Endmills and method of making the same

Abstract

An endmill having a body formed from a single piece of material and having length greater than 1.6 inches and a method for forming such an endmill are provided. The method includes sintering a blank with an ultra hard material while in a heater having a length of at least 1.6 inches.

1 . A method for forming an end mill having polycrystalline ultra hard material comprising: 
 providing a blank having a groove;    placing an ultra hard material in the groove;    placing the blank in a refractory metal enclosure;    placing the enclosure in a heater, said heater having a length greater than 1.6 inch; and    pressing the heater with blank in a press while heating using said heater for sintering the ultra hard material in the groove forming a polycrystalline ultra hard material in the groove.    
     
     
         2 . The method as recited in  claim 1  wherein the heater has a length of about 2.5 inches.  
     
     
         3 . The method as recited in  claim 1  wherein providing a blank comprises providing a blank having a length of at least 1.6 inches.  
     
     
         4 . The method as recited in  claim 1  wherein the heater has a length greater than 1.7 inches wherein providing a blank comprises providing a blank having a length greater 1.7 inches.  
     
     
         5 . The method as recited in  claim 1  wherein the heater has a length greater than 1.75 inches wherein providing a blank comprises providing a blank having a length greater 1.75 inches.  
     
     
         6 . The method as recited in  claim 1  wherein the heater has a length of about 2 inches wherein providing a blank comprises providing a blank having a length no less than about 2 inches.  
     
     
         7 . The method as recited in  claim 1  wherein the blank is provided in powder form.  
     
     
         8 . The method as recited in  claim 1  further comprising machining the blank to form a flute having a cutting edge defined by the polycrystalline ultra hard material.  
     
     
         9 . The method as recited in  claim 1  wherein the press is selected from the group or presses consisting of belt presses and piston-cylinder presses.  
     
     
         10 . The method as recited in  claim 1  wherein the heater does not include end heating units at opposite ends thereof.  
     
     
         11 . A method for forming an end mill having polycrystalline ultra hard material comprising: 
 providing a blank having a length greater than 1.6 inches and a groove;    placing an ultra hard material in the groove;    placing the blank in a refractory metal enclosure;    placing the enclosure in a heater; and    pressing the heater in a press while heating using said heater for sintering the ultra hard material in the groove forming a polycrystalline ultra hard material in the groove.    
     
     
         12 . The method as recited in  claim 11  wherein providing a blank comprises providing a blank having a length greater than 1.7 inches.  
     
     
         13 . The method as recited in  claim 11  wherein providing a blank comprises providing a blank having a length greater than 1.75 inches.  
     
     
         14 . The method as recited in  claim 11  wherein providing a blank comprises providing a blank having a length of about 2 inches.  
     
     
         15 . The method as recited in  claim 11  further comprising machining the blank to form a flute having a cutting edge defined by the polycrystalline ultra hard material.  
     
     
         16 . The method as recited in  claim 11  wherein the press is selected from the group or presses consisting of belt presses and piston-cylinder presses.  
     
     
         17 . The method as recited in  claim 11  wherein the heater is elongate and does not include end heating units at opposite ends thereof.  
     
     
         18 . An endmill comprising: 
 a body having a length of at least 1.6 inches and comprising a grip portion, said body being formed from a single piece of material; and    polycrystalline ultra hard material bonded to the body.    
     
     
         19 . The endmill as recited in  claim 18  wherein the body comprises a length of at least 1.7 inches.  
     
     
         20 . The endmill as recited in  claim 18  wherein the body comprises a length of at least 1.75 inches.  
     
     
         21 . The endmill as recited in  claim 18  wherein the body comprises a length not less than 2 inches.  
     
     
         22 . The endmill as recited in  claim 18  wherein the polycrystalline ultra hard material does not extend to the grip portion.