Materials Science Forum Vols. 800-801

Abstract: In this paper, we use the finite element simulation method to create a three-dimensional thermal mechanical coupled model that simulate the distribution of residual stress under condition of hard turning GCr15. And twice consecutive cutting simulation are required, then analysised the influence rule of two consecutive machining on surface residual stress distribution. The simulation results were compared with the experimental values, the results show that the simulated values of continuous cutting was very closed to the experimental values and the simulation results showed a certain reliability, the maximum residual tensile stress value increased significantly as the cutting speed increased.

Abstract: Residual stress ,with the branch of type, size and direction, is defined as the stress state which exists in a body after all the external loads are removed [1].According to the mutual influence scope size,residual stress can be divided into macroscopic residual stress and micro residual stress. Cutting residual stress is mainly caused by mechanical stress, thermal stress and phase transformation.

Abstract: High speed turn-milling has superiority on the productivity and the quality of work pieces, and is more suitable to machine micro-shaft parts and desirable miniature parts based on the turn-milling technology. In this papers adopting orthogonal experiment method cutting experiments of orthogonal turn-milling Aluminum alloy have been done. The relation between turn-milling regimes (cutter rotate speed, axial feed, feed per tooth etc.) and machined surface roughness has been ascertained. Finally, primary and secondary order of cutting regimes impacting surface roughness has more been confirmed through orthogonal experiments variance analysis, the rotate speed of cutter (cutting speed) influence greatly on surface roughness. Through 2-dimension surface topography diagram and 3-dimension surface topography of processed surface, it can be seen that high speed turn-milling processing technology can process micro miniature component of high surface quality, and features excellent development prospect and application value.

Abstract: The work-piece surface quality reflects the cutting performance of face-milling cutter. This paper presents the development of an algorithm to predict work-piece surface roughness in face milling operation. The prediction model is based on the face milling cutter fixed square inserts with flat edges. The static prediction model considers the effects of radial and axial run-out error of inserts, feed per tooth, tooth number, cutting edge length, nose radius, main lead angle, and axial depth of cut. The dynamic prediction model considers the effects of the Z-axial relative displacement between the work-piece and cutting teeth caused by forced vibration. By combining the prediction results of static and dynamic models, the surface roughness of the work-piece in face milling is predicted.

Abstract: The paper presents rigorous experimental validation results of the algorithm to predict work-piece surface roughness in face milling operation as developed in the Part 1. The experimental verification system consisting of various devices was established according to the given experimental conditions. Experimental parameters are set for steady face milling. Experimental data are collected through four experiments. These experimental data include the axial and radial run-out errors of each square insert with flat edge, the modal parameters of the face milling system, the Z-axial milling force and the measured surface contour of the milled work-piece. The trajectory of cutting teeth is calculated by the MATLAB software based on the static surface roughness model. Z-axial dynamic relative displacement between the tooth and the work-piece is obtained as the predicted dynamic surface roughness. By integrating the prediction results of static and dynamic models, the surface contour is predicted. Predicted and measured results are compared in the same figure and basically consistent. The work-piece surface roughness prediction model will be useful and valid in high-speed face milling.

Abstract: The powder preparation, material properties, the cutting characteristics and parameter selection for a nickel base superalloy FGH97 are summarized in this paper. It introduces the influence of various elements on the properties of the alloy, the ideal tool materials is coated cemented carbide tool and PCBN ceramic cutting tool. Generally we can choose the rake angle of 0°~10°, clearance angle of 6°~12°, cutting edge angle of 30°~60°, distortion angle of 0.5°~3°, tool cutting edge inclination angle of-10°~-20°. The optimal parameters for machining superalloy is axial cutting depth (range from 0.15~0.20mm), radial cutting depth (range from 10~20mm), the cutting speed (range from 40~60m/min), feed per tooth (range from 0.08~0.10mm/z).

Abstract: This study is focused on the optimization of the grinding process parameters for the grinding of the CVD diamond micro-milling tool. Two types of CVD diamond i.e. CDM and CDE are used for the study. Feed rate and the grinding velocity are used as the grinding parameters. The optimizations of the parameters are done by studying the two results i.e. grinding force and cutting edge radius. Highest grinding velocity and medium feed rate is found to have the best result for the grinding of the CVD diamond. Keywords: CVD diamond, Grinding, Micro-tool

Abstract: In this paper, titanium as the research object, which is usually used as the aerospace engine blisk manufacturing materials, as a typical difficult-to-machine materials, on the basis of its machinability is analysis, research process bisk processing of the main types of flank milling, flank milling fundamental experiments of titanium was carried out, the cutting force of the processing is collected and analyzed in order to optimize the process parameters; Studying ball end mill for the stress analysis and modal analysis in order to obtain the stress, strain and distribution of vibrations in the flank milling titanium, which can provide a reference for future flank milling process parameters titanium blisk, and provide theoretical basis for efficient, stable and safe cutting and optimization tool design.

Abstract: Due to the rapid development of aerospace industry, the amount of cutting data is increasing. Establishing cutting database for aerospace industry is necessary. Therefore, this article designs the typical aerospace material database system. According to project requirements analysis and the conceptual design, nine function blocks is set. They are data management, experiment management, optimization management, cutting tool design, cutting tool simulation, knowledge base, aerospace solutions, systems management, and help. And the article describes content and processes of every function block.

Abstract: This paper proposes a method to choose machine resources in order to realize the on-demand use of machine resources in cloud manufacturing environment. A convergence mode of the machine resources is described and the selection process is given. A multi-level matching process of machine tools is proposed. Different matching methods are designed for different parameter types of machining tasks and machine resources, and then machine resources are screened according to the requirements of machining tasks to form the machine resources candidate sets. Then a multi-objective optimal selection model of machine resources is constructed, regarding minimization of costs and time and maximization of service quality and reputation as the target, which is solved by using genetic algorithms. Finally, the algorithm is analyzed and validated with an example, and a kind of solution thinking and method is provided to select machine tools in manufacturing cloud environment.