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The Development of Decision-Making Maps for the High-Speed Machining (HSM) of Rhyodacite (Carijó Basalt) in Milling-Based Processing Applications  [PDF]
Hélio Dorneles Etchepare, Wilson Kindlein Júnior
Modern Mechanical Engineering (MME) , 2013, DOI: 10.4236/mme.2013.34025
Abstract:

The demand for innovative products that overcome competitive pricing and conquer market shares can be met by interdisciplinary approaches that bridge product design, engineering and technology. Ornamental and covering stones stand out among the materials in need of innovation and are commonly used in architecture and construction as coverings in urban elements, funerary art, and art and decor. In spite of the many applications of ornamental stones, products with low added value are typically observed. Although Brazil displays significant geological potential for ornamental stones, its actual market participation is as a supplier of un- or semi-processed stones. Even with the market’s visible expansion and Brazil’s increased representation in the market, the technological advances used in the final processing of stones are restricted to improve the tools used for cutting, especially the durability of diamond-coated tools, and for polishing, which, in the short-term, meets the demands for marketing, producing and distributing semi-finished products. Accordingly, a little exploited aspect of ornamental stones appears, especially for “carijó basalt” (rhyodacite), that is, the inclusion of new processing and value-adding technologies or the inclusion of non-conventional processes in the sector. The goals of this work are to study and develop HSM (high speed machining) CNC (computer numerically controlled) milling processes that are applicable to rhyodacite, specifically to determine the milling parameters that give the best results for machining time with respect to tool wear and material abrasion and to replicate the results obtained in the samples. The results show that the raw material used in the present study, because it is natural, presents significant variations in composition and hardness, which prevent specific milling parameters from being determined. However, using a post-processor specifically developed for this study, it was possible to draft a decision-making map

Circular tests for HSM machine tools: Bore machining application  [PDF]
Laurent Tapie,Kwamiwi Mawussi,Bernard Anselmetti
Computer Science , 2009, DOI: 10.1016/j.ijmachtools.2006.06.021
Abstract: Today's High-Speed Machining (HSM) machine tool combines productivity and part quality. The difficulty inherent in HSM operations lies in understanding the impact of machine tool behaviour on machining time and part quality. Analysis of some of the relevant ISO standards (230-1998, 10791-1998) and a complementary protocol for better understanding HSM technology are presented in the first part of this paper. These ISO standards are devoted to the procedures implemented in order to study the behavior of machine tool. As these procedures do not integrate HSM technology, the need for HSM machine tool tests becomes critical to improving the trade-off between machining time and part quality. A new protocol for analysing the HSM technology impact during circular interpolation is presented in the second part of the paper. This protocol which allows evaluating kinematic machine tool behaviour during circular interpolation was designed from tests without machining. These tests are discussed and their results analysed in the paper. During the circular interpolation, axis capacities (such as acceleration or Jerk) related to certain setting parameters of the numerical control unit have a significant impact on the value of the feed rate. Consequently, a kinematic model for a circular-interpolated trajectory was developed on the basis of these parameters. Moreover, the link between part accuracy and kinematic machine tool behaviour was established. The kinematic model was ultimately validated on a bore machining simulation.
Simulation and Optimization of Turning-Milling Complex Machining
Anjiang Cai,Mingwei Ding,Shihong Guo,Hong Lin
Research Journal of Applied Sciences, Engineering and Technology , 2013,
Abstract: In this study, the turning-milling complex processing simulation platform is established based on the simulation and optimization platform of VERICUT NC machining, with WFL M65 turning-milling complex machining center as the research object; taking barrel body parts as an example, the simulation machining and related process issues checking in machining process is made and the analysis and optimization of effect factors is made for processing efficiency. The application indicates that: the research results effectively realize the simulation of the turning-milling complex machining process and the correctness verification and process optimization of the NC machining program, improve the processing efficiency and the processing quality, well improve the application level of enterprise turning-milling complex machining center, promote the development of the turning-milling complex machining technology.
Determination of machining parameters in HSM through TSK-FLC  [PDF]
A.K. Nandi
Journal of Achievements in Materials and Manufacturing Engineering , 2007,
Abstract: Purpose: The optimal setting of machining parameters that may be realized via a suitable model/controller is an important concern to fulfill the overall objectives in machining.Design/methodology/approach: The present paper proposes an approach for determination of optimal setting of machining parameters in high speed climb milling operation through an TSK-type fuzzy logic controller (TSK-FLC). A novel approach is proposed here which combines the techniques of linear regression (LR) and genetic algorithm (GA) to utilize the advantages of each other, in order to develop an efficient FLC for high-speed milling.Findings: Modeling of manufacturing process enables generating of manufacturing data and knowledge representation in machining process. Comparisons of results with real experimental data as well as those obtained by other common methods of modeling show the effectiveness of the FLC.Research limitations/implications: The design approach of fuzzy logic controller uses experimental data for learning. The shape of fuzzy subsets as well as the structure(s) of rule consequent functions are the important concern for optimal knowledgebase (KB) of a FLC. Use of the advantages of both LR and GA makes it possible to achieve optimal KB of FLC.Practical implications: Use of developed FLC results in improved productivity and efficiency of machining process via the setting of optimal values of cutting parameters and the possiblilty to develop automatic manufacturing system by online determination of machining parameters.Originality/value: The paper describes a method for desiging a FLC for manufacturing process by a combination of LR and GA, which leads to eliminate a long regression function as required in standard linear regression method.
THE INFLUENCE OF SOLID LUBRICANT IN MACHINING PARAMETER OF MILLING OPERATION
Z.A. Zailani,,R. Hamidon,,M.S Hussin,,M.F.M.A Hamzas
International Journal of Engineering Science and Technology , 2011,
Abstract: Milling is a widely material removal process for different materials. It is characterized by high material removal rate. Machining leads to high friction between tool and workpiece, and can result in high temperatures, impairing the dimensional accuracy and the surface quality of the products. Application of conventional cutting fluid may not effectively control the heat generation in milling. Besides, cutting fluids are major source of pollution. Solid lubricant assisted machining is an environmental clean technology for desirable control of cutting temperature. Hence, this project investigates the role of solid lubricant assisted machining with graphite powder extra pure on surface quality and tool wear while machining mild steel. There are four conditions of lubricants will be analyzed for this experiment. The conditions are fully ordinary coolant, and the mixture between ordinary coolant with 50 grams, 100 grams and 150 grams of graphite powder extra pure. The performance of solid lubricant assisted machining will be analyzed in measuring the reduction in tool wear and surface roughness and compare with wetmachining.
OPTIMIZING THE REST MACHINING DURING HSC MILLING OF PARTS WITH COMPLEX GEOMETRY
Rezo Aliyev
International Journal of Advances in Engineering and Technology , 2012,
Abstract: The process of HSC milling of complex geometry is carried out in several stages that include the rest machining, which is typical for manufacturing of parts with complex geometry. Since the rest machining is a more extensive stage than previously imagined, selection of favorable milling strategy in the rest machining stage requires a closer view. This paper presents the solution to the generation of milling strategies for rest machining by using commercial CAM systems, which offer a broad possibility for the organization of time-optimal machining sequence to assure the demanded surface quality. By application of these strategies, the standard tool paths are generated based on geometric computations only, not considering allowance dividing between the ball end milling tools, which are necessary for re-machining the residual materials areas at the workpiece with many cavities. In this work used algorithm makes it possible to select the optimal tool combination for rest machining with respect to surface quality.
Investigating Effect of Machining Parameters of CNC Milling on Surface Finish by Taguchi Method
Amit Joshi,Pradeep Kothiyal
International Journal on Theoretical and Applied Research in Mechanical Engineering , 2013,
Abstract: CNC End milling is a unique adaption of the conventional milling process which uses an end mill tool for the machining process. CNC Vertical End Milling Machining is a widely accepted material removal process used to manufacture components with complicated shapes and profiles. During the End milling process, the material is removed by the end mill cutter. The effects of various parameters of end milling process like spindle speed, depth of cut, feed rate have been investigated to reveal their Impact on surface finish using Taguchi Methodology. Experimental plan is performed by a Standard Orthogonal Array. The results of analysis of variance (ANOVA) indicate that the feed Rate is most influencing factor for modelling surface finish. The graph of S-N Ratio indicates the optimal setting of the machining parameter which gives the optimum value of surface finish. The optimal set of process parameters has also been predicted to maximize the surface finish.
Investigating Effect of Machining Parameters of CNC Milling on Surface Finish by Taguchi Method  [PDF]
Amit Joshi,Pradeep Kothiyal
International Journal on Theoretical and Applied Research in Mechanical Engineering , 2012,
Abstract: CNC End milling is a unique adaption of the conventional milling process which uses an end mill tool for the machining process. CNC Vertical End Milling Machining is a widely accepted material removal process used to manufacture components with complicated shapes and profiles. During the End milling process, the material is removed by the end mill cutter. The effects of various parameters of end milling process like spindle speed, depth of cut, feed rate have been investigated to reveal their Impact on surface finish using Taguchi Methodology. Experimental plan is performed by a Standard Orthogonal Array. The results of analysis of variance (ANOVA) indicate that the feed Rate is most influencing factor for modeling surface finish. The graph of S-N Ratio indicates the optimal setting of the machining parameter which gives the optimum value of surface finish. The optimal set of process parameters has also been predicted to maximize the surface finish.
An Investigation into the Use of Industrial Robots for Machining Soft and Low Density Materials with HSM Technique
Coelho, Reginaldo T.;Rodella, Hugo H.T.;Martins, Vinícius F.;Barba J., Rossana;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2011, DOI: 10.1590/S1678-58782011000300010
Abstract: the needs to comply with an increasingly competitive international market lead industries to some innovative solutions, such as the use of robotic arms as machine tools. although these solutions present some well known drawbacks, there are some advantages and niches of application where success is possible. the present work investigates the use of such pieces of equipment to machine aluminum alloys aa2024 applying high speed machining (hsm) technique, assessing surface finishing as a function of different orientation angles between end mill and machined surface. it also tests the best condition to machine foam for prototyping applications. results indicate that the directions close to the normal are the best compromises because of dynamic stability of the robot arm structure and roughness as low as 4 μm ra are possible to be achieved in aluminum alloys. a complex shape such as a semi sphere can be easily machined in foam for rapid and accurate prototype machining. surface finishing can be very smooth and well suitable for industrial applications in such materials.
Effect of Tool Cutter Immersion on Al-Si Bi-Metallic Materials in High-Speed-Milling  [PDF]
J.H. Soko?owski,D. Szablewski,W. Kasprzak,E.G. Ng
Journal of Achievements in Materials and Manufacturing Engineering , 2006,
Abstract: Purpose: Aluminum-Silicon (Al-Si) alloys are commonly used in the automotive industry. At high Si levels they offer good wear resistance. Abrasive wear however, has been identified as the main insert cutter damage mechanism during High-Speed-Milling (HSM). This study investigates the effect of the tool cutter immersion on Al-Si bi-metallic materials in HSM operation.Design/methodology/approach: This study considers the effects of the tool cutter immersion on the resultant cutting forces, associated machined surface roughness, and machined subsurface microstructural damage caused by the tool cutter during the Minimum Quantity Lubricant – High Speed Milling (MQL-HSM) operation of Al-Si bi-metallic materials with varying amounts and morphologies of the silicon phase.Findings: Experimental results indicate that a combination of gray cast iron with the W319 microstructure yields the greatest resistance to the tool cutter rake face during the face milling operation for all investigated tool cutter radial immersions. Machined surface roughness measurements reveal that surface roughness is a function of both the silicon content and morphology, as well as the percentage of tool cutter immersion. Matrix hardness measurements indicate that machining at all immersions has the same effect on compressing the matrix structure.Research limitations/implications: This study considers the effects of the radial tooling immersion and material selection while the speed, feed, and axial depth-of-cut are kept constant. Future work should address variability in the machining parameters in an attempt to maximize tool life, while optimizing the machined surface quality.Practical implications: Material selection affects the machining conditions in HSM of Al-Si bi-metallic materials. As a result careful consideration should be given when tailoring the machining conditions to the cast microstructures.Originality/value: North American automakers rely heavily on Al-Si precision sand cast components. As a result bi-metallic machining has to be often addressed during the face milling of engine blocks and cylinder heads. The research conducted here broadens the understanding of the impact of radial immersion on the machining behavior of Al-Si bi-metallic materials.
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