Silver and pure silver possess very high electric and thermal conductivity, low and stable contact resistance and good processing and welding performance. Because of a little nickel added into silver, pure silver has higher intensity and thermal- resistant performance than silver under same contact resistance. Therefore, its fusion resistance and arc burning resistance are better than that of silver. Under the same application condition, pure silver can take the place of silver. AgNi material with 10-40% of high melting-point metal nickel has high electric conductivity, low contact resistance and little burning loss. This material has little transfer when connecting and breaking direct current. To be widely used in AC and DC low-voltage devices, such as relays, instruction switches, can switches, breaker, assisting contactors. Instrument switches, optical control switches, temperature controller and washing machine timers. AgZnO has higher thermal stability than AgCdO, therefore, has better fusion resistance and arc burning resistance. But its contact resistance is high. Since AgZnO is innoxiously and has no pollution to the environment. It is one of the ideal materials to substitute AgCdO at present. AgCdO is the most commonly used contact material at present. CdO obviously increase the fusion resistance or cohesive resistance of the contacts at the moment of getting through big current. The sublimation of CdO cools the contact surface and lowers the arc energy and extinguishes the arc. Therefore AgCdO can meet the main requirements of low-voltage apparatus to contacts. Such as arc burning resistance at big-current switching-on, low and stable contact resistance under various loads and good arc extinguishing performance. Since Cd pollutes the environment, other materials are substituting it. It is used to low-voltage apparatus with medium or high load, typically used to micro switches, relays, protection switches, contactors and auto-switches. AgSnO2 and AgSnO2 In2O3 are the ideal environment-protective materials for substituting AgCdO. Since SnO2 has better thermal stability and higher hardness than CdO, AgSbO2 ABD AgSnO2 In2O3 is higher and it is more difficult to processing these two materials. It is