Downhole tool and application method

A kind of downhole tool for well bore, the tool has the plug made of reactive metal material, and there is core rod end, the core rod end has the fault point defined by interior grooves, in the range of fault point wall thickness can arrive about 0.1 inch at about 0.03 inch.The downhole tool also has the first one-piece metal sliding block around plug setting；Around the second one-piece metal sliding block of plug setting；And the lower sleeve portion for being arranged close to second sliding block around the plug and being engaged with the core rod screw thread formula.