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Double-arc milling cutter can effectively enhance the workpiece surface quality and is appropriate for finish machining complex surface. This article examines the effects of tool structure factor, two vertical milling orientations, workpiece inclination angle, cutting speed, and feed per tooth on the cutting force in order to thoroughly explore the cutting performance of double-arc milling cutter. Instantaneous effective cutting speed and radius models are established for various cutting orientations and conditions using the parameterized model of double-arc milling cutter. Additionally, a method for characterizing the tool structure factor of double-arc milling cutter is proposed. Three double-arc milling cutters with different structure factor and single factor experiments for milling concave and convex surfaces are designed. The impact of tool structure factor, workpiece inclination angle, cutting orientations, and cutting parameters on cutting force is thoroughly analyzed. Theoretical support is provided for the optimization of tool parameters, cutting orientations, and cutting parameters prior to surface machining. [ABSTRACT FROM AUTHOR]

Aiming at the problems of uneven illumination at the edge of the surface damage image of the face milling cutter, the blade line at the damage cannot be accurately identified, and the slow recognition rate of the traditional image processing technology, an on-machine accurate measurement method for the surface damage of the face milling cutter, is proposed. The industrial camera, lens, and adjustable LED ring lighting are placed on the camera support, and they are used to collect the image of the flank face of the face milling cutter. This method first divides the tool damage area into the tool wear bright zone area and the damaged edge missing area and selects the specific tool position area for template matching. Next, the tool damage area is extracted, the arc fitting method is used to fit the missing area of the broken edge, the edge curve is reshaped, and the improved sub-pixel edge detection method is used to extract the lower boundary of the tool wear bright zone area. The cutting edge curve of the damaged area and the lower boundary edge curve of the wear area are spliced to obtain the tool damage area, and finally, the maximum damage width value of the tool flank is calculated. The on-machine detection platform is built to carry out the milling experiment of the face milling cutter. The damage value extracted by this method is compared with the damage value measured by the super depth of field microscope. The average difference in the tool damage value is within 3%. The results show that the proposed method can effectively detect tool damage under the premise of ensuring efficiency on-line and in-process and provides an effective solution for the condition monitoring of face milling cutter in actual machining. [ABSTRACT FROM AUTHOR]

There are inequable force-induced deformation, obvious cutting vibration problems during side milling of low-rigidity frame and beam parts, resulting in unsatisfactory dimensional accuracy and surface quality. Most of these parts are side-milled by end mill, which currently in use do not take into account the workpiece stiffness imparity. Therefore, the concept of gradient helix edge (GHE) is proposed in this research, and its advantages are analyzed. The general mathematical model is given. Furthermore, the parabola is taken as an example for the GHE space equation derived, of which accuracy is verified by numerical simulation. Finally, the comparison experiment with the invariant helix edge end mill was completed. The results showed that the milling force perpendicular to the milling surface of the GHE end mill was smaller and with less fluctuation, which could obtain less force-induced deformation theoretically. The milling process was smoother, and better surface quality was obtained. The excellent performance of the GHE end mill was further verified by milling different features. [ABSTRACT FROM AUTHOR]

The secondary development can realize the integration of commercial CAD and CAM/CAE software and has been widely used in the design of cutting tools. However, with the development of cutting tools design towards system integration, the integration effect cannot meet the needs of current tool design due to factors such as kernel and interface. Based on the independent semi open source modeling kernel Open CASCADE, this paper realizes the parametric design of solid end mills. The parametric design system of solid end mills is established by using Python as the underlying language and Python OCC. The system can generate data files, 2D drawings, and 3D models conforming to ISO 13399 standard and realize the cloud storage function of model data. The generated tool model data can be used for finite element simulation of cutting process, NC programming, and guiding tool manufacturing. Based on the established system, the centroid optimization of the imbalance characteristics of the variable pitch and variable helix end mill is carried out, which improves the dynamic balance of this type of cutter and provides an important reference value for the design of this type of cutter. [ABSTRACT FROM AUTHOR]

Featured Application: This research is beneficial to manufacturing applications. With the increasing complexity of the workpiece surfaces in aerospace and automotive molding and other areas, an increasing number of cutting tools with different shapes and performance have become necessary. A new kind of cutting tool is developed with a double-arc revolving surface at the tool's end to improve the processing quality in numerical control milling, referred to as a double-arc cutting tool (DACT) in this paper. The parametric geometric model of the DACT is established. Three types of cutting-edge curves are proposed (a cutting edge with a constant helix angle, a cutting edge with a constant pitch, and an orthogonal spiral cutting edge). Corresponding numerical simulation results are also provided as graphical representations. A DACT is manufactured and tested to verify its feasibility. Finally, two contrast experiments are conducted to prove that DACT has a higher processing quality than a ball-end mill (BEM). The advantage of the DACT is verified, which provides a theoretical basis for higher quality machining. The parametric design and application research provides a new method and theoretical basis for other new types of cutting tools. [ABSTRACT FROM AUTHOR]

The performance of metal cutting tools directly affects the manufacturing efficiency and machining quality of products. With the increasing demands in manufacturing industry of cutting performance, machining efficiency, customization, and quick response, traditional tool design methods can no longer meet the above requirements due to many repetitive work, large amount of calculation, complex process, and low efficiency. Parametric design has become a new development direction of customized tool design because of its fast, stable, and accurate characteristics. Based on the parametric design of cutting tools, this paper develops a tool parametric design platform by using the method of secondary development of commercial CAD software. The platform realizes automatic operation in the background without commercial CAD software interface, completes the parametric modeling process of tools, generates 2D drawings and 3D models conforming to ISO 13399 standard, and realizes the cloud storage function of model data and the parametric design of many kinds of tools. Compare with that traditional modeling method, using this parametric modeling platform, the modeling efficiency is increased by 90% on average. This platform is of great significance to improve the design efficiency of complex customized tools and shorten the original design cycle by 30%. [ABSTRACT FROM AUTHOR]

In order to study the correlation between parameters and performance indicators in the cutting process, the importance of different parameters in performance indicators should be determined. In the present study, the side milling process of titanium alloy by the end milling cutter is considered the research object, and analytic hierarchy process and grey-fuzzy evaluation method are used to evaluate the importance of tool geometric parameters and operating parameters on tool wear rate and material removal rate obtained by FEM method. It is found that applying the average method to remove the parameter level makes each parameter achieve the same result. Therefore, this method should be combined with other data processing methods to resolve the above problem. Finally, the range analysis method is applied to obtain the optimal parameter level of different parameters for each performance indicator. The obtained results show that the helix angle has the highest overall importance value, followed by feed per tooth. And the optimum combination of parameters for tool wear rate and material removal rate is obtained respectively. [ABSTRACT FROM AUTHOR]

Milling is a kind of interrupted cutting. When the tool cuts into the workpiece, it is often accompanied by instantaneous impact, which results in impact vibration of the milling system. Meanwhile, tool wear will occur gradually on flank face with the cutting progress. The impact vibration and tool wear affect the morphological characteristics of machined surfaces. In the present work, the instantaneous impact force is obtained by introducing the italic impact model of single degree of freedom, and the free vibration in the x and y directions under the impact force is obtained by combining the damped vibration equation. The cutting vibration in the x and y directions is obtained by solving the dynamic equation of the milling system with the fourth-order Runge–Kutta method. The equation of the cutting edge is modified according to the tool flank wear, and the machined surface topography considering the dynamic characteristics of cutting system and tool flank wear is obtained by combining the Z-MAP algorithm. The verification milling experiment was carried out on the hardened steel Cr12MoV workpiece. The simulation results are in good agreement with the experimental results. The research results have important guiding significance for the reasonable selection of processing parameters in actual production. [ABSTRACT FROM AUTHOR]

This paper proposes a kind of milling chatter stability prediction method used for the stability of milling free-form surface based on the time-domain. Firstly, a dynamic equation is established by considering the influence of mold surface curvature and cutting tool lead angle on dynamic chip thickness without deformation. Then, the multi-delay milling system vibration displacement, which is given by the ratio of dynamic chip thickness and the static chip thickness as the threshold, was calculated based on the numerical method. Finally, the chatter stability domain based on the full-discretization method of milling chatter stability domain is compared to analyze the influence of the characteristics of free surface curvature on the chatter stability domain. The results of the experiment show that the time-domain simulation method can reveal the influence of different processing areas of free-form surface mold on the instability mechanism of the system. The change trend of milling chatter stability domain was found to be consistent with the experimental results. [ABSTRACT FROM AUTHOR]

In the process of metal cutting, the cutting performance of cutting tools varies with different parameter combinations, so the results of the performance indicators studied are also different. So in order to achieve the best performance indicator it is necessary to get the best parameter matching combination. In addition, in the process of metal cutting, the value of the performance index is different at each stage of the processing process. In order to consider the cutting process more comprehensively, it is necessary to use a comprehensive evaluation method that can evaluate the dynamic process of performance indicators. This paper uses a dynamic evaluation method that considers the dynamic change of performance indicators in each stage of the cutting process to comprehensively evaluate the tool parameters and cutting parameters at each level. For the purpose of high processing efficiency and long tool life, tool wear rate and material removal rate are used as performance indicators. In the case of specified rake angle, cutting speed and cutting width, titanium alloy is studied by end milling cutter side milling. The tool parameters and cutting parameters in milling process are optimized by using a dynamic comprehensive evaluation method based on gain horizontal excitation. Finally, the parameter matching combination that can make the performance indicator reach the best is obtained. The results show that when the rake angle is 8°, the cutting speed is 37.68 m/min, and the cutting width is 0.2 mm, the tool wear rate and material removal rate are the best when the clearance angle is 9°, the helix angle is 30°, the feed per tooth is 0.15 mm/z, and the cutting depth is 2.5 mm. [ABSTRACT FROM AUTHOR]

Tool condition monitoring (TCM) in machining operations is crucial to maximise the useful tool life while reducing the risks associated with tool breakage. Unlike progressive tool wear, tool breakage occurs randomly, with more severe implications for workpiece quality, machining system stiffness, and even operator safety. Existing literature reviews on TCM focus on tool wear monitoring, including wear state recognition and remaining useful life prediction. However, a comprehensive review of tool breakage monitoring (TBM) techniques is lacking. Generic signal processing and intelligent decision-making methods cannot fully satisfy the practical requirements of the TBM. In addition, developing and evaluating TBM models using imbalanced data is more challenging. Herein, we present the first systematic review on TBM to bridge these limitations, and provide adequate guidance for avoiding catastrophic tool failures during cutting processes. Signal acquisition, feature extraction, and decision-making methodologies for the TBM are outlined and compared with related techniques for tool wear monitoring. The effects of data imbalance on TBM models are considered, and feasible solutions are provided at the data and algorithm levels. Finally, the challenges faced by the TBM are discussed, and potential research directions are suggested. The research and application of TBM techniques will certainly better empower various machining operations in response to intelligent manufacturing demands. [Display omitted] • Tool breakage monitoring techniques in machining operations are systematically reviewed. • The difference between tool wear and breakage monitoring are compared. • TBM data imbalance problems are discussed at the data and algorithm levels. • The performance metrics commonly used to evaluate TBM models are highlighted. • The specific research route of tool life cycle management is proposed. [ABSTRACT FROM AUTHOR]