Optimization of 5-Axis milling processes based on the process models with application to airfoil machining

5-axis milling is widely used in machining of complex surfaces such as airfoils. Improper selection of machining parameters may cause low productivity and undesired results during machining. There are several constraints such as available power and torque, chatter stability, tool breakage etc. In order to respect such constraints proper machining parameters should be determined. In this paper, methodologies for improving 5-axis milling processes are presented. Selection of machining parameters is performed using process simulations. The developed methodologies are presented on an example airfoil

Optimization of 5-axis milling processes using process models

Productivity and part quality are extremely important for all machining operations, but particularly for 5-axis milling where the machine tool cost is relatively higher, and most parts have complex geometries and high quality requirements with tight tolerances. 5- axis milling, presents additional challenges in modeling due to more complex tool and workpiece interface geometry, and process mechanics. In this paper, modeling and optimization of 5-axis processes with cutting strategy selection are presented. The developed process models are used for cutting force predictions using a part-tool interface identification method which is also presented. Based on the model predictions and simulations, best cutting conditions are identified. Also, for finish process of a complex surface, machining time is estimated using three machining strategy alternatives. Results are demonstrated by example applications, and verified by experiments

Process simulation for 5-axis machining using generalized milling tool geometries

Multi-axis machining (especially 5-axis machining) is widely used in precision machining for automotive, aerospace and die-mold manufacturing. The goal in precision machining is to increase production while meeting high part quality needs which can be achieved through decision of appropriate process parameters considering machine tool constraints (such as power and torque), chatter-free operations and part quality. In order to predict and decide on optimal process parameters, simulation models are used. In the literature, individual tool geometries for multi-axis machining are examined in detailed with different modeling approaches to simulate cutting forces. In this study, a general numerical model for 5-axis machining is proposed covering all possible tool geometries. Tool envelope is extracted from CAD data, and helical flutes points are represented in cylindrical coordinates. Equal parallel slicing method is utilized to find cutter engagement boundaries (CEB) determining cutting region of the tool surface. for each axial level in the tool axis direction. For each level uncut chip thickness value is found and total forces are calculated by summing force values for each point along the cutting flutes. For arbitrary cases forces are simulated and obtained results are experimentally verified

Tool orientation effects on the geometry of 5-axis ball-end milling

5-axis ball-end milling has found application in various industries especially for machining of parts with complex surfaces. Additional two degree of freedoms, namely, lead and tilt angles make it possible to machine complex parts by providing extra flexibility in cutting tool orientation. However, they also complicate the geometry of the process. Knowledge of the process geometry is important for understanding of 5-axis ball-end milling operations. Although there are considerable amount of work done in 3-axis milling, the literature on 5-axis ball-end milling is limited. Some of the terminology used in 3-axis milling is not directly applicable to 5-axis ball end-milling. Hence some new process parameters and coordinate systems are defined to represent a 5-axis ball end-milling process completely. The engagement zone between the cutting tool and the workpiece is more involved due to the effects of lead and tilt angles. In this paper, effects of these angles on the process geometry are explained by presenting CAD models and analytical calculations

Machining strategy development in 5-axis milling operations using process models

Increased productivity and part quality can be achieved by selecting machining strategies and conditions properly. At one extreme very high speed and feed rate with small depth of cut can be used for high productivity whereas deep cuts accompanied with slow speeds and feeds may also provide increased material removal rates in some cases. In this study, it is shown that process models are useful tools to simulate and compare alternative strategies for machining of a part. 5-axis milling of turbine engine compressors made out of titanium alloys is used as the case study where strategies such as flank milling (deep cuts), point milling (light cuts) and stripe milling (medium depths) are compared in terms of process time by considering chatter stability, surface finish and tool deflections

Modeling dynamics and stability of 5-axis milling processes

5-axis milling is an important machining process for several industries such as aero-space, automotive and die/mold. It is mainly used in machining of sculptured surfaces where surface quality is of extreme importance. Being one of the most important prob-lems in machining, chatter vibrations must be avoided in manufacturing of these com-ponents as they result in high cutting forces, poor surface finish and unacceptable part quality. Chatter free cutting conditions for required quality with higher productivity can be determined by using stability models. Up to now, dynamic milling and stability models have been developed for 3-axis milling operations; however the stability of 5-axis proc-esses has never been modeled. In this paper, a stability model for 5-axis milling opera-tions is proposed. The model can consider the 3D dynamics of the 5-axis milling proc-ess including effects of all important process parameters including lead and tilt angles. Due to the complex geometry and mechanics of the process, the resulting analytical equations are solved numerically in order to generate the stability diagrams

Quasistatic deflection analysis of slender ball-end milling cutter

This work was supported by the National Natural Science Foundation of China (Grant No. 51975333), Jinan University and Institute Innovation Team Program (Grant No. 2020GXRC025), and Taishan Scholars Project of Shandong Province (ts201712002).Peer reviewedPostprin

From computer-aided to intelligent machining: Recent advances in computer numerical control machining research

The aim of this paper is to provide an introduction and overview of recent advances in the key technologies and the supporting computerized systems, and to indicate the trend of research and development in the area of computational numerical control machining. Three main themes of recent research in CNC machining are simulation, optimization and automation, which form the key aspects of intelligent manufacturing in the digital and knowledge based manufacturing era. As the information and knowledge carrier, feature is the efficacious way to achieve intelligent manufacturing. From the regular shaped feature to freeform surface feature, the feature technology has been used in manufacturing of complex parts, such as aircraft structural parts. The authors’ latest research in intelligent machining is presented through a new concept of multi-perspective dynamic feature (MpDF), for future discussion and communication with readers of this special issue. The MpDF concept has been implemented and tested in real examples from the aerospace industry, and has the potential to make promising impact on the future research in the new paradigm of intelligent machining. The authors of this paper are the guest editors of this special issue on computational numerical control machining. The guest editors have extensive and complementary experiences in both academia and industry, gained in China, USA and UK