| 摘要 |
<p>Methods of forming a new wear and abrasion overlay (42) formed with the steel surfaces of components (41) for earth boring bits, and the components formed by the methods are disclosed. The overlay (42) comprises a hard material particulate (38) containing a metal carbide and an alloy steel matrix (44). The volume fraction of the hard material particulate (38) in the overlay is grater than about 75%, the average particle size of the hard material particulate (38) is between about 40 mesh and about 80 mesh, and the thickness of the overlay (42) is less than about 0.050 inches. The process of manufacture includes the steps of fixing a monolayer of hard material particulate (38) to the surface of a flexible mould (26), filling the mould with materials and powders (28), and CIP densifying to form a preform. The preform is then forged to near 100% density in a rapid solid state densification powder metallurgy process. The resulting bit component has an integrally formed overlay with superior physical properties. <IMAGE></p> |
