Surface Integrity Evaluation of Brass CW614N after Impact of Acoustically Excited Pulsating Water Jet

AbstractPresented article is focused on surface integrity evaluation of brass CW614N form the sight of surface topography, structural changes in surface layers and strengthening character in subsurface layers after impact of acoustically excited pulsating water jet (PWJ). Surface topography was evaluated using optical profilometry. Structural changes in subsurface layer were observed based on mass material removal Δm [mg/s] and maximal depth of penetrance of PWJ hmax [mm]. Nano indentation measurement according to Berkovich were used to examination of strengthening character in subsurface layer. Disintegration of experimental samples was performed under constant technological conditions: hydraulic power of plunger pump Ph = 19kW; round nozzle diameter d = 1.6mm; feed speed rate v = 0.75mm/s; pressure of plunger pump p = 38MPa, stand-off distance of nozzle from target material z = 45mm; ultrasound frequency f = 20.29kHz and as variable factor was set power of ultrasound P on values 340, 360 and 380W. In terms of surface topography experimental investigation proved that PWJ under selected conditions is not suitable for precision machining. Evaluation of the surface characteristics indicates that the chemical composition has a significant effect on material weight loss Δm [mg/s] and a maximum depth of penetration of PWJ hmax [mm]. Evaluation of characteristics of subsurface layer was observed strengthened area with lower elasticity

Abrasive waterjet (AWJ) titanium tangential turning evaluation

The paper deals with abrasive waterjet titanium tangential turning. Titanium grade 3 with a diameter of 55 mm was used as an experimental material. Technological conditions of turning tests were the same by gradually changing value of traverse speed (vf = 1,5; 3; 4,5; 6; 7,5 mm·min-1). Experiment tests were performed by using continuous abrasive waterjet of pressure p = 400MPa, by rotation n = 60 rpm of workpiece. The abrasive particles (Barton Garnet) were fed to the waterjet in the amount of 0,4 kg·min-1. It was determined that acceleration of traverse speed did not increase the surface profile parameters.Web of Science53454053

Hydroabrasive disintegration of rotating Monel K-500 workpiece

This paper addresses the hydroabrasive disintegration of the difficult-to-machine material, Monel K-500. An experiment was performed using a hydroabrasive cutting system with an additional rotating module. The objective of the preliminary experiments was to identify significant technological factors and investigate their impact on the machined surface quality of difficult-to-machine materials. To describe the impact of parameters, experiments were carried out according to the design of experiment. Surface roughness parameters were measured, and surface topography visualisation and analysis were conducted. The results concluded that the abrasive mass flow rate and traverse speed significantly influence the surface roughness and material removal rate. From a practical point of view, the technology can prepare semi-finished workpiece shapes; however, surface finishing is necessary.Web of Science961-4100198

Evaluation of physical phenomena and surface integrity during hydroabrasive disintegration of the rotating workpiece with feedback loop control

The paper deals with the potential of employing accompanying physical phenomena, acoustic emissions, during monitoring of abrasive water jet disintegration of rotating workpiece. It focuses on the acquisition of theoretical knowledge about this technology with the aid of SEM surface analysis. Variation in traverse speed of the cutting head is used during the experiments. All values were obtained during experimental materials turning by AWJ method. The surfaces were scanned using optical profilometer MicroProf FRT to obtain surface roughness parameters such as Ra (10.75 mu m-22.5 mu m), Rq (13.75 mu m-28.25 mu m) and Rz (88 mu m-166 mu m). The result includes the possibility of on-line control in the form of an adaptive connection, which applies information gathered by an array of sensors and its transformation into a digital form. The acquired signals represent that with increase in traverse speed, the signal intensities decrease due to shorter interaction time. SEM images provide characteristics of surfaces created by HADRO process such as craters, peaks and valleys, micro-cracks and striations marks.Web of Science13459458

Tangential turning of Incoloy alloy 925 using abrasive water jet technology

The paper deals with tangential abrasive water jet (AWJ) turning of Incoloy alloy 925. The aim of the experiment was to analyze the impact of the AWJ traverse speed (1.5– 9 mm/min) on the surface quality in terms of micro-structure formed on the created surface. The water pressure was set to 400 MPa and the spindle revolution to 34 rpm. Australian garnet (MESH 80) was used as an abrasive component. The surfaces were visualized and qualitatively described using a laser confocal microscope. Basic roughness parameters of the surfaces (Ra, Rq, Rz) were measured using an optical profilometer. The presented experimental results demonstrate that the technology of abrasive water jet turning is an appropriate tool for rough machining of difficult-to-machine materials.Web of Science829-121752174