Changes

====<!--6.4.5 -->Physical Effects in Sliding and Connector Contacts====

<table class="twocolortable" style="text-align: left; font-size:12px;width:40%"><tr><td>dV/dx = k x FK F_K /3 HWH_W</td></tr><tr> 3 <td>dV/dx Wear volume in mm ³ per slide path length in mm</td></tr><tr><td>k Coefficient of frictional wear</td></tr><tr>HW <td>H_W Hardness of the softer material<br />(Brinell or Vickers units)</td></tr><tr>FK <td>F_K Contact force in cN</td></tr><tr><td>'''Wear coefficient k during material transfer'''</td></tr><tr>-4 <td>Silver – Silver 120 x 10^-4</td></tr><tr><td>Platinum – Platinum 400 x 10^-4</td></tr><tr><td>Silver – Platinum 1.3 x 10^-4</td></tr><tr><td>'''Coefficient of fractional wear k during wear loss'''</td></tr><tr>-4 <td>Silver – silver 8 x 10^-4</td></tr><tr><td>Gold – gold 9 x 10^-4</td></tr><tr><td>Platinum – platinum 40 x 10^-4</td></tr><tr>4 <td>Silver – gold 9 x 10^-4</td></tr><tr><td>Silver – platinum 5 x 10^-4</td></tr></table>  [[File:Coefficient of frictional wear for the wear loss of sliding contacts Silver Silver.jpg|right|thumb|Coefficient of frictional wear for the wear loss of sliding contacts Silver/Silver and hard gold/hard gold as a function of the contact force]]

<xr id="fig:Contact resistance Rk as a function of the contact force Fk"/><!--Fig. 6.16: --> Contact resistance R _k as a function of the contact force F_k for different surface coating materials. Measured against a spherical gold probe; I = 10 mA, U < 20 mV <xr id="fig:Contact resistance Rk as a function of the fretting wear cycles"/><!--Fig. 6.17:--> Contact resistance R_k as a function of the fretting wear cycles for different surface coating materials <div class="multiple-images"><figure id="fig:Contact resistance Rk as a function of the contact force Fk">[[File:Contact resistance Rk as a function of the contact force Fk.jpg|right|thumb|Contact resistance R_k as a function of the contact force F _k for different surface kcoating materials. Measured against aspherical gold probe; I = 10 mA, U < 20 mV]]</figure>

Fig. 6<div class="multiple-images"><figure id="fig:Contact resistance Rk as a function of the fretting wear cycles">[[File:Contact resistance Rk as a function of the fretting wear cycles.17: jpg|right|thumb|Contact resistance R _k as a function kof the fretting wear cycles for different surfacecoating materials]]</figure></div><div class="clear"></div>

 <figtable id="tab:Surface Coating Materials for Connectors"><caption>'''<!--Tab.6.4: -->Surface Coating Materials for Connectors'''</caption> {| class="twocolortable" style="text-align: left; font-size: 12px"|-!Manufacturing method !Coating materials!Intermediate layer!Hardness HV!Frictional factor|-|Electroplating|Tin<br />Nickel<br />Nickel-phosphorus (NiP 6 - 15)<br />Silver<br />Hard gold (< 0.3 wt% Ni or Co)<br />Palladium with Au- flash (<0,2μm)<br />Palladium-nickel with Au-flash (<0.2μm)|For brass: Copper or Nickel<br /> <br /> <br /> <br />Nickel, Nickel-phosphorus<br />Nickel<br />Nickel|50 - 90<br />300 - 600<br />500 - 1100<br />70 - 100<br />100 - 200<br />250 - 300<br />300 - 400|0.5 - 1<br /> <br /> <br />0.5 - 0.8<br />0.2 - 0.5<br />0.2 - 0.5<br />0.2 - 0.5|-|Cladding|Gold-nickel (AuNi 5 -10)<br />Silber-palladium (AgPd 10 - 30)|Nickel<br />Nickel|160 - 200<br />120 - 170|0.2 - 0.5<br />0.2 - 0.5|-|Hot-dipped tinning|Tin|Inter-metallic compound[[#text-reference|⁽¹⁾]] Tin–copper|400 - 500||}<div id="text-reference">(1) is formed during hot tinning process</div></figtable> <div class="clear"></div>

[[Application Tables and Guidance Guideline Data for the Use of Electrical ContactsContact Design#References|References]] [[de:Physikalische_Effekte_bei_Gleit-_und_Steckkontakten]]