Changes

Silver zinc oxide contact materials with mostly 6 - 10 wt% oxide content, including other small metal oxides, are produced exclusively by powder metallurgy [[#figures1|(Figs. 76 58 – 8163)]]<!--(Table 2.28)-->. Adding WO₃ or Ag₂WO₄ in the process - as described in the preceding chapter on Ag/SnO₂ - has proven most effective for applications in AC relays, wiring devices, and appliance controls. Just like with the other Ag metal oxide materials, semi-finished materials in strip and wire form are used to manufacture contact tips and rivets. Because of their high resistance against welding and arc erosion Ag/ZnO materials present an economic alternative to Cd free Ag-tin oxide contact materials (<xr id="tab:Contact and Switching Properties of Silver–Metal Oxide Materials"/><!--(Tab. 2.30)--> and <xr id="tab:Application Examples of Silver–Metal Oxide Materials"/>)<!--(Tab. 2.31)-->.