Silver-Tin Oxide (Ag/SnO²) Silver Tin oxide (Ag/SnO² ) mterils. speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. Over the pst yers, mny Ag/CdO contct mterils hve een replced y Ag/SnO sed mterils with -4 wt% SnO ecuse of the toxicity of Cdmium. This chngeover ws further fvored y the fct tht Ag/SnO contcts quite often show improved contct nd switching properties such s lower rc erosion, higher weld resistnce, nd significnt lower tendency towrds mteril trnsfer in DC switching circuits (Tle.3). Ag/SnO mterils hve een optimized for rod rnge of pplictions y other metl oxide dditives nd modifiction in the mnufcturing processes tht result in different metllurgicl, physicl nd electricl properties. Mnufcturing of Ag/SnO y internl oxidtion is possile in principle, ut during het tretment of lloys contining > wt% of tin in oxygen, dense oxide lyers formed on the surfce of the mteril prohiit the further diffusion of oxygen into the ulk of the mteril. By dding Indium or Bismuth to the lloy the internl oxidtion is possile nd results in mterils tht typiclly re rther hrd nd rittle nd my show somewht elevted contct resistnce nd is limited to pplictions in relys. To mke ductile mteril with fine oxide dispersion (TOS F) (Figs..4 nd.) it is necessry to use specil process vritions in oxidtion nd extrusion which led to mterils with improved properties in relys. Adding rzle fine silver lyer to such mterils results in semi-finished mteril suitle for the mnufcture s smller weld profiles (WTOS F) (Fig..6). Becuse of their resistnce to mteril trnsfer nd low rc erosion these mterils find for exmple roder ppliction in utomotive relys (Tle.3). Powder metllurgy plys significnt role in the mnufcturing of Ag/SnO contct mterils. Besides SnO smller mount (< wt%) of one or more other metl oxides such s WO3, MoO3, CuO nd/or BiO3 re dded. These dditives improve the wettility of the oxide prticles nd increse the viscosity of the Ag melt. They lso provide dditionl enefits to the mechnicl nd rcing contct properties of mterils in this group (Tle.6). In the mnufcture the initil powder mixes different processes re pplied which provide specific dvntges of the resulting mterils in respect to their contct properties (Figs..87.9). Some of them re descried here s follows: Ag/SnO² - (see DODUCO Dt Book pp. 79-9) ) Powder lending from single component powders In this common process ll components including dditives tht re prt of the powder mix re lended s single powders. The lending is usully performed in the dry stge in lenders of different design. ) Powder lending on the sis of doped powders For incorportion of dditive oxides in the SnO powder the rective spry process (RSP) hs shown dvntges. This process strts with wter-sed solution of the tin nd other metl compounds. This solution is neulized under high pressure nd temperture in rector chmer. Through the rpid evportion of the wter ech smll droplet is converted into slt crystl nd from there y oxidtion into tin oxide prticle in which the dditive metls re distriuted evenly s oxides. The so creted doped Ag/SnO powder is then mechniclly mixed with silver powder. c) Powder lending sed on coted oxide powders In this process tin oxide powder is lended with lower melting dditive oxides such s for exmple AgMoO4 nd then het treted. The SnO prticles re coted in this step with thin lyer of the dditive oxide. Further processing of these differently produced powders follows the conventionl processes of pressing, sintering nd hot extrusion to wires nd strips. From these contct prts such s contct rivets nd tips re mnufctured. To otin rzle cking the sme processes s used for Ag/CdO re pplied. As for Ag/CdO, lrger contct tips cn lso e mnufctured more economiclly using the presssinter-repress (PSR) process (Tle.7). The mrkings of the contct mterils re set up s follow: Ag/SnO² W P W4/ Short mrk for dditives nd production process Produced y powder metllurgy process With rzle nd weldle under lyer Totl oxide content (wt.-%) Min component (SnO²)
speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. Tle.6: Physicl nd Mechnicl Properties s well s Mnufcturing Processes nd Forms of Supply of Extruded Siler Tin Oxide (SISTADOX) Contct Mterils Mteril/ DODUCODesigntion Ag/SnO 9/8PW4 Silver Content Ag/SnO 9/PW4 89-9 Ag/SnO 88/P Additives Density [g/cm³] [% IACS] 86 [MS/m] Vickers Hrdness Hv WO³ 83 48 _ 9,7 79 46 6 Ag/SnO 9/8PW 9-93 x WO³ 86 Ag/SnO 9/PW 89-9 x WO³ 83 48 Ag/SnO 88/PW x WO³ 9,7 79 46 6 Ag/SnO 9/8PE 9-93 BiO3 u.cuo 9 Ag/SnO 9/PE 89-9 BiO3 u. CuO 84 49 Ag/SnO 88/PE BiO3 u. CuO 9,7 79 46 6 Ag/SnO 98/PX 97, - 98, BiO3 u. CuO 9 Ag/SnO 94/6PX 93, - 94, BiO3 u. CuO 9 3 Ag/SnO 9/8PX 9-93 BiO3 u. CuO 88 Ag/SnO 98/PC 97, - 98, x BiO3 u. CuO 9 Ag/SnO 94/6PC 93, - 94, x BiO3 u. CuO 9 3 Ag/SnO 9/8PC 9-93 x BiO3 u. CuO 88 Ag/SnO 9/8TOS F 9-93 84 49 8 Ag/SnO 9/TOS F 89-9 8 47 97 78 Ag/SnO 94/6WPX 93, - 94, BiO3 u. CuO 9 3 Ag/SnO 9/8WPX 9-93 BiO3 u. CuO 88 Ag/SnO 9/WPX 89-9 BiO3 u. CuO 83 48 6 Ag/SnO 88/WPX BiO3 u. CuO 78 6 Ag/SnO 86/4WPX 8-87 BiO3 u. CuO 7 4 7 Ag/SnO 94/6WPC 93, -94, BiO3 u. CuO³ 9 3 Ag/SnO 9/8WPC 9-93 BiO3 u. CuO 88 Ag/SnO 9/WPC 89-9 BiO3 u. CuO³ 83 48 6 Ag/SnO 88/WPC BiO3 u. CuO 78 6 Ag/SnO 86/4WPC 8-87 BiO3 u. CuO³ 7 4 7 Ag/SnO 94/6WPD 93, - 94, 9 3 Ag/SnO 9/8WPD 9-93 86 6 8 47 67 Ag/SnO 88/TOS F [wt-%] 9-93 WO³ Electricl Conductivity Ag/SnO 9/WPD 89-9 Ag/SnO 88/WPD 76 44 73 Ag/SnO 86/4WPD 8-87 9,7 7 4 8 Ag/SnO 9/8WTOS F 9-93 84 49 8 Ag/SnO 9/WTOS F 89-9 8 47 97 Ag/SnO 88/WTOS F 78 = Wires, Rods, Contct rivets, = Stris,. Profiles, Contct tips Ag/SnO² - (see DODUCO Dt Book pp. 79 ff) Mnufcturing Process ) doped ) doped ) doped ) doped ) doped ) doped Melt metllurgy internl oxidtion Melt metllurgy internl oxidtion Melt metllurgy internl oxidtion Ag cking c) coted Ag cking c) coted Ag cking c) coted Ag cking c) coted Ag cking c) coted Melt metllurgy internl oxidtion Melt metllurgy internl oxidtion Melt metllurgy internl oxidtion Form of Supply
4 7 6 4 3 36 8 Rp, 4 6 8 4 4 3 4 8 7 6 4 3 HV Edge 7 6 4 3 3 Rp, 4 6 8 Fig..89: Strin hrdening of Ag/SnO 88/ PE y cold working Ag/SnO² - 3 (see DODUCO Dt Book pp. 79-9) A 6 Rp, 8 4 4 7 6 4 3 3 4 HV Edge 4 A 8 44 8 4 3 9 HV Center 8 8 HV Center 36 Fig..88: Softening of Ag/SnO 9/8 PE fter nneling for hr fter 4% cold working 36 4 nd Elongtion A [%] 9 Tensile Strength R m nd. % Yield Strength Rp, [MP] 44 A Fig..87: Strin hrdening of Ag/SnO 9/8 PE y cold working 44 9 3 nd Elongtion A [%] speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. HV Center nd Elongtion A [%] 8 Tensile Strength R m nd. % Yield Strength Rp, [MP] nd Elongtion A [%] 9 HV Edge Tensile Strength R m nd. % Yield Strength Rp, [MP] 44 Tensile Strength R m nd. % Yield Strength Rp, [MP] HV Edge 36 HV Center 3 8 Rp, 4 6 8 4 A Fig..9: Softening of Ag/SnO 88/ PE fter nneling for hr fter 4% cold working
6 4 3 8 Rp, 4 6 3 3 7 6 4 3 HV 3 3 Rp, 9 4 8 A 3 4 6 7 8 3 7 3 6 4 HV 4 3 3 Rp, 9 4 8 3 7 3 Fig..9: Strin hrdening of Ag/SnO 9/8 PX y cold working Ag/SnO² - 4 (see DODUCO Dt Book pp. 79-9) 4 3 A A 4 3 3 HV Rp, Fig..94: Softening of Ag/SnO 98/ fter nneling for hr fter 8% cold working 9 4 8 3 7 3 4 6 7 8 A 6 3 3 Ag/SnO² - Tensile Strength R m nd. % Yield Strength Rp, [MP] 4 Fig..93: Strin hrdening of Ag/SnO 98/ PX y cold working 8 Fig..9: Softening of Ag/SnO 88/ PW fter nneling for hr fter 3% cold working 4 6 3 4 Tensile Strength R m nd. % Yield Strength Rp, [MP] 8 9 4 Elongtion A [%] A Rp, 4 4 8 3 8 7 4 HV Center 3 Fig..9: Strin hrdening of oxidized Ag/SnO 88/ PW y cold working 8 6 Elongtion A [%] speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. Tensile Strength R m nd. % Yield Strength Rp, [MP] 7 3 36 9 HV Center Elongtion A [%] 8 36 HV Edge 4 Elongtion A [%] Hrtdness HV nd Elongtion A [%] 9 44 Tensile Strength R m nd. % Yield Strength Rp, [MP] 4 6 4 3 Tensile Strength R m nd. % Yield Strength Rp, [MP] HV Edge 44 48 nd Elongtion A [%] 48 Tensile Strength R m nd. % Yield Strength Rp, [MP] HV 4 3 3 Rp, A 3 3 4 Fig..96: Softening of Ag/SnO 9/8 PX fter nneling for hr fter 4% cold working
3 3 A 3 3 A 3 HV 3 Fig..97: Strin hrdening of internlly oxidized Ag/SnO-InO3 88/ TOS F y cold working HV 3 3 4 Fig..98: Softening of Ag/SnO-InO3 88/ TOS F fter nneling for hr fter 3% cold working Cold Working %, 4%, 8% 8% 9 8 7 6 3 4 6 7 8 9 4% 9 8 % 6 Fig..: Strin hrdening of Ag/SnO 88/ WPC y cold working 9 8 7 6 7 3 4 6 7 3 4 6 7 8 9 Fig..3: Strin hrdening of Ag/SnO 86/4 WPC y cold working Fig.: Softing of fter nneling for hr fter degrees of cold working. Cold Working %, 4% 3 3 4% 9 7 3 4 6 7 Fig..4: Softening of Ag/SnO 86/4 WPC fter nneling for hr fter different degrees of cold working 8 3 4 6 7 8 Fig..: Strin hrdening of Ag/SnO 88/ WPD y cold working Ag/SnO² - (see DODUCO Dt Book pp. 79-9) Cold Working %, 4%, 8% % 9 8 % 7 6 9 8 8% speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. 3 nd Tensile Strength [MP] Elongtion A [%] 4 4 Elongtion A [%] nd Tensile Strength [MP] 4% 9 7 3 4 6 7 8 Fig..6: Softening of Ag/SnO 88/ WPD fter nneling for hr fter different degrees of cold working
Cold Working %, 4%, 8% 8% 9 4% 9 8 % 8 7 6 3 4 6 7 7 6 3 4 6 7 speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. Fig..8: Softening of Ag/SnO 88/ WPX fter nneling for hr fter different degrees of cold working 8 9 Fig..7: Strin hrdening of Ag/SnO 88/ WPX y cold working 6µm 6µm Fig..9: Micro structure of Ag/SnO 9/8 PE: ) perpendiculr to extrusion direction ) prllel to extrusion direction 6µm Fig..: Micro structure of Ag/SnO 88/ PE: ) perpendiculr to extrusion direction ) prllel to extrusion direction 6µm 6µm Ag/SnO² - 6 (see DODUCO Dt Book pp. 79-9) 6µm Fig..: Micro structure of Ag/SnO 88/ PW: ) perpendiculr to extrusion direction ) prllel to extrusion direction
speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. µm µm µm µm µm µm Fig..: Micro structure of Ag/SnO 98/ PX: ) perpendiculr to extrusion direction ) prllel to extrusion direction Fig..3: Micro structure of Ag/SnO 9/8 PX: ) perpendiculr to extrusion direction ) prllel to extrusion direction Fig..4: Micro structure of Ag/SnOInO3 88/ TOS F: ) perpendiculr to extrusion direction ) prllel to extrusion direction Fig..7 left: Micro structure of Ag/SnO 88/ WPD: prllel to extrusion direction ) AgSnO contct lyer, ) Ag cking lyer µm Ag/SnO² - 8 (see DODUCO Dt Book pp. 79-9) µm Fig..8 right: Micro structure of Ag/SnO 88/WPX:prllel to extrusion direction ) AgSnO contct lyer, ) Ag cking lyer
µm Fig..9: Micro structure of Ag/SnO 86/4 WPX: ) perpendiculr to extrusion direction ) prllel to extrusion direction, ) Ag/SnO² contct lyer, ) Ag cking lyer µm speterts or other rights of third prties re concemend. The informtion descries the type of mteril nd shll not e considered s ssured chrcteristics. ständ / eng. Tle.9: Optimizing of Silver Tin Oxide Mterils Regrding their Switching Properties nd Mteril/ Mteril Group Ag/SnO PE Ag/SnO 98/ PX Ag/SnO TOS F Ag/SnO WPC Ag/SnO WPD Ag/SnO WPX Specil Properties Especilly suitle for utomotive relys (lmp lods) Especilly good het resistnce Especilly suited for high inductive DC lods For AC3 nd AC4 pplictions in motor switches (contctors) Especilly suited for severe lods (AC4) nd high switching currents For stndrd motor lods (AC3) nd DC lods (DC) Good formility (contct rivets) Esily riveted, cn e directly welded Very good formility (contct rivets) Resistive lods (AC) Tle.3: Contct nd Switching Properties of Silver Metl Oxide Mterils Mteril/ Properties DODUCO-Designtion Ag/SnO Environmentlly friendly mterils,very high resistnce ginst welding during current on switching, Weld resistnce increses with higher oxide contents, Low nd stle contct resistnce over the life of the device nd good temperture rise properties through use of specil dditives, High rc erosion resistnce nd contct life, Very low nd flt mteril trnsfer during DC lod switching, Good rc moving nd very good rc extinguishing properties Tle.3: Appliction Exmples of Silver Metl Oxide Mterils Mteril Appliction Exmples Ag/SnO Micro switches, Network relys, Automotive relys, Applince switches, Min switches, contctors, Fult current protection relys (pired ginst Ag/C), (Min) Power switches DODUCO GmH Im Altgefäll 78 Pforzheim Germny Phone +49 () 73 6-66 Fx +49 () 73 6-66 Mil: olutz@doduco.net http://www.doduco.net Ag/SnO² - 9 (see DODUCO Dt Book pp. 79-9)