Extrusion die for metallic material

Abstract

In some preferred, embodiments, an extrusion die for a metallic material capable of obtaining a high quality extruded article can be provide while securing sufficient strength and durability. The die is provided with a male die case 20 having a pressure receiving portion 21 , a female die case 25 , a male die 30 provided in the male die case 20 , and a female die 40 provided in the female die case 25 . The pressure receiving portion 21 is formed into a convex configuration protruded rearward, and a porthole for introducing a metallic material is formed in the external periphery of the pressure receiving portion. A press-fitting connecting portion 21 a is formed at the front side of the male die case 20 and a press-fitting dented portion 25 a is formed at the rear side of the female die case 25 . The press-fitting connecting portion 21 a is fitted in the press-fitting dented portion 25 a to thereby connect both the die cases 20 and 25 with the male die case 20 restrained from its periphery thereof by the female die case 25.

1 . An extrusion die for a metallic material, comprising:
 a male die case having a pressure receiving portion with an external surface constituting a metallic material pressure receiving surface, the male die case being disposed with the pressure receiving portion facing rearward against an extrusion direction of the metallic material;   a female die case disposed at a front side of the male die case:   a male die provided in the male die case; and   a female die provided in the female die case to form an extrusion hole by and between the female die and the male die,   wherein the metallic material pressure receiving surface of the pressure receiving portion is formed into a convex configuration protruded rearward, and a porthole for introducing the metallic material is formed in an external periphery of the pressure receiving portion,   wherein a press-fitting connecting portion is formed at a front side external periphery of the male die case, and a press-fitting dented portion is formed at a rear side external periphery of the female die case, and   wherein the press-fitting connecting portion is press-fitted in the press-fitting dented portion, whereby both the die cases are connected with each other with the male die case restrained from periphery thereof by the female die case.   
   
   
       2 . The extrusion die for a metallic material as recited in  claim 1 , wherein an axis of the porthole is disposed so as to incline with respect to an axis of the male die case so that the axis of the porthole approaches the axis of the male die case toward a downstream side. 
   
   
       3 . The extrusion die for a metallic material as recited in  claim 1  or  2 , wherein a radius direction compression rate (press-fitting margin) of the press-fitting connecting portion with respect to the press-fitting dented portion is set to 1 to 8%. 
   
   
       4 . The extrusion die for a metallic material as recited in any one of  claims 1  to  3 , wherein the male die case and the male die are formed separately, and the male die is held by the male die case. 
   
   
       5 . The extrusion die for a metallic material as recited in any one of  claims 1  to  3 , wherein the male die is integrally formed to the male die case. 
   
   
       6 . The extrusion die for a metallic material as recited in any one of  claims 1  to  5 , wherein the female die is integrally formed to the female die case. 
   
   
       7 . The extrusion die for a metallic material as recited in any one of  claims 1  to  6 , wherein a flow control plate for controlling a metallic material flow is integrally formed to the male die case. 
   
   
       8 . The extrusion die for a metallic material as recited in any one of  claims 1  to  7 , wherein the pressure receiving portion is formed into a semi-spherical configuration. 
   
   
       9 . The extrusion die for a metallic material as recited in any one of  claims 1  to  7 , wherein the metallic material pressure receiving surface is constituted by a convex spherical surface of a ⅙ to 4/6 sphere. 
   
   
       10 . The extrusion die for a metallic material as recited in any one of  claims 1  to  7 , wherein the pressure receiving portion is formed into a polyhedral configuration in which a plurality of side surfaces are disposed on the pressure receiving surface. 
   
   
       11 . The extrusion die for a metallic material as recited in any one of  claims 1  to  7 , wherein the pressure receiving portion is formed to have an elliptical or oval configuration as seen from an axial direction of the male die case. 
   
   
       12 . The extrusion die for a metallic material as recited in any one of  claims 1  to  7 , wherein a protrusion dimension of the pressure receiving portion along an axial direction of the male die case is set to be longer than a radius dimension of the pressure receiving portion along a direction perpendicular to the axial direction, and wherein the pressure receiving portion is formed to have a semi-elliptical or semi-oval configuration as seen from a direction perpendicular to the axial direction. 
   
   
       13 . The extrusion die for a metallic material as recited in any one of  claims 1  to  12 , wherein the male die case has a plurality of the portholes arranged at equal intervals in a peripheral direction around an axis of the male die case. 
   
   
       14 . The extrusion die for a metallic material as recited in  claim 2 , wherein an inclination angle of the axis of the porthole is set to 3 to 35° with respect to the axis of the male die case. 
   
   
       15 . The extrusion die for a metallic material as recited in any one of  claims 1  to  14 , wherein the metallic material is aluminum or aluminum alloy. 
   
   
       16 . The extrusion die for a metallic material as recited in any one of  claims 1  to  15 , wherein a circular extrusion hole is formed by and between the male die and the female die so that the metallic material is extruded through the extrusion hole to form a tubular member circular in cross-section. 
   
   
       17 . The extrusion die for a metallic material as recited in any one of  claims 1  to  15 ,
 wherein an extrusion hole having a flat circular cross-sectional configuration with a height (thickness) smaller than a width is formed by the male die and the female die,   wherein a portion of the male die corresponding to the extrusion hole is formed into a comb-line configuration having a plurality of passage forming protrusions arranged in a width direction, and   wherein the metallic material passes through the extrusion hole to form a multi-bored hollow extruded member having a plurality of passages arranged in a width direction.   
   
   
       18 . An extruded article production method for producing an extruded article by using the extrusion die as recited in any one of  claims 1  to  15 . 
   
   
       19 . An extruded tubular member production method for producing an extruded tubular member by using the extrusion die as recited in  claim 16 . 
   
   
       20 . A multi-bored hollow member production method for producing a multi-bored hollow member by using the extrusion die as recited in  claim 17 . 
   
   
       21 . A die case for en extrusion die, comprising:
 a male die case having a pressure receiving portion with an external surface constituting a metallic material pressure receiving surface, the male die case being disposed with the pressure receiving portion facing rearward against an extrusion direction of the metallic material, and a male die being provided in the male die case; and   a female die case disposed at a front side of the male die case, a female die being provided in the female die case,   wherein the metallic material pressure receiving surface of the pressure receiving portion is formed into a convex configuration protruded rearward, and a porthole for introducing the metallic material is formed in an external periphery of the pressure receiving portion,   wherein a press-fitting connecting portion is formed at a front side external periphery of the male die case, and a press-fitting dented portion is formed at a rear side external periphery of the female die case, and   wherein the press-fitting connecting portion is press-fitted in the press-fitting dented portion, whereby both the die cases are connected with each other with the male die case restrained from periphery thereof by the female die case.   
   
   
       22 . The die case for an extrusion die as recited in  claim 21 , wherein the metallic material pressure receiving surface is constituted by a convex spherical surface of a ⅙ to 4/6 sphere. 
   
   
       23 . A metallic material extrusion method, comprising the steps of:
 preparing a male die case having a pressure receiving portion with an external surface constituting a metallic material pressure receiving surface, the male die case being disposed with the pressure receiving portion facing rearward against an extrusion direction of the metallic material, a female die case disposed at a front side of the male die case, a male die provided in the male die case, and a female die provided in the female die case to form an extrusion hole by and between the male die and the female die;   forming a porthole for introducing a metallic material in an external periphery of the pressure receiving portion having a convex configuration constituting the metallic material pressure receiving surface protruded rearward;   forming a press-fitting connecting portion at a front side external periphery of the male die case and forming a press-fitting dented portion at a rear side external periphery of the female die case;   connecting both the die cases with the male die case restrained from its periphery thereof by the female die case by press-fitting the press-fitting connecting portion into the press-fitting dented portion; and   introducing the metallic material pressed against the metallic material pressure receiving surface in both the die cases via the porthole with both the die cases connected to thereby pass through the extrusion hole.   
   
   
       24 . A metallic material extruder comprising a container and an extrusion die set in the container, the extruder being configured to supply a metallic material in the container to the extrusion die,
 wherein the extrusion die comprises:   a male die case having a pressure receiving portion with an external surface constituting a metallic material pressure receiving surface, the male die case being disposed with the pressure receiving portion facing rearward against an extrusion direction of the metallic material;   a female die case disposed at a front side of the male die case;   a male die provided in the male die case; and   a female die provided in the female die case to form an extrusion hole by and between the male die and the female die,   wherein the metallic material pressure receiving surface of the pressure receiving portion is formed into a convex configuration protruded rearward, and a porthole for introducing the metallic material is formed in an external periphery of the pressure receiving portion,   wherein a press-fitting connecting portion is formed at a front side external periphery of the male die case and a press-fitting dented portion is formed at a rear side external periphery of the female die case,   wherein both the die cases are connected with each other with the male die case restrained from its periphery thereof by the female die case by press-fitting the press-fitting connecting portion into the press-fitting dented portion, and   wherein the metallic material pressed against the metallic material pressure receiving surface is introduced in both the die cases via the porthole to thereby pass through the extrusion hole.