Effect of workpiece heat treatment on surface quality of AWJ kerf

Abrasive water jet (AWJ) technology have been widely used for machining, while most commercial applications are based on the injection abrasive water jet (injection AWJ) technology. Compared with injection AWJ, abrasive suspension jet (ASJ) has higher energy efficiency. Under the same system pressure, the material removal rate by ASJ is up to five times higher than that by injection AWJ. This paper studied the pressure variation characteristics of ASJ machining system. Two models were built to describe the boosting and decompression processes of ASJ system. The decompression time of ASJ system can be predicted with the model of decompression process. The model of boosting process can be used to predict the target maximum pressure and the time consumption of boosting process, which are two important factors that have significant effects on the machining efficiency. The boosting process of the ASJ system is very important for machining. The influence of the compressibility of water and the friction resistance of the hydraulic system on the pressure variation characteristics of ASJ system during the machining process was also discussed.

Abrasive waterjet (AWJ) cutting is the nontraditional cutting process which is capable of cutting variety of difficult-to-cut materials. However, this process experiences relatively greater initial investment, operating and tooling and maintenance costs. Therefore precise selection of the operating variables is very important for the commercial use of this process. Experiments were performed by changing water pressure, traverse speed, mass flow rate and standoff distance for cutting alumina ceramic production utilizing AWJ cutting technology. A persistent research and advancement exertion has been made to investigate its hidden science to build its machining execution and applications. To appropriately choose the procedure parameters, exact model for the forecast of profundity of cut in AWJ cutting of alumina ceramic production is built up utilizing dimensional and regression/relapse investigation techniques. This research work also evaluated the effect of parameters on profundity of cut which is a standout amongst the most huge cutting execution measures in AWJ cutting of alumina ceramics production. This established model has been affirmed with the trial outcomes that divulge a high pertinence of the model inside the exploratory range utilized.

Abrasive waterjet was found effective in cutting materials like glass, steel and aluminium for various industrial applications. The effect of process parameters on abrasive waterjet cutting (AWJC) of Al6061/SiC/Al2O3 composite was disclosed in the present work. The cutting parameters taken for study were traverse speed, abrasive flow rate, water pressure and stand-off distance. Surface roughness, kerf width and bevel angle of cut were observed as the quality characteristics for various cutting trials. Experiments were designed using Taguchi's L18 orthogonal array and an integrated technique of principal component based response surface methodology (PC-RSM) was disclosed for designing the parameters. Significant improvements were observed in the quality characteristics obtained with optimal parameter setting identified by PC-RSM approach. Abrasive waterjet parameters like water pressure, stand-off distance and the interaction between abrasive flow rate and traverse speed were found to be influential on the quality characteristics.

Abrasive waterjet (AWJ) micro-machining is a precision processing technology with some distinct advantages. To understand the machining process, the erosion mechanism is presented and discussed when micro-particle impacting on a quartz crystal specimen. It is found that three types of impressions are formed which are craters, micro-dents and scratches. Small-scale craters including crashed zones and radial cracks are associated with plastic flow and subsurface micro-cracks that decrease the material strength, but cause little material removal, while large-scale craters including conchoidal fractures caused by the propagation of lateral cracks dominate the volume change of the specimen. Micro-dents are produced by the impact of particles possessing small kinetic energies, and scratches are generated by particle sliding or rolling over the target surface and make a negligible contribution to material removal. The crater volume generated by the impact of individual particle is then discussed with respect to particle impacting velocity and impact angle. It shows that an increase in particle impact angle or particle velocity increases the crater volume due to the increased conchoidal fractures during the impact process.

Material removal and surface damage mechanisms in micro drilling of Nd:YAG material

On the mechanism and mechanics of material removal in ultrasonic machining

Experimental investigation and mechanism of material removal in nano finishing of MMCs using abrasive flow finishing (AFF) process

Abrasive water jet (AWJ) is one of the most advanced and valuable non-traditional machining processes because of its massive advantages of removing metals ranging from hard to soft. This paper focused on studying the influence of jet pressure, feed rate and standoff distance on surface roughness during cutting carbon steel using abrasive water jet cutting. A surface roughness device assessed the surface roughness by performing sixteen experiments to identify the distinct texture of the surface. Based on the experiences, the best surface roughness value was 3.14 μm at jet pressure 300 MPa, standoff distance 4mm and feed rate 30 mm/min. The Taguchi method was introduced to implement the experiments and indicate the most influential process parameters on average surface roughness. The experimental results reveal that feed rate has a significant effect on average surface roughness.

Surface Characterization, Material Removal Mechanism and Material Migration Study of Micro EDM Process on Conductive SiC

Toward achieving control over the kerfing through macro abrasive waterjet submerged milling, there is a need (i) to understand the influence of the water column height on the kerf quality and (ii) to develop a model for the prediction of the kerf characteristics. This study performs detailed experimentation to assess the kerf quality enhancement in submerged milling relative to the in-air milling on Al-6061 alloy. From the modeling perspective, there are very limited efforts in developing a comprehensive model that includes both the jet flow dynamics and material removal models—this is the missing link. Toward this, a comprehensive model is proposed and validated for the prediction of kerf in in-air and submerged conditions by considering (i) jet dynamics and (ii) jet–material interaction. From the experimental results, it is observed that by adopting the submerged milling, the damaged region, top kerf width and edge radius got reduced by 20.3%, 13.53%, and 22.7%, respectively. However, this enhancement in the kerf quality is associated with a reduction in the centerline erosion depth (hmax) by 12.33% and a material removal rate by 24.52%. The material removal mechanism is more uniform and directed in the submerged milling, whereas in-air is random. The proposed model predicted the kerf cross-sectional profile in submerged milling and in-air with a mean absolute error of 60 µm and 57 µm, squared Pearson correlation coefficient of 0.97 and 0.99, and the hmax with a maximum error of 1.3% and 1.4%.

Investigations into hard turning process using wiper tool inserts

Grinding characteristics, material removal and damage formation mechanisms in high removal rate grinding of silicon carbide

Mechanism of synergetic material removal by electrochemomechanical magnetorheological polishing

Material removal behavior in ultrasonic-assisted scratching of SiC ceramics with a single diamond tool

Material removal characteristics in submerged pulsating air jet polishing process