With its special property,the mental W.is suitable for the TIG welding and the other electrode materials alike.To enforce the welding power of W electrode by adding rare-earth oxide in the mental W.,the property of W can be improved greatly ,with better electrode arc,more stability of arc column,and less burning loss of electrode.The usual rare-earth annexing agents include the following:cerium oxide,thorium oxide,lanthana,zirconia and yttrium oxide ect