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Severe plastic deformation (SPD) processing techniques are applied to polycrystalline metallic materials in order to refine the grain size up to the sub-micrometre or nanometer level. The decrease in grain size to a sub-micrometre level is related to beneficial mechanical properties such as very high strength. The most widely applied SPD method is equal-channel angular pressing (ECAP). In distinction to traditional cold rolling or drawing, SPD techniques frequently employ cyclic strain paths that can lead to an essentially unchanged shape of the material sample after processing. In this paper, multi-axis compression is applied by using the MAXStrain (R) unit to impose cyclic compression in two mutually orthogonal directions. This study is aimed to realize the evolution of microstructure and mechanical properties of AlMg5Si2Mn aluminium cast alloy subjected to multi-axis compression. The microstructure of the alloy in the as-cast and as deformed state was characterized by light and scanning electron microscopy. The results reveal that multi-axis compression has a great influence on the evolution of microstructure and final mechanical properties. The enhanced mechanical properties are associated with the progressive formation of refined microstructure which is heterogeneously distributed across the sample.

Vibration assisted machining (VAM) is a method that is widely used in improving the performance of machined products. External vibrations with high frequency to ultrasonic range along with an meso-micrometer amplitude are given to the cutting tool or workpiece. This will result in a periodic separation phenomenon, hence reducing the cutting force which has positive impacts on increasing tool life and machined surface quality. Among the high-precision machining processes, micro-milling which has the ability to produce complex components with 2D and 3D features, can also be applied with the vibration assisted method, known as vibration assisted micro-milling (VAMM). Based on the direction of vibration given in the machining process, there are 1D VAMM with linear vibrations and 2D VAMM with circular or elliptical trajectory vibrations. However to date, neither developed 1D nor 2D VAMM systems are still limited to the research of planar surfaces cutting using linear movement axes, meanwhile vibration assisted in inclination cutting of micro-milling using the rotational movement axes is still very rare. Therefore the purpose of this paper is to present the preliminary model in designing a 2D VAMM system for a 5-axis micro-milling machine. The system is powered using piezoelectric actuators as the vibration-producing actuators.

In this paper, a velocity connection algorithm of arbitrary multi-axis linkage is presented with regard to the problem of velocity connection efficiency of multiple straight-line paths in the motion control system. For this algorithm, with the velocity, acceleration and displacement of the current segment and the previous segment as constraint conditions, the acceleration is not set as a constant but the intersegmental velocity variable is set independently. The initial velocity and final velocity of each segment is solved on this basis, improving the movement efficiency and simplifying the calculation. Therefore, this algorithm is particularly suitable for the high-speed movement mechanism driven by a stepper motor. As for the actual motion track of the rapid prototyping machine, a comparison was made between this algorithm and the traditional velocity connection algorithm to verify the effectiveness of this algorithm.

Multi-axis ball end milling experiments of H13 die steel have been conducted with four different cutter postures, and the 3D topographies of machined surfaces are acquired by optical profiler. The multi-scale analysis is carried out on the machined surfaces based on 2D dual-tree complex wavelet transform (2D DT-CWT). The topographies are decomposed into different frequency bands, and the roughness in every frequency band is calculated. The results reveal that the roughnesses of the machined surfaces under different cutter postures are quite different, the roughness is the lowest when the lead angle is 12° and the tilt angle is-22°. The roughnesses under different cutter postures exhibit similar changing trend with the variation of frequency bands: the roughnesses in the high and low frequency bands are relatively lower, the roughnesses in the medium frequency bands are higher. The 2D DT-CWT provides an ideal comprehensive topography analysis method for performance evaluation of machined surfaces.

With the development of China's manufacturing industry, the multi axis NC Machining Technology is rapidly popular. In the case of impeller shaft processing, this paper introduces the NC machining method and of three axial impeller based on Cimatron software, It is important practical significance and reference value to realize multi axis machining by the three axis CNC equipment.

This paper presents an effective rule-based method for extracting and recognizing the machining features from 3D solid model. The machining feature is automatically recognized while considering the relationship between machining feature and machining process. This proposed method is capable of recognizing not only prismatic machining features but also multi-axis machining features from many kinds of complex design features in both protrusion and depression. It also succeeds in recognizing various types of interaction in a uniform way. The capability of the proposed method is demonstrated in one specific case study.

We present a multi-axis motor speed control system based on the communication technology of FP-X PLC and VF0C inverter. The method is that change the three-phase input frequency of the motor to control the motor via the inverters. This paper presents PLC and inverters communication technology are used in electric drive systems, and explores PLC sent the commands to the inverters via the touchscreen and the RS485 port and write data to the drive to change its system parameters and output frequency to control the speed and state of the motor.

Interpolation calculation is the main performance assessment indicators in CNC system. In this paper, a self-designed multi-axis jewelry lathe is used as an experiment platform and the workpiece is a kind of silver or gold ellipsoidal ball with thin wall.According to the basic requirements of the algorithm, the structural characteristics of the machine tool and the special characteristics of the shape of the workpiece , a new interpolation algorithm named spacial ellipsoid helix interpolation is proposed and studied.

Based on the analysis of the demand in the manufacturing industry for multi-axis CNC (Computerized Numerical Control) machining technicians with high quality, the quality characteristics of the technicians are elaborated initially in this paper. Afterwards, the current situation and the problems existed in technician cultivation of multi-axis CNC machining in vocational colleges are analyzed. Solutions are proposed finally: enhance the construction of instructors, improve training equipments, enrich teaching resources and teach hierarchically.

Combined with the requirements for multi-axis CNC machining technicians in manufacturing industry, the current situation and problems existed in CNC multi-axis machining teaching are analyzed initially in this paper. Afterwards, in order to solve these problems and achieve theoretical teaching and skills training purposes, the advantages of CNC simulation software are applied in CNC multi-axis machining teaching. Finally, the deficiencies of the CNC simulation software are discussed so as to avoid in teaching.

This paper discovers the dynamic modeling process based on equilibrium condition of forces and moments, in order to improve handling stability, the side-slip angle need to be reduced to zero, special process is used in the dynamic equations simplification for demanded theoretical steering angle of each axel. At last this systems steady-resonance characteristics are researched.

To realize the online error analysis and verification of control strategy, it is necessary to simulate the states of the motion mechanism, and accurately to obtain the motion relationship between multi-axis and between motors. So a test and simulation system of multi-axis controller was designed. The system consists of a unit of real-time acquisition and analysis, a simulation unit of motor loads, a motherboard and a computer. Motor driving signals for multi channels are synchronously sampled and analyzed by the unit of acquisition and analysis. Motherboard is used to link the various parts. The working states of motor divers under loads are simulated by simulating the motor loads. In the industrial computer, the control effects of multi-axis control system are displayed by 3D simulation. Test results show that the system is stable and reliable, and has a certain application value.

This paper presents a method to simultaneously increase the accuracy and decrease the calculation time for complex tool path programming in multi-axis machining centers. Examples of complex parts requiring such complex tool paths include various kinds of turbine blades, pump-forcing augers, teeth surfaces, etc. It explains the creation of topological structures on the basis of analytical spline curves with floating range definitions. The method for tool path calculation accommodates the specific requirements for multi-axis milling. The algorithms developed are the foundation for the CAD/CAM software that allows for NC programming and machining on 5-axis centers employing any design model. Industrial tests reveal a 70-80% reduction of NC programming time of parts with complex surfaces, reduced machining time of approximately 40-50% using basic high-speed cutting methods and custom-made tools. The advanced methods of NC programming result in substantially increasing machining accuracy.

Cutter-workpiece engagement (CWE) is the contact zone where the cutting flutes enter and exit the workpiece as a function of axial depth of cut. Determination of CWE is the basis for predictions of cutting forces, machining error and chatter stability in multi-axis milling. In this paper, a solid modeling approach is developed to extract CWE for multi-axis milling by means of removal volume, which is obtained by subtracting analytic tool swept volume from in-process workpiece. Meanwhile, the feasible contact surfaces are used to trim the removal volume in order to determine CWE surfaces. Simulations are also performed to confirm the validity of the proposed method.

In this paper, by using the method of Lagrange equation mechanics, a 3DOF common dynamic differential equation for four-axis wheeled vehicle is calculated. whats more, a basic handling math model of four-axis wheeled vehicle is obtained. The handling performance and stability simulation for two plans of one type of vehicle is finished by using the model completed, and the suggestion for optimal design plan is given. According to the test data of sample vehicle that has been validated, the model has a high credibility.

This paper of simulation studying is mainly aiming for the typical part of multi-axis processing cylindrical cam by analyzing design drawings and technical requirements of processing, planning NC processing technology, creating cylindrical cam model and importing NC program to VERICUT simulation software. In this way, simulation of the entire machining process could be observed clearly.

The important characteristic of modern technological engineering is the systemic approach through unification and typification of problems related to production processes and equipment. The multi-criterial analysis of solutions and connections is difficult under the conditions in which the accelerated generalization of technological innovation determines sometimes an exaggerated diversification of constructive variants. Our researches, presented in this paper, provide original solutions for the development and organisation of modular structures in a computerized data base, the elaboration and use of a new method to automatically configure and reconfigure them using a computer programme. In this way we obtained the optimal variant to construct and operate completely modularized adjustable multi-spindle ends.

In order to improve multi-axis machine accuracy, error compensation techniques have been widely applied. However, the lack of reliable methods for direct, global and comprehensive estimation implies that all compensation techniques are based on off-line sequential error components measurement. These measurements provide static results, and cannot reflect the actual machine conditions. Thus, these results are not representative of the real working conditions because of disturbances from thermal distortions and dynamic perturbations. This paper presents an on-line error identification and compensation approach for CNC multi-axis machine tools. Based on the simultaneous measurement of error components, the proposed identification scheme is built to ensure volumetric error prediction for an adaptive error compensation system. Implemented on a moving bridge type CMM, the approach led to a significant improvement of the three-dimensional measurement accuracy.Compared to the conventional off-line error compensation techniques, the proposed identification and compensation approach can further improve the compensation adaptability and efficiency.

This paper presents an investigation of the vibration control performance of a nonlinear damper system under multi-axis excitations, focusing on its optimum strategy. The nonlinear damper system is composed of a particle damper and a primary structure. Cross-correlation functions and auto-correlation functions are shown to be suitable means to interpret the physics involved in the behavior of such a nonlinear system. Using different types of random excitations, the optimum operating regions are all determined, within which particles move in a plug flow pattern and correlation functions decay much faster than that under the inefficient operating conditions.

Binocular and parallel plate structure load cells are very successful designs for strain based measurements of shear loads. In this paper we use finite element methods (FEM) to investigate the suitability of these two load cell designs for use in a force plate and compare the sensitivity of these two force plates to that of the Heglund’s force plate. Each force plate is also sensitive to two moments with axis in the same plane as the force plate. If the force plate is to be used as a two component force-moment sensor, we determine which moment axis is best to use. Finally, a novel six-axis load cell is modelled by assembling three force plates together with rotational symmetry. The sensitivity of the six-axis load cell is calculated using FEM. Analysis of the six axis load cell predicts good measurement sensitivity and isotropy while maintaining low interference between measurement axes. Further benefits of the load cell design are discussed.

According to the analysis of a flexible tooling platform, this paper realized the overall design of the control system for the flexible tooling platform, introduced the compound of the control system and operation principle in detail, realized the design of PC control software based on Visual C++ and CATIA secondary development technology, completed the design of the servo system and the RS-485 control system network and set up a completed flexible tooling platform control system.

This paper describes an interpolation algorithm in the multi-axis motion control system, which can achieve six-axis interpolation operations, greatly improving the processing efficiency. Using modular design idea on the Quartus II platform, by DDA interpolation theory, interpolation modules are built through VHDL. And these interpolator modules are connected into schematic diagrams. By those schematic diagrams a linear interpolator, a circular interpolator and a composite interpolator are formed. The corresponding functions of those interpolators have been simulated on the Quartus II platform. The simulation shows that this interpolation algorithm is effective to complex multi-axis motion control system.

We design a rapid positioning multi-axis and multi-blade saw machine in order to meet the processing needs of outer ply of engineered wood flooring and wood shutters in China. The machine uses two sets of saws against cutting in the cutting width, so its saw blade is thin, cutting loss is small and cut-turn percentage is high. Meanwhile, it has the feature of rapid positioning, convenient operation and high precision machining, which provides ideal processing equipment for China sheet production.

Now, the complication and systemization of the industry is increasing day after day, which make it hard to design the motion control system. However, the technology of field control is increasing, and the motion control system based on the network is widely used. The company of beck Hoff introduced the Ether CAT network, which can be configured easily, and the speed of communication is high, and in some way, the technology has become the focus of the studying the automation. This paper analyst the application for the Ether CAT in the multi-axis motion control system.

In this paper, a design system combining clinical experience and engineering knowledge was developed for the manufacture of custom-made femoral stem. The medical image of the hip obtained according to the patient X-rays. The geometric parameters for femoral stem were established based on the canal flare index. The necessary constrains based on surgical experience were integrated into the CAD system. The rapid prototyped model was built as the reference for review. Through the application of CAM software, the interference-free toolpath and the cutter location for multi-axis NC machining are generated. In order to establish the interface between the design and the manufacture of femoral stem, the postprocessor for multi-axis machine tool is developed. The cutting simulations with solid model are performed to verify the generated toolpath. It is also verified through the trial-cut with model material on a five-axis machine tool.

On the basis of the ball-end milling feature during high-speed machining impeller, the relationship between cutting force and chips is analyzed in this paper. The model of ball-end milling cutter cutting force is founded through differential method. And the coefficients solution of cutting force model is expounded. Besides, the coefficients solution and the cutting force model simulation are implemented by the software Matlab.

In recent years, ultraprecision micromachining technology draws wide attention. In particular, multi-axis control ultraprecision machine tools are playing an important role in producing complicated microparts made of a variety of materials. In addition, CAM software is also an essential element to control these machine tools. The paper deals not only with the current state of multi-axis control ultraprecision machine tools but also with the manufacture of two workpieces consisting of complicated shapes by means of micromilling.

Having studied the synchronized multi-axis control servo system, some type automatic wire striping and terminal crimping system is developed in the paper. In order to realize the precise and efficient synchronized multi-axis control, the PVT (Position-Velocity-Time) algorithm is adopted. This algorithm allows user to specify the time interval of each axis’ motion segment, so the multi-axis working sequence can be easily established in a tight way which augments the system processing speed and guarantees the system stability. Besides, by specifying the position and speed value at the processing point, the positioning accuracy and speed requirement at the processing point can be reached. In the design of the system control software, the modularization design is employed. This modularization idea simplifies the complex software design and allows people use the software more easily. Finally, the experimental result shows the system has a good synchronization performance, and meets the requirements of high efficiency, stability and positioning accuracy in practical production.

In order to manufacture geometrically complex or hard material parts, a new kind of multi-axis electro-discharge machining (EDM) computer numerical control (CNC) system, which is based on RT-Linux platform, was presented. Dual-kernel structure of System is adopted: Linux and RT-Linux are used to realize Time-sharing tasks and Real-time tasks separately. The system is divided macroscopically into two parts: Real-time part and Time-sharing part, microcosmically into three modules: Real-time Control Module, Drive Module and CNC User Module. Through the communications among them, three modules construct the whole system. Rimed Turbine Blisk was experimentalized to validate the performance of the system. The process and the results implied that the system is Real-time, stable and reliable.

In order to improve machining quality and productivity of complex curved surfaces in high-speed wire electrical discharge machining (HS-WEDM), an additional numerical control (NC) worktable (rotation-swing-swing worktable) and its NC system were designed. The movement model of the four-axle linkage system was established and simulation was developed using the programming language Visual C++ and standard connection software OpenGL.

In order to achieve higher product quality for sculptured surface productions, an advanced strategy are proposed for machining planning, namely a tool-posture-control strategy. In the tool-posture-control strategy, machining chatter is reduced by controlling the machine rigidity along cutting feed direction. This proposed strategy, which improved product quality of sculptured surface when subjected to both the part geometry and the machine rigidity constrains, is described in this paper. A new machining-planning aid called local stiffness index is developed to help tool posture planning. This proposed strategy subjected to multi-constrains help a part programmer to choice the optimum tool posture. In order to illustrate the application of stiffness index map and the proposed strategy, the applications of the proposed strategy to real three-dimensional complex surface (e.g. a turbine blade) are presented in this paper.

Introduced systematically the forming principles and mathematical modeling of grinding/ milling spiral flutes with numeric control machines, overviewed the functions of multi-axis linkage and the determination technique of the number of the linkage axes, discussed the conversion technique of NC—STEP-NC code in programming with EXPRESS, presented advances of controlling systems with high performance. Much attention was paid to the explanation of the error modeling and the tool interference in the real machining with the error-compensation techniques. Trends were envisioned on key technique study of the forming principles for the spatial spiral flutes, function of multi-axes, tool interference in the real machining and simulation of the operation processing, as well as automatic generation of NC codes and the connection /compatibility of the codes with the mainline NC systems, in future.

A series of severe strain compression tests of a pipe line steel were conducted using the MAXStrain® system. The tests were run at different thermal mechanical conditions including controlled cooling rates. 1-2 micron ultrafine grain microstructure was achieved. The characteristics of the ultrafine grain structure and precipitates were examined using optical microscope, SEM, and TEM, and the relationship between the processing conditions and microstructure and precipitates were studied.

Lightweight structures are an important element in today’s production industry. For the multi-axis milling of these structures some aspects have to be considered to achieve a good surface quality and to prevent damaging the milling machine during the machining process. In this article methods to determine suitable feed rates for the milling process, to identify parts of the workpiece with too much heat build-up, and to avoid collisions between workpiece and machine parts are presented. For this purpose a milling simulation based on a multi-dexel field workpiece model has been developed, in which two types of feed rate adaptation have been integrated. Work on a built-in temperature development simulation and collision control is in progress.

The main difficulties in dealing with extremely high speed precision contouring control are system uncertainties and external disturbances, which exist in all CNC mechanisms and hard to be eliminated. Up to the present, numerous control strategies for multi-axial contouring control have been proposed. Some of them are only for specific contour conditions. This paper surveys several formulations in dealing with contouring control system, instead of the controller design. The distinguishing features of these control structures are also addressed.

This paper discusses the development of a novel processing route to produce ultra finegrain bulk alloy forgings; the microstructural response of these forgings to thermal exposure; and the comparison of mechanical properties to those from conventionally processed material. A Ni- 20Cr [wt%] alloy was processed by near-isothermal multi-axis forging to a grain size of approximately 1 μm. A heat-treatment study over the range 900 to 1200°C was conducted to determine the resultant grain size as a function of time and temperature. Tensile properties were measured at room temperature, 500°C, and 930°C. High-cycle fatigue properties were measured at room temperature. The room-temperature tensile strength was approximately 2.5 times greater than that of conventionally processed Ni-20Cr. Fatigue data showed that the room-temperature highcycle fatigue run-out stress was greater than 100% of the yield stress.