Powder metallurgical method

Abstract

A powder metallurgical method includes preparing a liquid lubricant by mixing ethylene bis stearamide 60 to 70 wt % and erucamide 30 to 40 wt % at 150 to 170° C. in a high temperature stirring process. A pulverized solid lubricant is prepared by cooling the liquid lubricant to form a solid and pulverizing the solid. A powder metallurgy composition is prepared by mixing the pulverized solid lubricant 0.4 to 0.75 part by weight to metal-based powder 100 parts by weight, and a molded body is prepared by compression molding of the powder metallurgy composition.

What is claimed is: 
     
         1 . A powder metallurgical method, comprising:
 preparing a liquid lubricant by mixing ethylene bis stearamide 60 to 70 wt % and erucamide 30 to 40 wt % at 150 to 170° C. in a high temperature stirring process;   preparing a pulverized solid lubricant by cooling the liquid lubricant to form a solid and pulverizing the solid;   preparing a powder metallurgy composition by mixing the pulverized solid lubricant 0.4 to 0.75 part by weight to metal-based powder 100 parts by weight; and   preparing a molded body by compression molding of the powder metallurgy composition.   
     
     
         2 . The powder metallurgical method of  claim 1 , wherein the metal-based powder is iron-based powder. 
     
     
         3 . The powder metallurgical method of  claim 1 , wherein the compression molding is conducted under a pressure of 500 to 600 MPa. 
     
     
         4 . The powder metallurgical method of  claim 1 , further comprising:
 ejecting the molded body from a mold by adding an ejection force of 900 to 1400 Kgf.   
     
     
         5 . The powder metallurgical method of  claim 1 ,
 wherein the step of preparing a molded body further comprises adding an ejection force of 900 to 1100 Kgf,   the compression molding is conducted under a pressure of 500 to 600 MPa,   and the molded body has a density of 7.2 to 7.3 g/cm 3 .