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Changes
→6.3 Design Technologies for Contacts
|During brazing carrier may get soft
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|Slip rings with high reliabilityVertically welded wire segments|Low and consistent contact resistance at low contact forces|Brushes: Au Ag, Ag alloys, Ag/Ni, AgPd, AgPdCu; Slip rings: Au alloys, Ag alloys (Rhwire 0.6 ~ 5 mm Ø)|Contact parts for control functions and power engine- ering; For economical manufacturing at higher currents: Ag/C brushes against Ag slip ringsquantities|Brush wires, stamped brushes; solid, clad, Welding and subsequently heading or electroplated slip rings, Ag/C formed partsorbital forming of head shape
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|Sliding contacts in miniature motorsHorizontally welded wire and profile segments|Very high frictional wear resistance, sure contacting even at very low contact forces|Ag and Au alloys, Pd alloys, Au Ag, Ag alloys, Ag/Ni, Ag/MeO, Ag/C in strip or profile form, Miniature profiles - also multi component alloys-layered (profile width 0.2 ~ 5 mm)|Brushes from flat rolled wire or stampedContact parts for communication, measurement, controls and power engineering; collector hard gold electroplated or clad, or made from miniature profile segmentsvery economical with respect to precious metal usage|Welding synchronized to stamping / forming on special equipment
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|Centrifugal controllers for small motorsWeld buttons|Little shape changesAg, Ag alloys, Ag/Ni, Ag/MeO on Steel, Ni, Monel; Ag/W, defined contacting at very low contact forces and high frequency of operationAg/Mo (1.5 ~ 10 mm Ø)|Pd alloysWelded for example to steel springs or thermostatic bimetals for temperature controls|Contact rivets, contact screws, welded partsMetallurgical bond through simple projection welding remains strong in temperature cycling applications
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|ConnectorsTungsten weld buttons|Low contact resistanceW on Ni or Ni-plated Fe, corrosion resistance, sufficient frictional wear resistance, good sliding capabilities(2 ~ 6 mm) with weld projections|Ag Contacts for controls, ignition points and Au alloys, Pd, PdNihorns; For automotive and consumer electronic at low operation numbers: Sn and Sn alloysarcing contacts in special relays|Electroplated layers or clad, often Au flash plated, mostly with Ni substrate layer, stamped parts from hot tin dipped stripFor change-over contact welded on both sides of carrier
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|Telecommunication relaysBrazed contact tips|Reliable contacting even at high operational frequency|AgAll materials and dimensions, oxide and graphite containing materials with brazable backing, AgPdcarrier parts from Fe, Au Cu and Cu alloys, PdRuat higher strength requirements also CuCrZr or CuBe|Medium and higher load switching devices for power engineering|RivetsBraze alloy layer with low meting point, welded profile segmentscarriers may soften during brazing
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|Reed relay contactsClad contact materials (Contact Bimetals), totally covered or with inlayed strips|High reliability at low currents independent Ductile precious metals on Cu and Cu alloys, minimum precious metal layer 2% of total strip thickness for Ag and Ag alloys, 0.5% of atmospheric environment|total strip thickness for Au, alloys (Rhwith Ni intermediate layer), max. inlayed thickness 50% of total, strip width starting at 2 mm|Clad contact springs; stamped and formed parts for communications and power engineering; aluminum clad for bonding capability|Switch paddles FeNi with partially diffused Au, (electroplated Rh)Metallurgical bond; inlayed strip stamped perpendicular or at angle to strip direction; avoid bends at the cladding edges
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|Relays in electronic circuitsStrips or profiles with brazed contact material layers (Toplay material)|High reliability at low switching loads Ag, Ag alloys, Ag/Ni, Ag/MeO on Cu and compact device design|Au alloysCu alloy carriers, total width 10 ~ 100mm, AgPdcarrier thickness 0.3 – 5 mm, Ag alloysstrip cross section from 0.3 x 3 mm2, strip thickn. to be < carrier thickn.|Stationary and moving contact bridges for power engineering switching devices|Stamped springs from seamContact layers brazed with Ag brazing alloys; strips re-welded profiles, welded miniature hardened during profile (tape) segments, contact rivetsrolling
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|GP relais (Elementary relays)Seam-welded contact strips or profiles|Low arc erosionWire, high weld resistancestrip, low and consistent contact resistanceminiature profiles (solid or clad) welded to Cu alloy carrier strip (0.3 – 3 mm Ø or up to 5 mm width)|Ag/NiSwitches, Ag/SnO<sub>2</sub>pushbuttons, (Ag/CdO)relays, Ag/ZnOauxiliary contactors,AgNi0.15, (Ag)sliding contacts|Solid and composite contact rivetsBroad usability, highly economical, welded miniature profile (tape) segmentsthin spring hard carriers can be used
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|Automotive relaysMiniature profiles (Weld tapes)
|Low material transfer, low contact resistance, high weld resistance
|AgNi0.15, Ag/SnO<sub>2</sub>, Ag/Ni