Grader blade with casting/insert assembly on leading edge

摘要

A grader blade has a steel body with a bottom edge incorporating a substrate of air-hardened tool steel casting material assembling a preformed cemented carbide insert in tiered relationship with, and rearwardly of, a casted layer of carbide grit. The front casted carbide grit layer is formed in the casting operation and the rear preformed cemented carbide insert is arranged in the tiered contacting and attached relationship with the carbide grit layer as the latter is casted with the substrate of special steel casting that holds the insert and layer together. The steel body of the blade also includes a recess formed in and along the forward portion of the blade bottom edge into which the casted asembly is disposed and welded to the blade. The front casted layer of carbide grit is tougher than the rear preformed carbide insert making it better able to absorb impacts thereon, whereas the rear insert is composed of a cemented carbide composition having a low cobalt content, for instance ten percent by weight, adapting it for enhanced downpressure wear resistance.