Method of making a porous sintered body, a compound for making the porous sintered body, and the porous sintered body

Abstract

A thermal formation sintering compound containing a binder, a sinterable powder material and a pore formation material, for formation into a predetermined shape in a thermal formation step, removal of the binder in a degreasing step, and sintering of the powder material in a sintering step is provided. The binder contains a low-temperature draining component which melts in the thermal formation step, begins draining at a temperature lower than a draining temperature of the pore formation material, and drains at a temperature lower than a temperature at which the pore formation material drains; and a high-temperature draining component which melts in the thermal formation step, begins draining after the pore formation material begins draining, and drains at a temperature higher than does the pore formation material.

What is claimed is: 
     
         1 . A thermal formation sintering compound containing a binder, a sinterable powder material and a pore formation material, for formation into a predetermined shape in a thermal formation step, removal of the binder in a degreasing step, and sintering of the powder material in a sintering step,
 wherein the binder contains: a low-temperature draining component which melts in the thermal formation step, begins draining at a temperature lower than a draining temperature of the pore formation material, and drains at a temperature lower than a temperature at which the pore formation material drains; and   a high-temperature draining component which melts in the thermal formation step, begins draining after the pore formation material begins draining, and drains at a temperature higher than does the pore formation material.   
     
     
         2 . The sintering compound according to  claim 1 , wherein the binder contains the low-temperature draining component at a rate of 40 volume percent through 70 volume percent. 
     
     
         3 . The sintering compound for a porous body according to  claim 1 , wherein the high-temperature draining component contains at least two binder components each draining at a draining temperature differing from that of the others, after the pore formation material has drained. 
     
     
         4 . The sintering compound for a porous body according to  claim 1 , containing the pore formation material at a rate of 50 through 80 volume percent of the sintering compound.