contact preloaded. with a high P. 47.
`§ 10. Contact resistunee 'un {mainly cleaned; mn'tmnt' very small contncl. loads
`§ 11. Tho Euriuomngqa of u. cmrentnouaimietiom Skin eifoctl .................
`A. inductanno. 52. -'.B.The skin éfi'r‘nt. 5:1.
`§1EL Electrodynamik: repulsion in a symmetric contact of a nun-magnetic
`
`.
`
`. .
`
`Page 5 of 13
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`56
`
`.59
`
`55
`70
`
`T5
`78
`
`S5
`
`87
`
`90
`
`95
`
`116
`
`Contents
`
`§ 13.
`
`§ 14.
`§ 15,
`
`§ 18.
`
`§ 17.
`§1s.
`
`The capacitance of a. contact. Electrostatic attraction in a. contact .....
`Example A. Crossed Tod contacts.
`[‘37. -Exs.m_plo B. Quaeiflot conututs.
`53. —- Example C. JOHNSON‘RABBEK. effect. 58.
`Measurement of the lion] bearing contact area. ......................
`The relationship between electric potential and temperature in a current
`constriction which is symmetric with respect
`to the contact surface;
`that. is, the (ti—19 relation
`The era—a9 relation in cases of dissynimotry ..........................
`Case A. Dissymme‘try in regions of the constriction which are distontfrom
`the cont-net. 7|). — Case R. Contact between highly diifemnt materials.
`71. — Case C. Contact between moderately different motels. 72. —
`Case D. Heat enters across AG. 72. — CaeeE. THOMSON effect is present.
`73. — Case .11". The qu—t‘ relation in the environment of a. bimetallic
`contact. 75.
`. ............................... .......
`KOELEII effect ........... .
`The influence of the Junior. heat on constriction lEfilahkhIlI’JC.
`.
`.
`Example A.Wrsnnnnxn-F1uwz-Luennz low"is valid. 80 — Example B.
`Semi--ecndneting material. 82. - Example C Heat flowmg across A.
`82.—- Example D. Independent of whether Winnmnam-FRANZ-Lonmrz
`law is valid. 84.
`
`§ 19.
`
`§ 20.
`
`Distribution ct'tl'le temperature in a. symmetric constriction with circular
`contact surface at given current . .................................
`Example A. 9 and l: are constant. 85. — Example B. Corresponding to
`Example A in §18. 86. — Example 0. Corresponding to Example B
`in § 18. Eli.
`Temperature distribution in the constriction of (I contact with circular
`contact surface and members with very dlfi’erent conductivities .......
`Example A. 88. — Example B. 89.
`§21.'
`Reeistonce — voltage characteristics of clean symmetric contacts. Soften-
`ing and melting collages .........................................
`Development of the temperature in a. current constriction .........
`.
`A. Introduction. 95. — B. Remarks concerning the diagram. 98. 7
`C. Moving contact. 101. i 1). Temperature development in a cylinder.
`103. — E. Cooling of s. previously heated contact region. 104. —
`F. Examples. 104.
`. ...................... .
`.
`.
`.
`The growth 0F tarnish fihm on motels
`A. Fundamentals of the theory. 105. — B. Poeeivol-Ing films. 110. 7
`O. TMnjching 01" various base content materials. 110. ._ D. Tar-Making
`of noble metals. 11.5.
`
`§22.
`
`§23.
`
`§24.
`
`§25
`§25
`
`. ............................
`.
`Water films, local cells and rusting .
`A. Tl-Liolmess of water films. 116. — Eliminating by means of electro-
`chemical atteclc. Local cells. 117.
`Thermoelectric efl'ecte ......... .......... ..................... .. _
`Observations on the tunnel effect
`. .
`.
`.
`.
`'
`.
`A. Introduction Method.121.— B. Observations givinga. lZSU -
`Cl. Measured 0' compared with the theoretical volue.127 —— B. Super
`conductivity of cont-nets. 128.
`
`.
`_
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`Page 6 of 13
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`Page 6 of 13
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`

`21’.
`
`Cont-en ta
`
`. 1.30
`§21E11L1111g 011511111511 11.111111
`A. Introductiun.130. —13. 11411112113. (191151-51 appefiflxfie of 1.111:
`process. 131. —C Camt-iunvoltflgeof flitting. 132— D. The £1511. bridges
`131'. — E. 15.-1'1'ltl.ing. 139. "I". The 11011131131". 14:1. —- G. Defii‘lsfing. 141. ~—
`H. 121111111 stage of flitting. 141.. — 1. Recent. investigafiwa of tiitidng.
`142.
`
`. . ....
`
`§2_.8 RUicimractmistice of 1211111111115 with'tlzu'u uJienfilma . .. .......... ... . .
`§29.Ad1m:11nm1'1111ry 1301112515155 whinh 5.121: 11111: heatnd to any influential extent
`bytlmoun‘eul
`.-.. .. .... n .
`§ an. Ad herence'1n 111111111011: that. are heated by 11111: current. [15.515113 through
`them. Reflistauw walding .........................................
`§ 31. About. statioma‘y contactxs'm. pracstice. .- .
`. ... . ......................
`A. GenemI survey of 1.111: 19916 111.111. mutant Elma plfly1n practical contacts.
`159 -— B. Mmamemc-‘ntfi111' E L. on eanmets made wifhflut injpflct [11' Eli-
`ding, 162.
`-— U. Ulampad com-5.0811. 8.013311: 1.1215.
`. Dimensionmg fl contflct W111) respect to 11.11 heating” _
`. Contact efiwta in nauhfin mibrflenes ......_
`.... . ....... ......_.
`. Unntflut noise in fl’stfltianmgy 11131111151.
`. .
`.
`1 ...............
`.
`._ . 001116.131. 111111 gem'icnnducfinrs. Hantificatiorn.T1-ansiatnr'a. $1111.11: 61130111—
`.fisfltian ...... .1. .
`A. Int:n1:1untion.-.181:1.B 0011125111. bntwmnamctal 11.111121321111001111.2216:
`3.11:1 1th nachifying Latoya-1y- 188. — C T1113 p—n-junu’oinn. 190. -
`D. Types of semipund‘uutifig 1191211521.... 191.
`:- E. Remarks about
`tranflia'tom. 194-. — E. Rmnrk concerning 12111: contact between Eilimm
`carbide crystals. 1911.
`-—. G. Static elactflficatinm 195.
`'. 02115191149113 rheostflts. Eleet'a'ie reaistanme of pressed powders . . . . .- ..... 196
`
`beaming materiais. 222. —F. Ball hfimiug's. 224.
`
`135.11 II
`Sliding; 001115019
`
`. . .. . .
`. Survey concerning friction 2111111111321:
`A hatrufluctlun. 199 — I1. T1111 frit’sfiou 11.13:]; zéflififing from P13512111
`duforma‘blo'n.
`21110.
`...
`(3. "1111 2611912111113. 11312-1121 of 1.1113 fi'iefiou. 201. -
`D.D..'.l'1'1e moi-35111: 0f 1.111111011151111. 11.115111 1111:1111; 11111111115. .203. u 13.131111101111121
`law of frictinn. 21M.— F. 2111:1111: the chmactiarmfic value of 1.1 s: 112111
`freshlyuleamml1111:1111 mum“:111 11312087 (1.221111011111 bimetnlhn-11011-
`11112111. 201.1 — 1-1 Friction betwaen nnn-mmilmfing members. 20'?- ~
`I. Devicfefi fa: 1511a inyesfigafiion 017151191;me 2117. —J. Refilling; fi‘iction.
`207'. — K. The -in:flu&‘u¢fl {1f adhesion Wfififil‘ an friction. 305.;-— L. The
`work (5f 1.1.113 31111Mit1étipp. 209.
`
`. Early absurvahqns on the high fdcfiun in Lilli-11.11 met-21.11113 contacts”: in
`1211131111111, andflihe ih-Hueme. uf'admitfltnfi games
`.
`. . w . .. . . .
`. .
`,
`.Baundmy lubricflfion
`.
`...
`.
`.
`A.Fea1;ur55 of buundary- luhr1um49u.2'12.— J3.D1seusamu 111‘ two
`competing t_h1:r;1:2ias nf 110111111557}
`lubrication. 216. — G. Lubricating
`pmntlw. 2‘21. —' D.
`1512111113;
`lflj'er. 221. — E. metics mquit'ed (XI
`
`..
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`Page 7 of 13
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`i 'onbentE
`
`§ 40. Theory of friction and wear on carbon contacts. Lubrication by means of
`solid lubricants as irreplfite and. molybdenum disulphide ............
`A. lntmduotjon. 224-. — B. Friction of when brushes as dependent
`on the ofimtution of graphite basal plows. 226. — C. High altitude efi'e-ct
`01:1 brublh wear. 227. -—- D..Adjmnts. 9%. u- E. Graphite and molybde-
`num sulfide powder as lubricant. 2-29.
`. ..
`.
`.
`.
`.
`_ _
`.
`.
`§ all. Measurements on specific {Elation force.
`§42. Stick-slip motion. The tempemtwc 5:: tumor-lilacs.sliding contacts .....
`A. Stick—slip or jerky motion. 234. u 13.11113 temperature in current.
`loss sliding contacts. 235.
`§43. Statistical. study of the electric «induction and the friction of sliding
`contacts. Radio-.noiseiuatidjnguontscte
`..
`§ 4.4. Friction weal: 111 metallic ammo: Without current; ..................
`A. Introduction. 242. — B. Size and frequency of wum' fragments
`appearing (Inning periods of adhesive wear. 243. — (1 Details of the
`formation of wom- detritus. 244. D. Why liquids, emu the deposit
`[tom air humidity, are able to inflmmce weer without greatly [fleeting
`the Eviction coefficient. 245.
`-— E. The work necessary to lama-l: oilc a.
`Wee: fragment. ME. — F‘, Formula for classification of typos of fi‘iction
`weer. 246.— G. Friction wear in currcntless sliding contacts represented
`11y ii - 105 Z, which is wiculuted employing the hardness, .H, of the softer
`member. 248. — H. Wear in sliding contacts of measuring apparatus.
`253.
`
`F1
`
`224.
`
`2!]!
`234
`
`237
`242
`
`to :711.1:.
`
`21539
`
`27F:
`
`.
`
`. . . ............... _. . . . .
`
`§ 45. Electrical performance ofcarbon brushes onrings and commutetms when
`arcing is excluded ...........................................
`A. Litmdutt10n254. -- B Early investigations on the dark collector
`film. 265. —C.Chem1cs.l analyst. of The collector Lilm. 259. —D Structure
`of the film. 259. — E. Osofllogmphic inwuatigotions oI {fittings DI the
`collcctnr film. 259. H F. More about the film generation pmticulurly in
`the “static” state. 262. — G. Two brothers in the same track. 26-4.
`:5; 4:6. The temperature in 11 contact between 11 carbon brush and 11 copper ring
`or commutator
`. .
`.
`.
`. ..
`A Introduction. 285. - R. Qupcrtrvmpcmiure of the contact. cur-fare
`shove the temperature of the bulk of the ring. 266. H U. The temper-
`ature in the h ottcst section of the brush. 267.
`§ 47. “rear and fi‘lction in the brush-ring contact ........................
`A.1ntrcduction. 269. — B. .lfiflucnce of the current on the wear in
`absence of nrcs. 269. — G. Numerical data of bruch qualities. 272. a
`D. Abrasion of the slip ring. 2T3. —- l3. Wear in the blush-commutator
`contact. in case of arcing. 274. H Ii‘. Friction betwcon an elechngra-phitc
`brush 111111 copper ring 275-
`§ 43. Commutation problems .........................................
`A.L1tmuluction JTE. — B. Computation of ran-dine] conditions £01
`good commutation 279. —- O Aiming. 281. - D Numerical oxnmple
`mferrmg to a d--c gonnmtor with 2 poles for about 50 111111). 233 —
`Li. Brush contacting seteral segments simultaneously.
`£5811. — F. So-
`called short -cireu.it currents to the brush. 2.—sfi G. The importance
`of the elasticity of the brush for thc commutation. 287. u H. The
`appropriate value of the. 13me to he induced in an. armature winding by
`the field of the inturpoles. 238.
`§ 49. Current collectors for trolley Bald . . .
`
`.
`
`.
`
`. . . .
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`Page 8 of 13
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`
`
`XI]
`
`("cutouts
`
`Part 1.11
`
`Electric Phenomena In Switching contacts
`
`.
`. _
`5.101911111110113 and high power breakers .
`A. Intioductiou. 29L}. 7 B. Breaking of a-c 290 —0.11.1111“; 11111111131
`29"... —IJ. Dhcct 11111111111: switches. 292. — E. Quenching circuits. 2'93. -.
`F. Material transfer at switching. 295.
`§ 51 Ignition of 11103 in switches ................................
`:1. Introduction 293. 7 13. Electric breakdown in the. gap between
`clean metallic electrodes at atmosyherfic pressure. 293. — C. Ignition
`of an arc in 11. closing contact. 295. — D. Drawn arcs. Floating. 291. —
`E. Roignjtion of the are. 299.
`§52.T}i.schargetuamients
`§53. VIcharacteristics of the s’ra-tionury are in air. and their use for ca]-
`quat-ing the: dumtion oi short arcs
`.
`. . .
`.
`A. Introduction. 3114.— B.(11)nervnt.ious on11re111zi11g conidcts. 304.
`—- C. The use anI- (1-111‘111113111111131 1'01: determination of arc durations.
`310. — D.
`31111191111311 Vl-chamncteristics in 1101111111 atmosphere. 31.1. —
`E. Determination 01‘ J... and V,“ by air] of one osnfllogram and Diagr. X1.
`314.. — F. Use of the resistance lino together with arc-characteristics
`for the problem of 110W a. constant iuln'ent is shared between an arc
`and n1] ohmic 11911191113103 both in para-Hal. 314. 7 G. Survey of the method
`of applying the resistance line—together with use characteristics. Condition
`of stability. 31:"). — H. Semiconductiug resistors pmallel- to the urn. 315. —
`I. Vacuum arc. 316.
`
`290
`
`293
`
`302
`
`304
`
`§ 54. 111mm. Oscillations generated by Ii 711 arcs .......... ................. 315
`§5n.15mmcing.
`__________ . ................. 313
`§ 56. Mechanical erosion and 11111113111115; phenomena that are typical for sliding
`and switching contacts .......................................... 321
`A. Inn-oduct-iou. 3'21. —— B. Mechanical material transfer. 332. 7 El. Cat-a.-
`lytic efi'cctu in switching contacts. 323. — D. Frictional Oxidation.
`323.
`--. E. Oxidatinn in H191 arc. 324.
`
`§ 57. Methods to suppress or minimize arcing timing switching ............. 325
`A. Introduction. 326. 7 B. Quenching by means 01' a. resistor. 3211. r
`[1.
`[Japacit-ive quenching.
`BEE-'1'. — D. Arc quenching in the contact
`rectifier. £128. - E. Wcakening of the are between barriers, magnetic
`blowout. 1125].
`-— I". Motion of an arm in a magnetic field. 330.
`. . 331
`§58. Arc duration 1.11 contact making with voltage below 2-00 to 300 volts .
`A. Introduction. 331. — B. fi-aicula-tions with rcspcct
`to thc wiring
`Ilia-gram {58.02) with 111115.113? charged capacity. 331. ~— (3. Inductance
`1.— 0. and consequently luff: [I 111 the circuit
`(58.02). 334. 7 D. Float.-
`hig. 335. — E.Eml.uiricn.1 fi‘JI'TI'IlllH. for I“,
`the life of the arc, 111 the
`circuit (58.02). 336. — 1‘. Battery instead of'C, equivalent. to 6' = ca. 337.
`§ 59. 111-11 duration on breaking contact. Single circuit ................... 338
`A. Ohmic circuit according to wiring din-gram of Fig. (59.01}. Operation
`1'11 air. 33%. 7 B. Ohmic circuit. Open‘atiOn in a vacuum. 338.
`-—
`0. Inductive circuit ace-orthug l-u wirhlg diagram in Fig. {59.04). Caps.-
`city of the leads neglected. Operation in air. 3:13. 7 D. 'f‘hn quantity
`Of elccmicity. 9‘, that flows through a drawn are with the iife time 1".
`3:11. 7 11‘. Influence of the capacity of the loads. 31?.
`.
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`Page 9 of 13
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`Page 9 of 13
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`

`Con Lents
`
`.X 111
`
`§ 50.3111 {inret-ion and other phenomena in on are queunhins: nimuit. oncoming
`to wiring Diagram (£10.01)
`. ..
`.
`.
`. .. 342
`A. General equations [or the quenching nirrliitwhen quenching 11.11 are
`on breaking content r in position 155. 343. — R. Us.Ha 11+ V“ A... constant
`343. - C. V“ 2: Va» and are current f, considerably gmater than I“.
`344. — D.
`l7“ riifi'oring elightly from Fm, and the short circuit (gm-rout,
`1,. lying in the range between I“ and a fewnmp. 3-1.5. — E. Note. non-
`cerninn tho position of'r. 347. — F. Empiriwl fen-mule for the nebula.-
`tion of the arc 11131.1 constant mmningminrfityofthc circuit ofFig. (60.01}
`miller run}: conditions that the are generates oscillnt-ions. 347. - 61. Con—
`(lit-ion for no brea-kdownof'thngop lam-worm theeeyorating electrodes.3itl.—
`l:L Calculation of the voltage- V, between the electrodes as function of
`the time, i. in 111151: of no 1111'; 35”.
`
`§ 81. Quemhjng of RTES by rr'aietmu: parallol to the operating content. or
`parallel to the inductive. coil.
`............................... 352
`A1 Quenching with 11'
`in posit-on 11. 352. L B. Are quenohing with r in
`Position [1. 35—1..
`§ 62. Distinct types of urea in relay contacts .......................... 354
`Alntroduction 354. — B. Tho power balance in tho short are deter-
`mine the prevalence of the evaporation fiom the anode. 355. —C.. The
`plasma are. 356. 7 D. lie-marks. 357.
`§fi3. Material Lransfer'm switching contacts ............................. 358
`A“ Definition of the major types ol material tramsfer 358. —E. Material
`transfer at nontnct opening. 359.
`- -C. Material
`transfer at unnLnL-L
`make. 383.
`
`§ 34. Monaurcment of the material t-rarm'fer in ewiLoln'ng contacts, particularly
`with normal electrodes
`.
`. 353
`A. Introduction with definition of electrode 131365 nnrl symliols. 353. -
`13 Determination mc the amount of material trnnsfor that13 produced in.
`plasma. ares between normal oloctrodes. 364. — 0. Method to determine
`an: and. mfim general. 365. u D. Measurements ofbridge transform opening
`contacts. 356. u E. Determination of the coefficient :J.,Wl1icl1 noeording
`to Eq. (63.10) characterizes the material. transfer in short area between
`normal electrodes. HEB.
`-— F. The final
`length. 5,... of tile short are.
`370. — G.Abnorm;1l, short
`:1er with zero or a. small material transfer
`from the anode. 371. — H. The amount of material tmmfer during
`floating. 372. — I. The disintegration 111‘ the onthodein glow discharges.
`373 - J. Material transfer at omit-ant olos'urs without bouncing. 374.
`§ 65. Bridge material transfer in the shape of pips and spires . . ............ 3'75
`§ 66. Them-v of the electric material transfer in switching contacts. History
`of this theory ................................................... 376
`A. History. 376 —- B. Explanation of the material h‘nmsibr amused by
`them-L 378. —C.P1esonttheor_\ ofthe tu-idgetrsnsfer.3"9-D.TH0111E60N
`oEoot. 3'79.
`-— E. Punish: eifeo‘b. 383. — F. KOEIER e-fl‘eot. 384. R
`G. Comparison between calculated and observed magnitudes ofthe 1311'6go
`transfer. 388.
`
`§ 67. Numerical examyle on tin: calculation of material transfer for 21 oil ver
`Pontaetwitli [:npnniiiivuarc quench __.. 337
`§l38.Mercuryswnchcs...“........_.._._.........-..................... 388
`
`Page100f13
`
`Page 10 of 13
`
`

`

`448
`
`:13 recovery
`311111-111 hardening, atomic tlifl‘usjon PBBDJJLHBDHI
`§I. Harfinaafi,
`.407
`aodoroo'p... .....................................
`A. Survey of the theory of plastic dhlorermkm of solid bodies and of
`diffusion phmnmneno. 4117. i B. Hordnm as defined by the ball melon-
`Mt-ion test. 410. — O. Brittle materials. 413. —D. The work consumed by
`a. plastic deformation. 4] =1.
`. . . W. .
`. Eleoimmo conduction111 solids.
`14.131119ng bamd scheme. 414. — B.Dieiiiibutmn ol'1113 1519211121118 on the
`energy 1311313 «F :1. band- with 3191101111 Kimonos to the condmflm bud (if
`.1. metal. 411}. — II}. Patontlfllhmim Thnérmiouic amission of. ale-161mm.
`4.1-9. — ,D. Addmflll. about?“ 11- and p—mn'cludtirm. 420.. —— E. flunk-111.1;-
`duction. 421. - F. Potmud] bawieljg 8.1113 BqIIflibfimn 12011641511011.9111
`contact-s. .424. — -G.-Tl:'1£ 1211311121151 conductivity. 1‘. mthfi [11w 01r “1311311.
`MANN, Flam and Lomxz. 423-.
`. .
`.
`.
`.
`.
`Turuu-l 011m. Thurmioni'c emismon 3.1.111 [iold enfiwion
`11111.
`A. Them-51211111511]- basia 13:11: the tabulations. Classes I and II 41- wield/ELEM};
`ptm'63.11.43. 429. ._. B. Field emission and tihermionie emié3iou aidlwtad
`bythofionomm 01:11:31.1. 433. —-G. Tunnalmsistifit'y 435. —.D Comparison
`betwoan tunnel (111.111.1111. and thormionie 131111361111. according ’16 1032111113..
`(IH,13).V437. - E. Thmml e'fi'heh when; hot-h filooiirodo'a am of“ the 311111211:
`semi-conducting mférial. 4318'. — F. Remark cqnceroing‘fihbfield strength.
`439. -- G. Tunnel Gun-Entaomss a gap thatrywrwunfln a. mebaific contract
`consiaising of a mirau‘lar'opot'wi‘th the Tflidl'flfi 11.439.
`.....
`.Su-11131111113, 3131111113» 11.11121 thin-ma] conductivity: of carbons . . .- . . . .
`A Introduction.
`61131-121116 lat-i944 440. — 13.0mm; grades. 442 -—
`C. Graphitization. 443. H 33!. Elontfle mduc'tivity of carbons. 444. —
`13.12am oonfl'uoti‘vity of carbons. 447.-
`1111'. Hydrodynamic or 111.101;
`111.111 lubrication . . .
`
`A C
`
`ontouta
`
`390
`. . ............
`.
`.
`Appliuaflan of. statistics to surety of oontact make .
`A. handout-1011. 390. —- B. Testing surety 01 contact make- wibh single
`macro mutoat‘s. 391. -— 0 E3901; of twin contacts. 393.
`
`The chowe of cont-MI. material and mntaot- shape for praatinol appli-
`catiuna . . _.
`.
`._
`A. Permanent. Miami. 394.“—3111111310 1111111413111. 3134. — (J. High
`J'egebiiivo operation relay 00111412143934 D Light duty relays for
`mdium frequencies.
`3196. 7 E. Medium duty wimuii breakers 111.111
`coowotors. 396. — F. Heavy duty circuit Ema-km with up to thousands
`of n-mpenaa and. 701115.395. —» 14.131111ng 1101211111113 l'm:
`resistors and
`appara‘bus. 397. — "FL-Remark about nomwvidjng in'omrhoo and wolfmm-
`carbide tom-3.013. 3971'.
`
`XIV
`
`§5‘9.
`
`§ 70.
`
`Part IV
`
`Bison-y
`
`. Hist-Dry of early mvestigotio'ns ori contoots ;....... . .
`A(hntmreaistanca 398. r—B..M112;roplione and 001191-91- 401. —1:‘-. (“1111131113
`cousLLLL-Liofi 405
`
`398
`
`Appondims
`
`I
`
`§IV.
`
`440
`
`.............. .- . . .
`
`Page 11 of 13
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`

`

`Remarks about threadlike moleflic. formations , ................... 4 .'
`Some fundamental formulas concerning the electric discharge ....... 4
`A. Introduction. Kinetic fundamentals. 455. —B. Drift velocity. 456. 7
`C. Thermal
`ionization. Baha’i: equation. 457. — I). Plasma. 457.
`._
`E. Current in vurruum restricted by the space charge of the current
`omiers‘ 458.
`
`Calculation of the size of the load bee-ring urea: and of the preeeum
`on it in experiments by Born and Beware-rm [l] ................. 475
`.................................................... . ........ 4TB
`,
`............................................................ 481
`§XI.
`Author and literature index
`
`Contents
`
`XV
`
`General theory of the are that appears in relays ..................
`A. Introduction. 459. —- B. Reminder of elements of the theory of elon-
`tn‘c discharges in gases. 460. - 0. Thickness of the cethodelayer and
`metal vapor preeeuro Within it. 462. e D. Definition of the examples.
`463. -- E. Current density J+ of LL10 positive ions and Jr' ofthe primary
`electrons, at the cathode. 455. - F. In no afunction of T and p. 465‘ —
`G. Companieon with measurements. 4-57. — H. Power balance at the
`cathode. 461'. -— 1. Summary of the results concerning cathode pheno-
`mena. in arcs between non-refracwry electrodes. 469. — J. The power
`halenoe at the anode. 470. — K. Cathode of refractory materials as
`carbon and onram. 471. — L. Why is the voltage of a. short are oft-ho
`order of 10 V? 471. -—- M. Movement oj'the are spot. 472. -—- N. Current--
`voltage characteristics of area. Arc life. 473.
`
`Subject index ....................................................... 514
`
`Page 12 of 13
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`

`

`Part I
`
`Stationary Contacts
`
`§1. Introduction. A simplified summary of the theory of
`stationary electric contacts
`
`An attempt to present the concepts of the contact theory in such a
`sequence that none of them is used before being thoroughly defined would
`lead to a very unwieldly style. For example, the fundamental concept of
`contact surface can not be treated in detail before the constriction resis-
`tance has been defined, since determinations of the conducting areas are
`based on the measurement of constriction resistances. Again, the concept
`of the constriction resistance can not be thoroughly treated without rc-
`ferencc to the contact areas. Therefore, it seems preferable to introduce
`in a provisory manner some important concepts in an opening paragraph,
`allowing a. more elastic and agreeable exposition in those which follow.
`The introduction is given a quantitative character by means of some
`calculations. based upon an artificial model of the current flow lines
`which highly simplifi es the treatment. In the later paragraphs the same
`model is used for the calculation of particular problems.
`The term electric contact means a releasable junction hEtWeen two
`conductors which is apt to carry currcnt. These conductors may be called
`contact members, or simply contacts, when no misinterpretation is likely.
`The positive and negative contact members are also called anode. and
`cathode respectively. Even when the contact is opened, i. e., the members
`are separated and no actual contact exists any longer, one speaks of an
`open contact. Its gap is the shortest distance betwoeu the surfaces of the
`contact members.
`'
`
`The force that presses the contact members together is the mechanical
`load or simply the load, P. No surface of a solid body is perfectly plane,
`and if the contact members Were infinitely hard, the load could not bring
`them to touch each other in more than three points. But since actual ma-
`terials are deformable, thepoints become enlargedto small areas andsimul—
`tanccusly new contsctpoints mayr set in. The sum ofall these areas or spots
`is the load bearing area, A3,, in which the pressure, p, its-finite. Ab can be
`generated merely by elastic deformation. But, because of their uneven-
`1 Helm. Electric Contacts
`
`Page13of13
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`Page 13 of 13
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`