Strike tip for a pick tool

Abstract

A strike tip for a pick tool is provided. The strike tip comprises a strike structure comprising a super-hard material and a substrate comprising cemented carbide material, the substrate being joined to the strike structure at an interface. The strike tip has rotational symmetry about a main central axis. The strike structure has a planar apex area and, on a plane on which the main central axis lies, a convex curved side wall extends between the planar apex area and the substrate.

1 . A strike tip for a pick tool, comprising:
 a strike structure comprising a super-hard material;   a substrate comprising cemented carbide material, the substrate being joined to the strike structure at an interface;   the strike tip having rotational symmetry about a main central axis, the strike structure having a planar apex area and, on a plane on which the main central axis lies, a convex curved side wall extending between the planar apex area and the substrate.   
     
     
         2 . The strike tip according to  claim 1 , wherein the curved side wall has a varying radius of curvature. 
     
     
         3 . The strike tip according to  claim 1 , wherein the planar apex area is 0.5 to 30 percent of a maximum area of a cross-section of the substrate. 
     
     
         4 . The strike tip according to  claim 1 , wherein the apex area is substantially circular, centred upon a central longitudinal axis of the strike tip. 
     
     
         5 . The strike tip according to  claim 1 , wherein the strike structure comprises a skirt structure depending from and surrounding the apex area. 
     
     
         6 . The strike tip according to  claim 5 , wherein the strike structure comprises a truncated conical surface arranged concentrically with the planar apex area. 
     
     
         7 . A strike tip according to  claim 1 , in which the super-hard material comprises polycrystalline diamond (PCD) material. 
     
     
         8 . A strike tip according to  claim 1 , wherein the thickness of the strike structure between the apex area and the interface opposite the apex is between 2.5 and 10 millimetres. 
     
     
         9 . An assembly for a pick tool for road milling or mining, comprising a strike tip as claimed in  claim 1 . 
     
     
         10 . A method of making a strike tip as claimed in  claim 1 , the method including
 providing a pre-cursor construction comprising a strike structure comprising a super-hard material and a substrate comprising cemented carbide material, the substrate being joined to the strike structure at an interface, the strike structure having a non-planar apex and a convex curved side wall depending from the planar apex area towards the substrate; and   processing the super-hard structure to remove a volume of the super-hard structure including the non-planar apex, such that the super-hard structure comprises a planar apex area.   
     
     
         11 . The method as according to  claim 10 , in which the non-planar apex of the pre-cursor construction is spherically rounded. 
     
     
         12 . The method according to  claim 10 , further comprising processing the super-hard structure to remove a volume of the super-hard structure including the non-planar apex to leave a planar apex area having an area of 0.5 to 30 percent of a maximum area of a cross-section of the substrate. 
     
     
         13 . The method according to  claim 10 , further comprising processing the super-hard structure to remove a volume of the super-hard structure including the non-planar apex to leave a planar apex area that is substantially circular and centred upon a central longitudinal axis of the strike tip.