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Devotta, A. M., Sivaprasad, P. V., Beno, T. & Eynian, M. (2020). Predicting Continuous Chip to Segmented Chip Transition in Orthogonal Cutting of C45E Steel through Damage Modeling. Metals, 10(4), Article ID 519.
Open this publication in new window or tab >>Predicting Continuous Chip to Segmented Chip Transition in Orthogonal Cutting of C45E Steel through Damage Modeling
2020 (English)In: Metals, ISSN 2075-4701, Vol. 10, no 4, article id 519Article in journal (Refereed) Published
Abstract [en]

Machining process modeling has been an active endeavor for more than a century and it has been reported to be able to predict industrially relevant process outcomes. Recent advances in the fundamental understanding of material behavior and material modeling aids in improving the sustainability of industrial machining process. In this work, the flow stress behavior of C45E steel is modeled by modifying the well-known Johnson-Cook model that incorporates the dynamic strain aging (DSA) influence. The modification is based on the Voyiadjis-Abed-Rusinek (VAR) material model approach. The modified JC model provides the possibility for the first time to include DSA influence in chip formation simulations. The transition from continuous to segmented chip for varying rake angle and feed at constant cutting velocity is predicted while using the ductile damage modeling approach with two different fracture initiation strain models (Autenrieth fracture initiation strain model and Karp fracture initiation strain model). The result shows that chip segmentation intensity and frequency is sensitive to fracture initiation strain models. The Autenrieth fracture initiation strain model can predict the transition from continuous to segmented chip qualitatively. The study shows the transition from continuous chip to segmented chip for varying feed rates and rake angles for the first time. The study highlights the need for material testing at strain, strain rate, and temperature prevalent in the machining process for the development of flow stress and fracture models.

Place, publisher, year, edition, pages
MDPI, 2020
Keywords
chip segmentation, damage modeling, dynamic strain aging
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22346 (URN)10.3390/met10040519 (DOI)000531826500098 ()2-s2.0-85083847260 (Scopus ID)
Funder
Knowledge Foundation, 20110263, 20140130
Note

CC BY 4.0

Correspondence: ashwin.devotta@sandvik.com; Tel.: +46-706-163-722

This research was funded by Sandvik Coromant AB and the Knowledge Foundation through the Industrial Research School SiCoMaP, Dnr 20110263, 20140130.

Available from: 2023-03-31 Created: 2023-03-31 Last updated: 2023-03-31Bibliographically approved
Devotta, A. M., Sivaprasad, P. V., Beno, T., Eynian, M., Hurtig, K., Magnevall, M. & Lundblad, M. (2019). A modified Johnson-Cook model for ferritic-pearlitic steel in dynamic strain aging regime. Metals, 9(5), Article ID 528.
Open this publication in new window or tab >>A modified Johnson-Cook model for ferritic-pearlitic steel in dynamic strain aging regime
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2019 (English)In: Metals, ISSN 2075-4701, Vol. 9, no 5, article id 528Article in journal (Refereed) Published
Abstract [en]

In this study, the flow stress behavior of ferritic-pearlitic steel (C45E steel) is investigated through isothermal compression testing at different strain rates (1 s-1, 5 s-1, and 60 s-1) and temperatures ranging from 200 to 700 °C. The stress-strain curves obtained from experimental testing were post-processed to obtain true stress-true plastic strain curves. To fit the experimental data to well-known material models, Johnson-Cook (J-C) model was investigated and found to have a poor fit. Analysis of the flow stress as a function of temperature and strain rate showed that among other deformation mechanisms dynamic strain aging mechanism was active between the temperature range 200 and 400 °C for varying strain rates and J-C model is unable to capture this phenomenon. This lead to the need to modify the J-C model for the material under investigation. Therefore, the original J-C model parameters A, B and n are modified using the polynomial equation to capture its dependence on temperature and strain rate. The results show the ability of the modified J-C model to describe the flow behavior satisfactorily while dynamic strain aging was operative. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.

Place, publisher, year, edition, pages
MDPI, 2019
Keywords
flow stress, modified Johnson-Cook model, dynamic strain aging
National Category
Manufacturing, Surface and Joining Technology Metallurgy and Metallic Materials
Identifiers
urn:nbn:se:his:diva-22351 (URN)10.3390/met9050528 (DOI)000478818700046 ()2-s2.0-85066741813 (Scopus ID)
Funder
Swedish Research Council, 20110263, 20140130
Note

CC BY 4.0

Correspondence: ashwin.devotta@sandvik.com; Tel.: +46-706-163-722

This research was funded by Sandvik Coromant AB and the Knowledge Foundation through the Industrial Research School SiCoMaP, Dnr 20110263, 20140130.

Available from: 2019-06-20 Created: 2023-03-31Bibliographically approved
Agic, A., Eynian, M., Ståhl, J.-E. & Beno, T. (2019). Dynamic effects on cutting forces with highly positive versus highly negative cutting edge geometries. International Journal on Interactive Design and Manufacturing, 13(2), 557-565
Open this publication in new window or tab >>Dynamic effects on cutting forces with highly positive versus highly negative cutting edge geometries
2019 (English)In: International Journal on Interactive Design and Manufacturing, ISSN 1955-2513, E-ISSN 1955-2505, Vol. 13, no 2, p. 557-565Article in journal (Refereed) Published
Abstract [en]

Understanding the influence of the cutting edge geometry on the development of cutting forces during the milling process is of high importance in order to predict the mechanical loads on the cutting edge as well as the dynamic behavior on the milling tool. The work conducted in this study involves the force development over the entire engagement of a flute in milling, from peak force during the entry phase until the exit phase. The results show a significant difference in the behavior of the cutting process for a highly positive versus a highly negative cutting edge geometry. The negative edge geometry gives rise to larger force magnitudes and very similar developments of the tangential and radial cutting force. The positive cutting edge geometry produces considerably different developments of the tangential and radial cutting force. In case of positive cutting edge geometry, the radial cutting force increases while the uncut chip thickness decreases directly after the entry phase; reaching the peak value after a certain delay. The radial force fluctuation is significantly higher for the positive cutting edge geometry. The understanding of such behavior is important for modelling of the milling process, the design of the cutting edge and the interactive design of digital applications for the selection of the cutting parameters.

Place, publisher, year, edition, pages
Springer Nature Switzerland AG, 2019
Keywords
Milling, Cutting force, Cutting edge geometry, Frequency spectrum, RMS
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22349 (URN)10.1007/s12008-018-0513-5 (DOI)000468115700013 ()2-s2.0-85058211299 (Scopus ID)
Funder
Knowledge Foundation
Note

CC BY 4.0

© 2023 Springer Nature Switzerland AG. Part of Springer Nature.

This paper presents the results of a joint work between Seco Tools AB and University West in Sweden. Funding of the project, provided by Seco Tools and the KK foundation, is highly appreciated. Support from The Research School of Simulation and Control of Material affecting Processes, SiCoMaP is gratefully acknowledged.

Available from: 2023-03-31 Created: 2023-03-31 Last updated: 2023-03-31Bibliographically approved
Agic, A., Eynian, M., Ståhl, J.-E. & Beno, T. (2019). Experimental analysis of cutting edge effects on vibrations in end milling. CIRP - Journal of Manufacturing Science and Technology, 24, 66-74
Open this publication in new window or tab >>Experimental analysis of cutting edge effects on vibrations in end milling
2019 (English)In: CIRP - Journal of Manufacturing Science and Technology, ISSN 1755-5817, E-ISSN 1878-0016, Vol. 24, p. 66-74Article in journal (Refereed) Published
Abstract [en]

The ability to minimize vibrations in milling by the selection of cutting edge geometry and appropriate cutting conditions is an important asset in the optimization of the cutting process. This paper presents a measurement method and a signal processing technique to characterize and quantify the magnitude of the vibrations in an end milling application. Developed methods are then used to investigate the effects of various cutting edge geometries on vibrations in end milling. The experiments are carried out with five cutting edge geometries that are frequently used in machining industry for a wide range of milling applications. The results show that a modest protection chamfer combined with a relatively high rake angle has, for the most of cutting conditions, a reducing effect on vibration magnitudes. Furthermore, dynamics of a highly positive versus a highly negative cutting geometry is explored in time domain and its dependency on cutting conditions is presented. The results give concrete indications about the most optimal cutting edge geometry and cutting conditions in terms of dynamic behavior of the tool.

Place, publisher, year, edition, pages
Elsevier, 2019
Keywords
Milling, Acceleration, Cutting edge, Frequency spectrum, Rake angle, Chamfer
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22348 (URN)10.1016/j.cirpj.2018.11.001 (DOI)000460558000007 ()2-s2.0-85057229226 (Scopus ID)
Funder
Knowledge Foundation
Note

This paper presents the results of a joint work between Seco Tools AB and University West in Sweden. Funding of the project, provided by Seco Tools and the KK foundation, is highly appreciated. Support from The Research School of Simulation and Control of Material affecting Processes (SiCoMaP) is also gratefully acknowledged.

Available from: 2019-03-21 Created: 2023-03-31 Last updated: 2023-04-03Bibliographically approved
Devotta, A. M., Beno, T. & Eynian, M. (2019). Simulation-Based Product Development Framework for Cutting Tool Geometry Design. In: Dimiter Dimitrov; Devon Hagedorn-Hansen; Konrad von Leipzig (Ed.), International Conference on Competitive Manufacturing (COMA 19) Proceedings: 30 January 2019 – 1 February 2019 Stellenbosch, South Africa. Paper presented at International Conference on Competitive Manufacturing, COMA19, presented at Stellenbosch University, 30 January 2019 – 1 February 2019, Stellenbosch, South Africa (pp. 47-52). Stellenbosch University
Open this publication in new window or tab >>Simulation-Based Product Development Framework for Cutting Tool Geometry Design
2019 (English)In: International Conference on Competitive Manufacturing (COMA 19) Proceedings: 30 January 2019 – 1 February 2019 Stellenbosch, South Africa / [ed] Dimiter Dimitrov; Devon Hagedorn-Hansen; Konrad von Leipzig, Stellenbosch University , 2019, p. 47-52Conference paper, Published paper (Refereed)
Abstract [en]

Cutting tool geometry design has traditionally relied on experimental studies; while engineering simulations, to the level of industrial deployment, have been developed only in the last couple of decades. With the development of simulation capability across length scales from micro to macro,cutting tool geometry development includes engineering data development for its efficient utilization. This calls for the design of a simulation-based approach in the design of cutting tool geometry so that the engineering data can be generated for different machining applications (e.g.digital twin). In this study, the needs for engineering model development of different stages of cutting tool design evaluation is assessed. To this end, some of the previously developed engineering models have been evaluated for evaluation of chip form morphology in industrially relevant nose turning process, work piece material behavior modeling and damage modeling for the prediction of chip shape morphology. The study shows the possibility for the developed models to act as building blocks of a digital twin. It also shows the need for engineering model development for different aspects of cutting tool design, its advantages, limitations, and prospects.

Place, publisher, year, edition, pages
Stellenbosch University, 2019
Keywords
Product design, Simulation, Finite element method
National Category
Manufacturing, Surface and Joining Technology Production Engineering, Human Work Science and Ergonomics Other Mechanical Engineering
Identifiers
urn:nbn:se:his:diva-22350 (URN)978-0-7972-1779-9 (ISBN)
Conference
International Conference on Competitive Manufacturing, COMA19, presented at Stellenbosch University, 30 January 2019 – 1 February 2019, Stellenbosch, South Africa
Available from: 2020-01-15 Created: 2023-03-31 Last updated: 2023-03-31Bibliographically approved
Devotta, A. M., Beno, T., Siriki, R., Löf, R. & Eynian, M. (2017). Finite Element Modeling and Validation of Chip Segmentation in Machining of AISI 1045 Steel. Paper presented at 16th CIRP Conference on Modelling of Machining Operations (16th CIRP CMMO), 15-16 June 2017, Cluny, France. Procedia CIRP, 58, 499-504
Open this publication in new window or tab >>Finite Element Modeling and Validation of Chip Segmentation in Machining of AISI 1045 Steel
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2017 (English)In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 58, p. 499-504Article in journal (Refereed) Published
Abstract [en]

The finite element (FE) method based modeling of chip formation in machining provides the ability to predict output parameters like cutting forces and chip geometry. One of the important characteristics of chip morphology is chip segmentation. Majority of the literature within chip segmentation show cutting speed (vc) and feed rate (f) as the most influencing input parameters. The role of tool rake angle (α) on chip segmentation is limited and hence, the present study is aimed at understanding it. In addition, stress triaxiality’s importance in damage model employed in FE method in capturing the influence of α on chip morphology transformation is also studied. Furthermore, microstructure characterization of chips was carried out using a scanning electron microscope (SEM) to understand the chip formation process for certain cutting conditions. The results show that the tool α influences chip segmentation phenomena and that the incorporation of a stress triaxiality factor in damage models is required to be able to predict the influence of the α. The variation of chip segmentation frequency with f is predicted qualitatively but the accuracy of prediction needs improvement. © 2017 The Authors.

Place, publisher, year, edition, pages
Elsevier, 2017
Keywords
Cutting, Forecasting, Machining centers, Scanning electron microscopy, Shear stress, Chip morphologies, Chip segmentation, Cutting conditions, Damage model, Microstructure characterization, Output parameters, Stress triaxiality, Stress triaxiality factor, Finite element method
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22358 (URN)10.1016/j.procir.2017.03.259 (DOI)000404958500085 ()2-s2.0-85029738278 (Scopus ID)
Conference
16th CIRP Conference on Modelling of Machining Operations (16th CIRP CMMO), 15-16 June 2017, Cluny, France
Funder
Knowledge Foundation, 20110263, 20140130
Note

CC BY-NC-ND 4.0

The authors kindly acknowledge the financial support from Sandvik Coromant and the Knowledge Foundation through the Industrial Research School SiCoMaP, Dnr 20110263, 20140130.

Available from: 2017-12-13 Created: 2023-04-03 Last updated: 2023-04-03Bibliographically approved
Agic, A., Eynian, M., Hägglund, S., Ståhl, J.-E. & Beno, T. (2017). Influence of radial depth of cut on entry conditions and dynamics in face milling application. Journal of Superhard Materials, 39(4), 259-270
Open this publication in new window or tab >>Influence of radial depth of cut on entry conditions and dynamics in face milling application
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2017 (English)In: Journal of Superhard Materials, ISSN 1063-4576, Vol. 39, no 4, p. 259-270Article in journal (Refereed) Published
Abstract [en]

The choice of milling cutter geometry and appropriate cutting data for certain milling application is of vital importance for successful machining results. Unfavorable selection of cutting conditions might give rise to high load impacts that cause severe cutting edge damage. Under some circumstances the radial depth of cut in combination with milling cutter geometry might give unfavorable entry conditions in terms of cutting forces and vibration amplitudes. This phenomenon is originated from the geometrical features that affect the rise time of the cutting edge engagement into workpiece at different radial depths of cut. As the radial depth of cut is often an important parameter, particularly when machining difficult-to-cut materials, it is important to explore the driving mechanism behind vibrations generation. In this study, acceleration of the workpiece is measured for different radial depths of cut and cutting edge geometries. The influence of the radial depth of cut on the dynamical behavior is evaluated in time and frequency domains. The results for different radial depths of cut and cutting geometries are quantified using the root mean square value of acceleration. The outcome of this research study can be used both for the better cutting data recommendations and improved tool design.

Place, publisher, year, edition, pages
New York: Allerton Press, 2017
Keywords
milling entry, radial depth, cutting edge, cutting force, vibration
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22355 (URN)10.3103/S1063457617040062 (DOI)000409936100006 ()2-s2.0-85029210912 (Scopus ID)
Funder
Knowledge Foundation
Note

© 2023 Springer Nature Switzerland AG. Part of Springer Nature.

This paper presents the results of a joint work between Seco Tools AB and University West in Sweden. Funding of the project, provided by Seco Tools and the KK foundation, is highly appreciated. Support from The Research School of Simulation and Control of Material affecting Processes (SiCoMaP) is also gratefully acknowledged.

Available from: 2017-10-20 Created: 2023-04-03Bibliographically approved
Parsian, A., Magnevall, M., Beno, T. & Eynian, M. (2017). Sound Analysis in Drilling, Frequency and Time Domains. Paper presented at 16th CIRP Conference on Modelling of Machining Operations, CIRP CMMO 2017, Cluny, France, 15 June 2017 through 16 June 2017. Procedia CIRP, 58, 411-415
Open this publication in new window or tab >>Sound Analysis in Drilling, Frequency and Time Domains
2017 (English)In: Procedia CIRP, ISSN 2212-8271, E-ISSN 2212-8271, Vol. 58, p. 411-415Article in journal (Refereed) Published
Abstract [en]

This paper proposes a guideline for interpreting frequency content and time history of sound measurements in metal drilling processes. Different dynamic phenomena are reflected in generated sound in cutting processes. The footprint of such phenomena including torsional, lateral regenerative chatter and whirling in sound measurement results are discussed. Different indexable insert drills, at several cutting conditions, are covered. The proposed analysis could be used for studying, online monitoring and controlling of drilling processes. © 2017 The Authors.

Place, publisher, year, edition, pages
Elsevier, 2017
Keywords
Acoustic variables measurement, Architectural acoustics, Drilling, Machining centers, Vibration analysis, Chatter, Cutting conditions, Frequency and time domains, Frequency contents, Indexable inserts, Regenerative chatters, Sound analysis, Vibrations, Time domain analysis
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22366 (URN)10.1016/j.procir.2017.03.242 (DOI)000404958500070 ()2-s2.0-85029768891 (Scopus ID)
Conference
16th CIRP Conference on Modelling of Machining Operations, CIRP CMMO 2017, Cluny, France, 15 June 2017 through 16 June 2017
Funder
Knowledge Foundation
Note

CC BY-NC-ND 4.0

Available online 31 May 2017

This paper is the result of a joint project between Sandvik Coromant and University West, Sweden. Resources provided by SiCoMaP and the Knowledge Foundation (KK-stiftelsen) are greatly appreciated.

Available from: 2017-12-14 Created: 2023-04-04Bibliographically approved
Parsian, A., Magnevall, M., Eynian, M. & Beno, T. (2017). Time Domain Simulation of Chatter Vibrations in Indexable Drills. The International Journal of Advanced Manufacturing Technology, 89(1-4), 1209-1221
Open this publication in new window or tab >>Time Domain Simulation of Chatter Vibrations in Indexable Drills
2017 (English)In: The International Journal of Advanced Manufacturing Technology, ISSN 0268-3768, E-ISSN 1433-3015, Vol. 89, no 1-4, p. 1209-1221Article in journal (Refereed) Published
Abstract [en]

Regenerative chatter vibrations are common in drilling processes. These unwanted vibrations lead to considerable noise levels, damage the quality of the workpiece, and reduce tool life. The aim of this study is to simulate torsional and axial chatter vibrations as they play important roles in dynamic behavior of indexable insert drills with helical chip flutes. While asymmetric indexable drills are not the focal points in most of previous researches, this paper proposes a simulation routine which is adapted for indexable drills. Based on the theory of regenerative chatter vibration, a model is developed to include the asymmetric geometries and loadings that are inherent in the design of many indexable insert drills. Most indexable insert drills have two inserts located at different radial distances, namely central and peripheral inserts. Since the positions of the central and peripheral inserts are different, the displacement and thereby the change in chip thickness differs between the inserts. Additionally, the inserts have different geometries and cutting conditions, e.g., rake angle, coating, and cutting speed, which result in different cutting forces. This paper presents a time-domain simulation of torsional and axial vibrations by considering the differences in dynamics, cutting conditions, and cutting resistance for the central and peripheral inserts on the drill. The time-domain approach is chosen to be able to include nonlinearities in the model arising from the inserts jumping out of cut, multiple delays, backward motions of edges, and variable time delays in the system. The model is used to simulate cutting forces produced by each insert and responses of the system, in the form of displacements, to these forces. It is shown that displacements induced by dynamic torques are larger than those induced by dynamic axial forces. Finally, the vibration of a measurement point is simulated which is favorably comparable to the measurement results.

Place, publisher, year, edition, pages
Springer Nature Switzerland AG, 2017
Keywords
Chatter, Indexable insert drill, Time-domain
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22360 (URN)10.1007/s00170-016-9137-8 (DOI)000394500300097 ()2-s2.0-84979508770 (Scopus ID)
Funder
Knowledge Foundation
Note

CC BY 4.0

© 2023 Springer Nature Switzerland AG. Part of Springer Nature.

This paper presents the results of a joint work between Sandvik Coromant and University West in Sweden. Funding of the project provided by Sandvik Coromant and the KK foundation is highly appreciated. Support from The Research School of Simulation and Control of Material affecting Processes (SiCoMaP) is gratefully acknowledged. Contributions made by Tommy Gunnarsson at Sandvik Coromant in conducting the experiments are greatly appreciated.

Available from: 2015-12-01 Created: 2023-04-03 Last updated: 2023-04-04Bibliographically approved
Agic, A., Eynian, M., Hägglund, S., Ståhl, J.-E. & Beno, T. (2016). Influence of radial depth of cut on dynamics of face milling application. In: The 7th International Swedish Production Symposium, SPS16, Conference Proceedings: 25th – 27th of October 2016. Paper presented at 7th Swedish Production Symposium, SPS, Lund, October 25-27, 2016 (pp. 1-9). Lund: Swedish Production Academy
Open this publication in new window or tab >>Influence of radial depth of cut on dynamics of face milling application
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2016 (English)In: The 7th International Swedish Production Symposium, SPS16, Conference Proceedings: 25th – 27th of October 2016, Lund: Swedish Production Academy , 2016, p. 1-9Conference paper, Published paper (Refereed)
Abstract [en]

The choice of milling cutter geometry and appropriate cutting data for certain milling application is of vital importance for successful machining results. Unfavourable selection of cutting conditions might give rise to high load impacts that cause severe cutting edge damage. The radial depth of cut in combination with milling cutter geometry might under some circumstances give unfavourable entry conditions in terms of cutting forces and vibration amplitudes. This phenomenon originates from the geometrical features that affect the rise time of the cutting edge engagement into work piece at different radial depths of cut. As the radial depth of cut is often an important parameter, particularly when machining difficult to cut materials, it is important to explore the driving mechanism behind vibrations generation. In this study, acceleration of the work piece is measured for different radial depths of cut and cutting edge geometries. The influence of the radial depth of cut on the dynamical behaviour is evaluated in time and frequency domains. The results for different radial depths of cut and cutting geometries are quantified using root mean square value of acceleration. The outcome of this research study can be used both for the better cutting data recommendations and improved tool design.

Place, publisher, year, edition, pages
Lund: Swedish Production Academy, 2016
Keywords
Milling, entry, vibration
National Category
Manufacturing, Surface and Joining Technology
Identifiers
urn:nbn:se:his:diva-22367 (URN)
Conference
7th Swedish Production Symposium, SPS, Lund, October 25-27, 2016
Available from: 2016-12-07 Created: 2023-04-11 Last updated: 2023-04-11Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0003-0976-9820

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