Method for producing sintered body

A method for manufacturing a sintered body comprising:

• providing a metal powder, a binder, and an organic material, wherein said organic material acts as a lubricant;
• mixing and kneading said metal powder, said binder, and said organic material in order to produce a feed stock;
• introducing said feed stock to an extrusion machine, said extrusion machine having a hopper, a screw cylinder, and an extrusion die having an injection side die and an extrusion side die;
• heating said feed stock passing through said screw cylinder with a plurality of heaters on said screw cylinder to a first temperature above a melting point of said binder;
• extruding said feed stock within said extrusion die,
• wherein a first heater located on said injection side die maintains a second temperature substantially equal to said first temperature above said melting point of said binder during compaction of said feedstock, a second heater located on said extrusion side die lowers said feed stock to a third temperature less than said melting point of said binder, and an extrusion side cooling unit solidifies said feed stock to form an extruded body;
• debinding said extruded body;
• and
• sintering said debound extruded body so as to manufacture a sintered body;
• wherein the extrusion molding step is performed with an extrusion die temperature lower than the melting point of said binder but higher than the melting point of said organic material in the vicinity of an extrusion opening.

A method for manufacturing a sintered body comprising:

• providing a metal powder, a binder, and an organic material, wherein said organic material acts as a lubricant;
• mixing and kneading said metal powder, said binder, and said organic material in order to produce a feed stock, wherein said kneading is performed from 50° to 250° C., inclusive, and for 20 to 210 minutes, inclusive;
• introducing said feed stock to an extrusion machine, said extrusion machine having a hopper, a screw cylinder, and an extrusion die having an injection side die and an extrusion side die;
• heating said feed stock passing through said screw cylinder with a plurality of heaters on said screw cylinder to a first temperature of 100° C.-400° C., said first temperature is above a melting point of said binder;
• extruding said feed stock within said extrusion die, wherein a first heater located on said injection side die maintains a second temperature substantially equal to said first temperature, and a second heater in combination with an extrusion side cooling unit located on said extrusion side die cool said feed stock to a third temperature of 30° C.-120° C., said third temperature is lower than said melting point of said binder to form an extruded body;
• debinding said extruded body;
• and
• sintering said debound extruded body so as to manufacture a sintered body;
• wherein the extrusion molding step is performed with an extrusion side die temperature lower than the melting point of the binder but higher than the melting point of the organic material in the vicinity of an extrusion opening.

A method for manufacturing a sintered body comprising:

• extruding a feed stock with an extrusion machine, said feed stock including a metal powder, a binder, and an organic material, wherein said organic material acts as a lubricant,
• wherein said extruding of said feed stock includes:
• heating said feed stock to a first temperature with a plurality of heaters located on a cylinder of an extrusion machine;
• compacting said feed stock in an injection side of a die;
• heating said feed stock during said compacting of said feed stock to a first temperature with a first heater located on said injection side of said die;
• heating said feed stock to a second temperature with a second heater located on an extrusion side of said die;
• ejecting said feed stock from said extrusion side of said die;
• and
• cooling said feed stock during said ejecting of said feed stock with a cooling unit located on said extrusion side die to form an extruded body;
• debinding said extruded body;
• and
• sintering said extruded body to form said sintered body.