Investigation of the worn surfaces of diamond sawblades in sawing granite

Abstract

The worn surfaces of the diamond segments in circular saws for the sawing of granite have been investigated. A scanning electron microscope and a toolmaker's microscope were used to examine the worn surfaces and radial sawblade wear during sawing was measured. Experimental results indicate that for the sawing of a hard South Africa red granite, the worn particles occurring on the segment surface are mainly of the macro-fractured crystal and/or pull-out hole type, making the sawblade cut less efficient. When cutting a relatively soft pink granite, the resulting worn particles produce a greater proportion of whole crystal and micro-fractured grit on the worn surface and the amount of crystal pull-out is also high, which causes the sawblade to cut efficiently during sawing. Further, in order to obtain the optimum blade performance, the diamond breakdown and the pull-out of the sawblade must operate in the correct wear mode.