Study on Generating Machining Performance of Two-Dimensional Ultrasonic Vibration-Composited Electrolysis/Electro-Discharge Technology for MMCs

Ultrasonic vibration-composited electrolysis/electro-discharge machining technology (UE/DM) is effective for machining particulate-reinforced metal matrix composites (MMCs). However, the vibration of the tool or workpiece suitable for holes limits the application of UE/DM. To improve the generating machining efficiency and quality of flat and curved surfaces, in this study, we implemented two-dimensional ultrasonic vibration into UE/DM and constructed a novel method named two-dimensional ultrasonic vibration-composited electrolysis/electro-discharge machining (2UE/DM). The influence of vibration on the performance of 2UE/DM compared to other process technologies was studied, and an orthogonal experiment was designed to optimize the parameters. The results indicated that the materiel remove rate (MRR) mainly increased via voltage and tool vibration. The change current was responsible for the MRR in the process. Spindle speed and workpiece vibration were not dominant factors affecting the MRR; the spindle speed and tool and workpiece vibration, which reduced the height difference between a ridge and crater caused by abrasive grinding, were responsible for surface roughness (Ra) and form precision (δ). Additionally, the optimized parameters of 1000 rpm, 3 V, and 5 um were conducted on MMCs of 40 SiCp/Al and achieved the maximum MRR and minimum Ra and δ of 0.76 mm3/min, 3.35 um, and 5.84%, respectively. This study’s findings provide valuable process parameters for improving machining efficiency and quality for MMCs of 2UE/DM.

Recent Patents on Mechanical Structure of 3D Printer

Background: 3D printing technology is widely applied in transportation, industrial equipment, medical, aerospace, and civil industry due to its characteristics of material saving, no model manufacturing, and machinability of complex parts. The mechanical structure of 3D printer mainly includes 3D printer head structure and working platform and plays a major role in the machining efficiency and processing accuracy of the 3D printer. Thus, increasingly attention has been paid to the current trends of the mechanical structure of 3D printers. Objective: To meet the increasing requirements of 3D printing processing efficiency and precision, the mechanical structure of 3D printers, such as 3D print head structure and working platform, needs to be carefully studied, and a feasible mechanical structure of 3D printers should be proposed. Methods: This paper studies various representative patent related to the mechanical structure of 3D printer, analyzes the mechanical structure of 3D printer, and studies the perfect mechanical structure of 3D printer. Results: Through summarizing a lot of patents about the mechanical structure of 3D printers, the main current existing problems such as platform jitter and machining error are summarized and analyzed, a new mechanical structure of 3D printers is proposed. Moreover, the development tendency of the mechanical structure of 3D printers in the future is discussed. Conclusion: The optimization of the mechanical structure of 3D printer is conducive to increasing the machining efficiency and processing accuracy in the 3D printing process. More relevant patents about working platform and 3D printer head will be invented in the future

Fabrication of Microgrooves by Synchronous Hybrid Laser and Shaped Tube Electrochemical Milling

The fabrication of deep microgrooves has become an issue that needs to be addressed with the introduction of difficult-to-cut materials and ever-increasing stringent quality requirements. However, both laser machining and electrochemical machining could not fulfill the requirements of high machining efficiency and precision with good surface quality. In this paper, laser and shaped tube electrochemical milling (Laser-STEM) were initially employed to fabricate microgrooves. The mechanisms of the Laser-STEM process were studied theoretically and experimentally. With the developed experimental setup, the influences of laser power and voltage on the width, depth and bottom surface roughness of the fabricated microgrooves were studied. Results have shown a laser power of less than 6 W could enhance the electrochemical machining rate without forming a deep kerf at the bottom during Laser-STEM. The machining accuracy or localization of electrochemicals could be improved with laser assistance, whilst the laser with a high-power density would deteriorate the surface roughness of the bottom machining area. Experimental results have proved that both the machining efficiency and the machining precision can be enhanced by synchronous laser-assisted STEM, compared with that of pure electrochemical milling. The machining side gap was decreased by 62.5% while using a laser power of 6 W in Laser-STEM. The laser-assistance effects were beneficial to reduce the surface roughness of the microgrooves machined by Laser-STEM, with the proper voltage. A laser power of 3 W was preferred to obtain the smallest surface roughness value. Additionally, the machining efficiency of layer-by-layer Laser-STEM can be improved utilizing a constant layer thickness (CLT) mode, while fabricating microgrooves with a high aspect ratio. Finally, microgrooves with a width of 1.79 mm, a depth of 6.49 mm and a surface roughness of 2.5 μm were successfully fabricated.

Review On Preceding And Perspective Research In Electrochemical Discharge Machining

Electrochemical discharge machining is an adaptable machining measure for miniature boring, miniature finishing, and miniature cutting of an assortment of glasses, ceramics, and composites. Electrochemical discharge machining (ECDM), otherwise called flash-assisted compound etching, is a successful miniature machining measure for non-leading materials. It has appeal in Micro Electro Mechanical System (MEMS) applications. Electrochemical discharge machining has ended up being a productive miniature machining measure and altogether utilized for the machining of non-conductive materials. Electro Chemical Discharge Machining (ECDM) is a controlled metal-evacuation measure that is utilized in metal elimination through electric flash disintegration. Because of advancements in technology, the scaled-down products have gained advantages in Lab-on-a-chip devices, including micro-electromechanical frameworks. Electrochemical discharge machining has done a good job of generating miniature openings and channels on electrically non-conductive materials, and it has emerged as a potential competitor. This paper examines the state of craftsmanship in various areas of electrochemical discharge machining, including the workpiece, electrolyte, hardware terminal behavior, gas film arrangement, machining efficiency, and late hybridizations in electrochemical discharge machining. The conclusion focuses on or summarizes potential exploration trends for improving ECDM proficiency also addresses machining issues.

Research on machining parameter optimization in finishing milling with multiple constraints

High efficiency and high precision milling, as the eternal goal of CNC machining, needs to balance many constraints for selecting the most reasonable processing parameters. This paper presents an efficient machining parameter optimization method for finishing milling operation with multiple constraints. Firstly, under the multiple constraints of parameter feasible region, milling force, milling stability, roughness, and machining contour accuracy, a multi-variable parameter optimization model with machining efficiency as the objective is established. A four level cycle optimization strategy has been detailly described for solving the optimization problem, in which the feed per tooth is optimized by using the golden section method, and with the aid of the random vector search method, the spindle speed, radial, and axial depth cuts are both numerically iterated. The optimal machining parameter combination of the tooth number, feed per tooth, spindle speed, radial, and axial depth of cuts are achieved at last. Finally, the experimental verification results show that the proposed method can greatly improve the machining efficiency under chatter free condition and achieve an efficient finishing milling with consideration of the multiple constraints.

B-spline based corner smoothing method to decrease the maximum curvature of the transition curve

Toolpath represented by linear segments leads to tangency discontinuity between blocks, which results in fluctuation of feedrate and reduction of machining efficiency and quality. To eliminate these unwanted external factors, optimal corner smoothing operation is essential for CNC systems to achieve a smooth toolpath. This work proposes a corner smoothing approach by generating a B-spline transition curve with 7 control points. By adjusting the position of the control points, the resulting transition curve is not limited to smooth the corner in the convex side of the corner, but shuttles back and forth between the convex and concave sides to decrease the maximum curvature, while respecting the given error tolerance. The approximation errors in convex and concave sides can be analytically calculated. Experimental results demonstrate the effectiveness of the proposed method on machining efficiency improvement.

A corner smoothing algorithm using Trajectory Pattern Method (TPM) for high-speed and high-quality machining

In micro-line segments machining, transition curves with high harmonic components are more prone to causing vibration issues in the feed drive system, which affects machining efficiency and quality severely. To construct low harmonic trajectories, this paper proposes a corner smoothing algorithm that uses the Trajectory Pattern Method (TPM). The transition curve construction and axial motion scheduling are performed with a specified fundamental frequency in one step, which reduces the smoothing process time and avoids excitation of natural modes of vibration of the system. The synthesized trajectories and axial kinematic profiles are all smooth and only contain the selected fundamental frequency and its first two odd harmonics, which minimizes the number of high harmonic components in the required actuation forces/torques and avoids excitation of the system modes of vibration. Linear programming is used to synthesize the trajectories. The proposed algorithm is shown to achieve near time-optimal trajectories. The provided experimental analysis and comparisons demonstrate that the proposed algorithm achieves smooth axial kinematic profiles with low harmonic contents, which would improve machining efficiency and quality.

Recent Patents on A Discharge State Detection of EDM

Background: Electrical discharge machining (EDM) has been widely applied in manufacturing high strength and high hardness of mental material due to no mechanical forces in the EDM process. The discharge state, a vital process parameter of EDM, directly affects the machining quality and machining efficiency. So, it is necessary to detect the real-time discharge state of EDM. Therefore, discharge state detection of EDM at present has been paid more and more attention. Objective: The methods for discharge state detection of EDM are being improved continuously to meet the increasing requirement of machining quality and machining efficiency in the EDM process. Methods: This paper reviews various representative patents related to the methods for discharge state detection of EDM. Results: By summarizing numerous patents about the methods for discharge state detection of EDM, the main problems such as low detection accuracy and long delay time of discharge state detection of EDM are summarized and analyzed. In addition, the further development of the discharge state detection method of EDM is discussed. Conclusion: The optimization of methods for discharge state detection is conducive to improving machining quality and machining efficiency in the EDM process. Moreover, more relevant patents will be invented in the future.