Experimental investigation on the effect of wear flat inclination on the cutting response of a blunt tool in rock cutting

Autor: Brian Evans, Iman Rostamsowlat, Thomas Richard
Rok vydání: 2018
Předmět:
Zdroj: Acta Geotechnica. 14:519-534
ISSN: 1861-1133
1861-1125
Popis: A vast majority of experimental researches focuses on the cutting action of a sharp cutter, while there has been limited experimental work devoted to the study of the contact process at the wear flat-rock interface. The specific objective of this study is to determine the effect of the wear flat inclination angle ( $$\beta$$ ) with respect to the cutter velocity vector ( $$\varvec{v}$$ ) on both the contact stress ( $$\sigma$$ ) and friction coefficient ( $$\mu$$ ) mobilized at the wear flat-rock interface. An extensive and comprehensive set of cutting experiments was carried out on thirteen different sedimentary quarry rock samples using a state-of-the-art rock cutting equipment. A unique cutter holder was purposely designed and manufactured along with a precise experimental protocol implemented in order to change the back rake angle and therefore the inclination $$\beta$$ by steps of $$0.10^{\circ }$$ . The experimental observations confirm the existence of three regimes of frictional contact (identified as elastic, elasto-plastic and plastic) for all rock samples. Further, the results suggest that the scaled contact stress is predominantly controlled by a dimensionless number $$\eta =\frac{E^{*}\tan \beta }{q}$$ with $$E^{*}$$ the plane strain elastic modulus and q the rock strength.
Databáze: OpenAIRE