A microscopic study on kerfs in rocks subjected to abrasive waterjet cutting

摘要

The aim of the present study is to identify details of the mechanisms of rock disaggregation caused by AWJ cutting. Experimental studies were performed to investigate the effects of AWJ on the cutting process of four types of rocks and to evaluate the influence of their properties on the AWJ removal mechanisms. In addition to SEM analysis, petrography was performed to characterize the kerfs generated by the AWJ. The results show that the removal mechanisms and thus the efficiency of cutting strongly depend on the rock types and their microstructures. Distinct patterns of kerfs were observed for hard-to-machine rocks and non-hard-to-machine rocks. However, these patterns are not necessarily explained by the same rock features. In some situations, high cutting rates may depend more on the impact action of the jet (e.g. quartz sandstone) or the erosion capacity of the jet (e. g. marble).