New EDM Generator Used for the Machining of 1.2363 and 1.2343ESR Steels

The basic building block of any electric discharge machine is a generator, which ensures the operation of material separation itself. Not only the erosion rate and electricity consumption but also the quality of the machined surfaces depend on the design of the generator. These key factors for efficient machining have been investigated using a new energy-saving and powerful generator developed for the electric discharge machine (EDM) while machining 1.2363 and 1.2343ESR steels. In order to monitor and model the responses in the form of eroding rate and surface quality, a two-level half-factor experiment was performed with one replication at the corner points and two replications at the central points, for a total of 80 rounds. Both graphite and copper electrodes of sizes 10x10 mm and 100x100 mm were used for eroding and the influence of parameter settings: Open-voltage, Pulse current, Pulse on-time and Pulse off-time was monitored. It was found out that the shape of the electrode and Pulse current have the most significant effect on the erosion rate. The parameters Pulse current, Pulse on-time and their mutual interaction have the most significant effect on the surface topography. Statistically significant factors influencing the occurrence of defects turned out to be Pulse current, Pulse on-time and Material of workpiece, where it can be seen that the material 1.2343ESR is significantly less prone to the formation of surface defects.

Effect of Input Parameters on SR and MRR for Tool Steel AISI L2 By Electric Discharge Machine (EDM)

Electric discharge machine (EDM) or may be call electric spark machine is one of the most important cutting process or manufacturing process because it gives high accurate dimension and can be produced the most complex shape. In this present material removal rate and surface roughness for tool steel AISI L2 studied. The input parametric for this process is current, pulse on time (Ton) and pulse off time (Toff).A full factorial method is used to formulate machine parameters and find the optimal process parameters of an electric spark. The result shows that the Surface roughness increasing with increasing current and pulse on time is increases while no effect by increase in pulse off time. Best surface roughness when using low current and pulse in time. The material removal rate is increasing with increasing in current and pulse on time while decreasing when pulse of time is increased. The experimented and predicted values by using Minilab17 software ​​of this process are approximately equal.

Glide path enlargement of curved molar canals using HyFlex EDM glide path file versus PathFile: a comparative study of preparation time and postoperative pain

Background This randomized clinical trial aimed to compare the preparation time and severity of postoperative pain between HyFlex Electric Discharge Machine (EDM) glide path file (GPF) and PathFile. Methods Eighty patients whose molar teeth had at least one severely curved canal were treated by the same specialist. After access cavity preparation, the patients were randomly assigned to receive glide path enlargement with either HyFlex EDM GPF or PathFile. ProTaper Next X1 and X2 files were used to prepare the canals. The time of preparation was assessed and the severity of postoperative pain over the next 7 days was recorded. The preparation time and the postoperative pain scores were compared using the Linear Mixed Models (P ≤ 0.05). Results Glide path enlargement time was significantly shorter with HyFlex EDM GPF (27.828 ± 2.345 s) than with PathFile (48.942 ± 2.864 s) (P < 0.001). The highest postoperative pain score was recorded on the first day and the pain decreased over time in both groups. HyFlex EDM GPF group patients reported significantly less postoperative pain than PathFile group patients overall (P < 0.001). Conclusions Postoperative pain and glide path preparation time could be reduced by using HyFlex EDM GPF system. Trial registration PKUSSNCT, PKUSSNCT-17B12, Registered 24 October 2017.

Glide Path Enlargement of Curved Molar Canals Using HyFlex EDM Glide Path File versus PathFile: A Comparative Study of Preparation Time and Postoperative Pain

Background: This randomized clinical trial aimed to compare the preparation time and severity of postoperative pain between the HyFlex Electric Discharge Machine (EDM) Glide Path File (GPF) and PathFile. Methods: Eighty patients whose molar teeth had at least one severely curved canal were treated by the same specialist. After access cavity preparation, the patients were randomly assigned to receive glide path enlargement with either HyFlex EDM GPF or PathFile. ProTaper Next X1 and X2 files were used to prepare the canals. The time of preparation was assessed and the severity of postoperative pain over the next 7 days was recorded. The preparation time and the postoperative pain scores were compared using one-way analysis of variance (ANOVA) (P ≤ 0.05).Results: Glide path enlargement time was significantly shorter with HyFlex EDM GPF (27.828 ± 2.345 sec) than with PathFile (48.942 ± 2.864 sec) (P < 0.001). The highest postoperative pain score was recorded on the first day and the pain decreased over time in both groups. HyFlex EDM GPF group patients reported significantly less postoperative pain than PathFile group patients overall (P < 0.05). Conclusion: Postoperative pain and glide path preparation time could be reduced by using the HyFlex EDM GPF system.Trial registration: PKUSSNCT, PKUSSNCT-17B12, Registered 24 October 2017

Development of Proportional–Integrative–Derivative (PID) Optimized for the MicroElectric Discharge Machine Fabrication of Nano-Bismuth Colloid

Metal nanoparticles are typically prepared by using a chemical method, and a suspension is added to control the particle size and concentration of the nanoparticles. In this study, a micro-electric discharge machine (micro-EDM) was used to melt bismuth into nanoparticles, thus yielding a colloidal solution. No chemicals were added during the manufacturing process, and pure water was used as the medium. The colloid was assessed using an electrohydraulic system, and process parameters were adjusted for optimization; additionally, the discharge pulse wave was analyzed. The proposed preparation process is simple, fast, and cost-effective; moreover, the manufacturing process allows for mass production and reduces environmental pollution. Experimental results revealed that the nano-bismuth (nano-bi) colloidal solution was successfully prepared by the micro-EDM, and absorption peaks in the UV-vis spectrum were observed at 234 and 237 nm. Moreover, to optimize the proportional–integral–derivative (PID) control parameters to be used in the micro-EDM to prepare the nano-bi colloidal solution, this study derived a mathematical model of the micro-EDM. MATLAB was used to obtain the PID parameters. The discharge success rate (74.1876%) for the nano-bi colloidal solution prepared using our method was higher than that (46.9196%) obtained for a nano-bi colloidal solution prepared using an online adaptation method.