Preform structure and method of manufacturing preform and bearing housing structure having the preform formed into metal matrix composite of cylinder block

Abstract

When a cylinder block is cast, a bearing housing is constituted by a preform integrally cast with the cylinder block. In order to raise the strength of the bearing housing, a metal matrix composite is formed around the preform. The preform is constituted by a high volume factor member having a relatively high volume factor and two low volume factor members having a relatively low volume factor connected with top and under surfaces of the high volume factor member respectively. The high volume factor member is made of solid metal and the low volume factor member is made of sintered metal filaments. Base material of the cylinder block infiltrates into the low volume factor member to form a metal matrix composite in the preform.

What is claimed is:  
     
         1 . A preform for forming a metal matrix composite, comprising: 
 a high volume factor member having a relatively high volume factor; and    a low volume factor member having a relatively low volume factor connected with said high volume factor member.    
     
     
         2 . The preform according to  claim 1 , wherein said high volume factor member is made of solid metal and said low volume factor member is made of metal filaments.  
     
     
         3 . The preform according to  claim 1 , wherein said high volume factor member is formed into a plate configuration and said high volume factor member is interleaved between said two low volume factor members.  
     
     
         4 . A method of manufacturing a preform for forming a metal matrix composite, at least comprising the steps of: 
 laminating at least a low volume factor member having a relatively low volume factor on a high volume factor member having a relatively high volume factor; and    sintering said low volume factor member superimposed on said high volume factor member.    
     
     
         5 . A method of manufacturing a preform for forming a metal matrix composite, comprising the steps of: 
 weaving metal filaments to make a metal filament web;    punching out said metal filament web into a plurality of small webs;    laminating said small webs into a laminated web block;    pressing said laminated web block;    sintering said laminated web block to complete a low volume factor member having a relatively low volume factor;    interleaving a high volume factor member having a relatively high volume factor between said low volume factor members; and    sintering said high volume factor member and said low volume factor member in an interleaving manner between said low volume factor members.    
     
     
         6 . A bearing housing structure for supporting a shaft, comprising: 
 a metal matrix composite formed in a preform.    
     
     
         7 . The bearing housing structure according to  claim 6 , wherein said preform is manufactured by a method comprising the steps of: 
 laminating at least a low volume factor member having a relatively low volume factor on a high volume factor member having a relatively high volume factor; and    sintering said low volume factor member superimposed on said high volume factor member.    
     
     
         8 . The bearing housing structure according to  claim 6 , wherein said preform is manufactured by a method comprising the steps of: 
 weaving metal filaments to make a metal filament web;    punching out said metal filament web into a plurality of small webs;    laminating said small webs into a laminated web block;    pressing said laminated web block;    sintering said laminated web block to complete a low volume factor member having a relatively low volume factor;    interleaving a high volume factor member having a relatively high volume factor between said low volume factor members; and    sintering said high volume factor member and said low volume factor member in an interleaving manner between said low volume factor members.    
     
     
         9 . The bearing housing structure according to  claim 6 , wherein said metal matrix composite is formed by integrally casting base material with said preform.  
     
     
         10 . A bearing housing structure provided in a cylinder block for supporting a crankshaft, comprising: 
 a metal matrix composite formed in a preform.    
     
     
         11 . The bearing housing structure according to  claim 10 , wherein said preform is manufactured by a method comprising the steps of: 
 laminating at least a low volume factor member having a relatively low volume factor on a high volume factor member having a relatively high volume factor; and    sintering said low volume factor member superimposed on said high volume factor member.    
     
     
         12 . The bearing housing structure according to  claim 10 , wherein said preform is manufactured by a method comprising the steps of: 
 weaving metal filaments to make a metal filament web;    punching out said metal filament web into a plurality of small webs;    laminating said small webs into a laminated web block;    pressing said laminated web block;    sintering said laminated web block to complete a low volume factor member having a relatively low volume factor;    interleaving a high volume factor member having a relatively high volume factor between said low volume factor members; and    sintering said high volume factor member and said low volume factor member in an interleaving manner between said low volume factor members.    
     
     
         13 . The bearing housing structure according to  claim 10 , wherein said metal matrix composite is formed by integrally casting base material with said preform.