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1

Multi-criteria optimization of the turning parameters of Ti-6Al-4V titanium alloy using the Response Surface Methodology

Kluz Rafał, Habrat Witold, Bucior Magdalena, Krupa Krzysztof, Sęp Jarosław

Eksploatacja i Niezawodność

|

2022

|

Vol. 24, no. 4

668--676

EN

The paper depicts an application of Response Surface Methodology (RSM) for predicting selected parameters in turning of Ti-6Al-4V titanium alloy using polycrystalline diamond tool. Response surface plots that are generated by the model helps in determining the optimum combination of input factors (cutting speed vc and feed rate f) for best possible surface roughness (Sa), cutting force (Fc)and temperature (T) for dry and cooling turning. The methodology of multi-criteria optimization was used to establish the interaction between input parameters and given responses.

2

Modeling of Vibration Behaviors of Turning Machining with the Constant Surface Speed Effect

Royandi Muhamad Aditya, Effendi Iman Apriana, Ibrahim Bustami, Hung Jui Pin

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 3

134--145

EN

Turning machining is a complex process in which many variables can influence the desired results. Among those variables, cutting tool vibration and cutting force greatly affect the precision of the workpiece and the tool life. While the tool vibration and cutting force in feeding are primarily determined by cutting speed, feed rate, and depth of cut as well as the dynamic characteristics of the machining system. This paper presents an analytical modeling approach to investigate the effects of machining conditions based on the governing equation of the machining system. The machining behaviors under different conditions were simulated by Simulink block diagram. Basically, the cutting speed is considered the parameter dominating the vibration behavior and hence is served as the primary input for the simulation. The effectiveness of constant surface speed (CSS mode) or function G96 in the turning process was further examined through comparisons of the variations of vibration and cutting force generated in feeding with different conditions.

3

Multiobjective optimization of multipass turning machining process using the Genetic Algorithms solution

Amiolemhen Patrick Ejebheare, Eseigbe Joshua Ahurome

Journal of Mechanical and Energy Engineering

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2019

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Vol. 3, No 2

97--108

EN

The study involves the development of multi-objective optimization model for turning machining process. This model was developed using a GA - based weighted-sum of minimum production cost and time criteria of multipass turning machining process subject to relevant technological/practical constraints. The results of the single-objective machining process optimization models for the multipass turning machining process when compared with those of multi-objective machining process model yielded the minimum production cost and minimum production time as $5.775 and 8.320 min respectively (and the corresponding production time and production cost as 12.996 min and $6.992, respectively), while those of the multi-objective machining process optimization model were $5.841and 9.097 min. Thus, the multi-objective machining process optimization model performed better than each of the single-objective model for the two criteria of minimum production cost and minimum production time respectively. The results also show that minimum production time model performs better than the minimum production cost model. For the example considered, the multi-objective model gave a lower production time of 30.0% than the corresponding production time obtained from the minimum production cost model, while it gave a lower production cost of 16.46% than the corresponding cost obtained by the minimum production time model.

4

System Identification and Model Predictive Control of the Chatter Phenomenon in Turning Process

Karimipour Atiyeh, Emami Mohsen

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 3

217--228

EN

Chatter is a series of unwanted and extreme vibrations which frequently happens during different machining processes and impose variety of adverse effects on the machine-tool and surface finish. Chatter has two main types namely forced-chatter and self-existed chatter. The forced-chatter has an external cause; however, self-exited chatter has no external stimuli, rather it is created due to the phase difference between the previous and current waves on the surface of the workpiece. Due to the self-generative nature of this type of chatter, its recognition and prevention is much more difficult. For preventing self-exited chatter its model should be available first. The chatter is usually simulated as a one degree of freedom mass-spring-damper model with unknown parameters that they should be determined somehow. In this paper, the parameters of the tool equation of motion i.e. mass, damping, and stiffness coefficients of the system are predicted through a wavelet-based method online, and then based on the achieved parameters, the system is controlled via Model Predictive Control (MPC) approach. For the validation, the algorithm is applied to 25 different experimental tests in which the acceleration of the tool and cutting force are measured via an accelerometer and a dynamometer. By investigation of the SLDs generated by the predicted parameters, the presented system identification method is validated. Also, it is shown that the chatter vibration is completely restrained by means of MPC. For investigation of the MPC performance, MPC algorithm is compared with PID controller and simulations has indicated a much stronger performance of MPC rather than PID controller in terms of vibration attenuation and control effort.

5

Podstawy technologiczne wielokryterialnej optymalizacji procesów toczenia złożonych powierzchni narzędziami punktowymi

Zawora J.

Prace Naukowe Politechniki Warszawskiej. Mechanika

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2013

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z. 255

3--176

PL

Praca poświęcona jest problematyce dotyczącej procesu toczenia złożonych powierzchni narzędziami punktowymi. Proces może być realizowany na tokarkach i automatach tokarskich CNC oraz tokarkach kopiarkach. Celem pracy jest rozwiązanie zagadnień niezbędnych do utworzenia technologicznych podstaw optymalizacji wielokryterialnej procesu toczenia złożonych zarysów narzędziami punktowymi. Utworzone podstawy wielokryterialnej optymalizacji mogą być wykorzystane do budowy postprocesorów technologicznych w modułach technologicznych systemów CAD/CAM. Proces toczenia kształtowego przebiega w bardzo złożonych warunkach fizycznych ze względu na zmienność parametrów obróbki, takich jak: prędkość skrawania, posuw, głębokość skrawania oraz kąty zarysu przedmiotu obrabianego. W czasie zmiennych warunków obróbki występują zmienne pola temperatur, naprężeń i odkształceń sprężysto-plastycznych, występuje zmiana wartości i rozkładu współczynnika tarcia, zmiana kształtu przekroju warstwy skrawanej, kąta ścinania, roboczych kątów przystawienia itp. Zmiany kątów zarysu są przyczyną zmiany kierunku i wartości wektora prędkości posuwu, co powoduje powstawanie składowych sił dynamicznych o znacznej wartości. Zmienność warunków pracy powoduje zmienne obciążenia, drgania i wpływa na zużycie ostrza. Przeprowadzono analizę złożonego przebiegu zjawisk odnośnie obliczania trwałości ostrza i wartości składowych sił skrawania w zmiennych warunkach obróbki oraz warunków tworzenia teoretycznej chropowatości powierzchni obrobionej. Opracowano zasady przeprowadzania badań procesu z zastosowaniem techniki planowania eksperymentu oraz opracowano model matematyczny procesu i dokonano jego oceny statystycznej. Do wyznaczenia charakterystyki zużycia ostrza w funkcji bezwymiarowej wielkości t/T oraz w/W opracowano algorytm aproksymacji z zadanym warunkiem wymuszenia przejścia funkcji przez punkt początku układu współrzędnych. Opracowano nową metodę badania dokładności tych charakterystyk umożliwiającej obliczanie trwałości ostrza w zmiennych warunkach obróbki. Opracowano nowy doświadczalny model matematyczny sił dynamicznych i czasu narastania głównej siły dynamicznej w strefach przejściowych. Podano zasady obliczania trwałości ostrza i innych wielkości wyjściowych w procesie toczenia złożonych powierzchni. Zaproponowano nową metodę obliczania trwałości ostrza w zmiennych warunkach obróbki z uwzględnieniem wpływu sił dynamicznych. Wykonano programy numeryczne optymalizacji jednokryterialnej i wielokryterialnej do optymalizacji parametrów skrawania w zmiennych warunkach obróbki procesu toczenia złożonych zarysów i wskazano na dalsze kierunki rozwoju prac w rozważanym procesie.

EN

Contour turning with a point-tip tool is very a complex process due to variation of machining parameters: cutting speed, feed of the cut, depth of the cut and contour angle of the cut surface. Variable fields of temperature, stress and elastic-plastic deformation develop during the machining, friction coefficient varies, the shape of the cut section changes along with shear angle, instant tool cutting edge angle and so on. Changes in contour angle values imply changes of cutting feed direction and its value, which results in additional dynamic force components of considerable level. Due to varying conditions of operation, cutting force components fluctuate, which is connected with varying load and the resultant tool wear. The present CAD/CAM systems do not offer cutting parameter optimization in manufacturing modules. Elaboration of basic multi-criterion optimization of contour turning with a point-tip tool which could be applied in the NC post-processing development is the major goal of this work. Making use of experience gained when investigating the contour turning process and the works concerning the contour turning process carried out in varying conditions, the author elaborated an experimental mathematical model of the contour turning process. A new method for estimating the accuracy of the tool wear relationship on dimensionless t/T or w/W variable has been elaborated and a new model of dynamic forces has been proposed. The tool wear relationship is then not affected by cutting parameters. A new method of tool life calculation in varying machining conditions has been elaborated for the parts of complex shapes. The associated software has been developed using the FORTRAN language for the case of single criterion and limited weight-based multi-criterion case. New principles of tool life calculations have been elaborated, accounting for dynamic force components occurring in the areas where the shape changes instantly. This has been accomplished by elaboration of the tool wear relationship with the dimensionless operation parameter w/W. The author made an analysis of complex phenomena taking place in the contour turning process and the resultant surface roughness. The obtained results may be applied in contour cutting on tracer lathes or numerically controlled lathes.

6

Modelowanie i symulacja procesu toczenia stali niestopowej

Zatorski Z.

Biuletyn Wojskowej Akademii Technicznej

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2013

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Vol. 62, nr 2

233-246

PL

W pracy pokazano możliwości wykorzystania technik komputerowych w zakresie techniki skrawania, zwłaszcza analitycznego i numerycznego modelowania procesu skrawania stali niestopowej i jego weryfikacji doświadczalnej. Komputerowe wspomaganie wytwarzania realizowano w programie EdgeCAM. Dobór parametrów i warunków skrawania przeprowadzono w programie CoroGuide dla narzędzi firmy AB Sandvik Coromant. Eksperymentalną walidację procesu skrawania prototypu z tworzyw sztucznych oraz wyrobów ze stali przeprowadzono na tokarce CNC.

EN

The presented work shows the use of computer technique in a range of machining, especially analytical and numerical modelling of machining process of unalloyed steel as well as its experimental verification. Computer aided manufacturing was realized with EdgeCAM code. Selection of parameters and conditions of turning has relied on AB Sandvik Coromant tools according to CoroGuide code. Experimental validation of machining of plastic prototype and steel workpiece has been made using CNC machine.

7

PC controlled turning tool

Mikołajczyk T., Kamieniecki Ł.

Journal of Polish CIMAC

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2012

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Vol. 7, no 3

199-204

EN

Design of PC controlled turning tool is presented in paper. Tool placed in the guides was driving using the stepper motor and a screw cooperating with the nut joined with the tool. To control of the tool was used PC with the step motor interface connected to the LPT port. Mounted to the holder tool allows machining shape surface using the universal lathe.

8

Influence of Friction Coefficient in Tool : Object Contact Zone on State of Surface Layer After Turning Process

Forysiewicz M., Kukiełka L.

Machine Dynamics Research

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2010

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Vol. 34, No. 2

21-27

EN

The work concerns on the analysis of the influence of selected parameters of rolling process on state of surface layer. The numerical application in APDL language, in ANSYS/LS-Dyna system, for analysis of physical phenomena (strains) which occur in surface layer of material was developed. Physical phenomena, on a typical incremental step, were described in an updated Lagrange'a description, which shows the lowest sensitivity on large deformations. Carried out simulations for machining of various materials, which are characterized by a different plastic strain, allows to determine the factors influence on the shape of chip and wear of a turning tool which determine quality (surface roughness of the product). During the rolling process the influence of friction coefficient on the state of surface layer of processing material was investigated. The examples of numerical simulations results for selected time steps were presented.

9

Solid works w funkcji wpływu parametru modelowania na chropowatość podczas procesu toczenia

Kuzinovski M., Smileski T., Tomov M.

Górnictwo Odkrywkowe

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2010

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R. 51, nr 3

154-159

PL

W artykule przedstawiono otrzymane modele matematyczne do określenia parametrów Rt, Ra, Rv, Rp, RSm i Rmr(c) profilu chropowatości elementów obrabianych przez obrót. Profil chropowatości uzyskuje się w wyniku kinematycznej geometrii kopiowania narzędzia tnącego na nowo powstałą powierzchnię, biorąc pod uwagę wpływ zmiany kątów promienia r oraz posuwu f. Weryfikacja osiągniętych modeli matematycznych wykonano biorąc pod uwagę parametr modelowania na profilu chropowatości przy użyciu oprogramowania SolidWorks.

EN

The study presents achieved mathematical models for determination ofparameters Rt, Ra, Rv, Rp, RSm and Rmr(c) on roughness profile machined by turning. The roughness profile is achieved as a result of cinematic-geometry copying of the cutting tool on the new formed surface, considering the influence from the change of angles. Verification of the achieved mathematical models is made with parameter modeling on the roughness profile by use of software program SolidWorks.

10

Drgania okresowe, prawie okresowe i chaotyczne w procesach toczenia

Łuczko J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2008

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z. 74 [258]

221-232

EN

The paper is concerned with qualitative analysis of a non-linear model describing the vibrations in cutting processes. The model of the regenerative turning process is described by two delay differential equations. The influence of selected parameters such as the rotational velocity and the frequency of the kinematic excitations as well as the cutting speed and the cutting resistance on the character and level of vibrations is studied. The possibility of the excitation of quasi-periodic or chaotic oscillations for some values of the parameters has been shown. Zones of the sub-harmonic, quasi-periodic and chaotic vibrations were estimated by the methods of numerical integration. Bifurcation diagrams have been used to explain the phenomenon of vibration synchronization. Different types of vibration are illustrated by plots of time histories, phase and stroboscopic portraits.

11

Problematyka przygotowania powierzchni w procesie toczenia w aspekcie jakości technologicznej wyrobu nagniatanego

Kułakowska A., Kukiełka L.

Pomiary Automatyka Kontrola

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2008

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R. 54, nr 7

421-424

PL

Praca dotyczy problematyki przygotowania powierzchni w procesie toczenia w aspekcie jakości technologicznej wyrobu nagniatanego. Badania przeprowadzono w celu ustalenia zależności pomiędzy wybranymi parametrami chropowatości powierzchni wyrobu po nagniataniu a warunkami obróbki toczeniem. Określono obiekt badań i funkcję jakościową. Ustalono zakres zmienności czynników badanych. Wykonano proces toczenia i nagniatania. Wyniki pomiarów opracowano statystycznie. W rezultacie przeprowadzonej analizy otrzymano funkcję regresji. Sporządzono przykładowy wykres.

EN

In the paper problems of surface preparation in turning process in aspect of technological quality of burnished product is shown. The aim of the researches was to determine the dependence between the chosen roughness parameters of the burnished product and conditions of turning process. The object of the researches and the qualitative function were defined. The range of the variable factors was determined. The turning and burnishing process was performed. The results were statistical elaborated. As the result the function of regression was determined and exemplary graph was created.

12

Turning-form electrode in ultrasonic-aided electrochemical finishing

Pa P. S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 21, nr 2

77-80

EN

Purpose: The ultrasonic-aided electrochemical finishing following traditional turning by a turning-form electrode for several die materials is demonstrated. Design/methodology/approach: A guide line for the design process is followed a scientific method including the design requirement, design development, detail design, and experimental analysis is adopted in the current study. The proposed design of turning-form electrode combined with the ultrasonic-aided electrochemical finishing is presented. Findings: Smaller end radius and smaller declination angle are associated with higher current density and provides larger discharge space and better polishing effect. The plate-shape electrode with small end radius and decreasing the surface area of top-view performs the best. The ultrasonic assistance can avoid the difficulty of dreg discharge in the electrochemical finishing, thus increasing the finishing effect. Research limitations/implications: The potential for electrode design and using ultrasonic energy transmitted to the electrolyte to assist discharging dregs out of electrode gap during the electrochemical finishing is yet to be explored. Practical implications: This process can be used for various turning operations including end turning, form turning, and flute and thread cutting. Through simple equipment attachement, the electrochemical finishing can follow the cutting on the same machine and chuck. Originality/value: It is great contribution that the ultrasonic-aided electrochemical finishing after turning process just needs quite short time than manual or machine finishing to make the surface of workpiece smooth and bright. An effective and low-cost finishing method after turning process is presented.

13

Skrawanie toczeniem elementów o przekroju niekołowym

Rusinek R., Warmiński J.

Eksploatacja i Niezawodność

|

2004

|

nr 4

30-33

PL

W pracy przedstawiono wyniki badań eksperymentalnych toczenia skrawaniem elementu metalowego o prostokątnym przekroju poprzecznym. Zaproponowano matematyczny opis takiego układu w postaci równań różniczkowych zawierających wzbudzenie parametryczne. W badaniach doświadczalnych wykazano związek pomiędzy częstością i amplitudą drgań a prędkością wrzeciona.

EN

Analysis of a turning process of a workpiece with a rectangular cross section is presented in the paper. Results of experimental investigations are shown. A mathematical model of parametric vibrations caused by stiffness changing is also proposed. A connection between vibrations frequency and rotational speed of a chuck is proved on the basis of experiment.

14

Zastosowanie sieci neuronowych do modelowania odksztalcen przedmiotu obrabianego podczas toczenia

Jóźwik J., Lipski J.

Eksploatacja i Niezawodność

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2002

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nr 4(16)

30-39

PL

W artykule wskazano na szerokie możliwości modelowania procesów skrawania za pomocą strategii samouczenia. Zaprezentowano model predykcji sumarycznych odkształceń przedmiotu obrabianego za pomocą sztucznych sieci neuronowych. Badania i analizy przeprowadzono na przykładzie toczenia ortogonalnego tulei cienkościennej, poddanej działaniu ciepła i sił w procesie skrawania.

EN

In this paper has been to shown wide possibility modeling of cutting process by self-teaching strategy. Hear have been presented neural network model of workpiece summary deformations. Research and analyzes have been shown based on example orthogonal turning of thin-walled sleeve to expose it on action of heat and cutting forces.