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→Silver-Metal Oxide Materials Ag/CdO, Ag/SnO2, Ag/ZnO
''Powder metallurgy'' plays a significant role in the manufacturing of Ag/SnO<sub>2</sub> contact materials. Besides SnO<sub>2</sub> a smaller amount (<1 wt%) of one or more other metal oxides such as WO<sub>3</sub>, MoO<sub>3</sub>, CuO and/or Bi<sub>2</sub>O<sub>3</sub> are added. These
additives improve the wettability of the oxide particles and increase the viscosity of the Ag melt. They also provide additional benefits to the mechanical and arcing contact properties of materials in this group ''(Table 2.26)''.
'''Table 2.26: Physical and Mechanical Properties as well as Manufacturing Processes and Forms of Supply of Extruded Silver-Tin Oxide (SISTADOX) Contact Materials'''
In the manufacture the initial powder mixes different processes are applied which provide specific advantages of the resulting materials in respect to their contact properties ''(Figs. 2.87 – 2.119)''. Some of them are described here as follows:
Fig. 2.88: Softening of Ag/SnO<sub>2</sub> 92/8 PE after annealing for 1 hr after 40% cold working
[[File:Softening of AgSnO2 92 8 PE.jpg|right|thumb|Softening of Ag/SnO<sub>2</sub> 92/8 PE after annealing for 1 hr after 40% cold working]]
Fig. 2.89: Strain hardening of Ag/SnO<sub>2</sub> 88/12 PE by cold working
[[File:Strain hardening of Ag SnO2 88 12 PE.jpg|right|thumb|Strain hardening of Ag/SnO<sub>2</sub> 88/12 PE by cold working]]
