Effects of erodent flow energy and local exposure time on the erosion of cement-based composites at high-speed hydro-abrasive flow

The objective of the paper is the quantification of effects of erodent flow kinetic energy and exposure time on the erosion of cement-based composites with high-speed hydro-abrasive jets. The erodent flow kinetic energy is varied due to changes in erodent velocity, traverse rate and erodent particle mass-flow rate. For a given traverse rate, the relationship between volumetric erosion rate and erodent flow kinetic energy follows a power function with power exponents between 0.49 and 0.66. The kinetic energy of the erodent flow is not a sufficient measure for the material removal capacity of high-speed hydro-abrasive flow. A critical exposure time must be realized in order to eliminate traverse rate effects. Exposure time effects are characterized with a Weibull-type function, whereby the shape parameter k of the function depends on erosion mode and material response. If incremental erosion modes dominate the material removal process: k>1. If continuous erosion modes control the material removal process: k≤1. It is supposed that k exceeds unity if a threshold fracture toughness of the composites is exceeded.