Cutting bit body and method for making the same

Abstract

A cutting bit body that is a part of a cutting bit that includes a hard insert that is affixed to the cutting bit body and wherein the cutting bit impinges earth strata. The cutting bit body is an elongate powder metallurgical body member. A method for making a powder metallurgical cutting bit body that includes the steps of: providing a powder mixture; pressing the powder mixture into a green cutting bit body compact having a partial density; and consolidating the green body to form the powder metallurgical cutting bit body.

1 . A cutting bit body for a cutting bit that comprises a hard insert affixed to the cutting bit body and wherein the cutting bit impinges earth strata, the cutting bit body comprises: an elongate powder metallurgical body member. 
     
     
         2 . The cutting bit body according to  claim 1  wherein the elongate powder metallurgical body member is formed by consolidating a green powder metallurgical compact. 
     
     
         3 . The cutting bit body according to  claim 1  wherein the elongate powder metallurgical body member is formed by removing material from a fully sintered powder metallurgical body. 
     
     
         4 . The cutting bit body according to  claim 1  wherein the elongate powder metallurgical body member is formed by deforming a fully sintered powder metallurgical body. 
     
     
         5 . The cutting bit body according to  claim 1  wherein the elongate powder metallurgical body member having a plurality of distinct regions. 
     
     
         6 . The cutting bit body according to  claim 1  wherein the elongate powder metallurgical body member comprises an iron-based alloy having at least about 30 weight percent iron. 
     
     
         7 . An earth cutting tool comprising a hard insert affixed to an elongate powder metallurgical body member. 
     
     
         8 . A cutting bit body for a cutting bit that comprises a hard insert affixed to the cutting bit body and wherein the cutting bit impinges earth strata, the cutting bit body comprises:
 a plurality of cutting bit body components;   at least one of the cutting bit body components being a powder metallurgical cutting bit body component formed by consolidating a green powder metallurgical compact comprising an iron-based alloy having at least about 30 weight percent iron;   at least one of the cutting bit body components being a conventionally-made cutting bit body component comprising an iron-based alloy having at least about 30 weight percent iron; and   the conventionally-made cutting bit body component is joined together to the powder metallurgical cutting bit body component.   
     
     
         9 . The cutting bit body according to  claim 8  wherein the powder metallurgical cutting bit body component is formed by removing material from a fully sintered powder metallurgical body. 
     
     
         10 . The cutting bit body according to  claim 8  wherein the powder metallurgical cutting bit body component is formed by deforming a fully sintered powder metallurgical body. 
     
     
         11 . The cutting bit body according to  claim 8  wherein a plurality of the cutting bit body components being powder metallurgical components. 
     
     
         13 . A cutting bit for impinging on earth strata that comprises:
 a hard insert affixed to a cutting bit body, and the cutting bit body comprises:   a plurality of cutting bit body components;   at least one of the cutting bit body components being a powder metallurgical cutting bit body component formed by consolidating a green powder metallurgical compact comprising an iron-based alloy having at least about 30 weight percent iron;   at least one of the cutting bit body components being a conventionally-made cutting bit body component comprising an iron-based alloy having at least about 30 weight percent iron; and   the conventionally-made cutting bit body component is joined together to the powder metallurgical cutting bit body component.   
     
     
         14 . The cutting bit according to  claim 13  wherein the powder metallurgical cutting bit body component is formed by removing material from a fully sintered powder metallurgical body. 
     
     
         15 . The cutting bit according to  claim 13  wherein the powder metallurgical cutting bit body component is formed by deforming a fully sintered powder metallurgical body. 
     
     
         16 . The cutting bit according to  claim 13  wherein a plurality of the cutting bit body components being powder metallurgical components. 
     
     
         17 . A method for making a powder metallurgical cutting bit body comprising the steps of:
 providing a powder mixture;   pressing the powder mixture into a green cutting bit body compact having a partial density; and   consolidating the green body to form the powder metallurgical cutting bit body.   
     
     
         18 . The method according to  claim 17  wherein the consolidating step occurs under heat. 
     
     
         19 . The method according to  claim 17  wherein the consolidating step occurs under heat and pressure. 
     
     
         20 . The method according to  claim 17  wherein the powder mixture comprises an iron-based alloy having at least about 30 weight percent iron.