Electrode for electric-discharge surface treatment and method for forming electrode for electric-discharge surface treatment

Abstract

An electrode for electric-discharge surface treatment, which is used in the electric-discharge surface treatment in which pulsed electric discharge is generated between the electrode and a base material in a machining fluid or in the air by using a green compact, which is formed by compressing powder of an electrode material, as the electrode, and by using energy of the electric discharge, a coating including the electrode material or a reaction product of the electrode material reacted by the electric discharge energy is formed on a surface of a base material, wherein a mixture of Si powder having an average particle diameter of not less than 0.3 μm and not more than 10 μm and hard material powder having an average particle diameter of not less than 0.3 μm and not more than 10 μm is used as the electrode material.

1 . An electrode for electric-discharge surface treatment, which is used in the electric-discharge surface treatment in which pulsed electric discharge is generated between the electrode and a base material in a machining fluid or in the air by using a green compact, which is formed by compressing powder of an electrode material, as the electrode, and by using energy of the electric discharge, a coating including the electrode material or a reaction product of the electrode material reacted by the electric discharge energy is formed on a surface of a base material,
 wherein a mixture of Si powder having an average particle diameter of not less than 0.3 μm and not more than 10 μm and hard material powder having an average particle diameter of not less than 0.3 μm and not more than 10 μm is used as the electrode material.   
     
     
         2 . The electrode for electric-discharge surface treatment according to  claim 1 ,
 wherein powder, which includes not more than 5 vol % of powder having a particle diameter of not less than 20 μm, is selected as the hard material and the Si powder which have the average particle diameter of not more than 10 μm.   
     
     
         3 . The electrode for electric-discharge surface treatment according to  claim 2 ,
 wherein powder, which includes not more than 3 vol % of powder having a particle diameter of not less than 20 μm, is selected as the hard material and the Si powder which have the average particle diameter of not more than 10 μm.   
     
     
         4 . The electrode for electric-discharge surface treatment according to  claim 1 ,
 wherein the Si powder is mixed to the electrode for electric-discharge surface treatment by 10 to 75 vol %.   
     
     
         5 . A method for forming an electrode for electric-discharge surface treatment, which is used in the electric-discharge surface treatment in which pulsed electric discharge is generated between the electrode and a base material in a machining fluid or in the air by using a green compact, which is formed by compressing powder of an electrode material, as the electrode, and by using energy of the electric discharge, a coating including the electrode material or a reaction product of the electrode material reacted by the electric discharge energy is formed on a surface of a base material,
 wherein Si powder is mixed to hard material powder while being crushed to obtain a mixed and crushed powder having an average particle diameter of not less than 0.3 μm and not more than 10 μm, and the mixed and crushed powder is compressed to form the electrode material.   
     
     
         6 . The method for forming the electrode for electric-discharge surface treatment according to  claim 5 ,
 wherein crushing is performed to the hard material and the Si powder which have the average particle diameter of not more than 10 μm until a percentage of powder having a particle diameter of not less than 20 μm is not more than 5 vol %.   
     
     
         7 . The method for forming the electrode for electric-discharge surface treatment according to  claim 6 ,
 wherein crushing is performed to the hard material and the Si powder which have the average particle diameter of not more than 10 μm until a percentage of powder having a particle diameter of not less than 20 μm is not more than 3 vol %.   
     
     
         8 . The method for forming the electrode for electric-discharge surface treatment according to  claim 5 ,
 wherein the Si powder is mixed to the hard material powder by 10 to 75 vol %.