The Mechanism of Chatter Vibration in a Spindle-Workpiece System: Part 1—Properties of Self-Excited Chatter Vibration in Spindle-Workpiece System

1988 ◽  
Vol 110 (3) ◽  
pp. 236-241 ◽  
Author(s):  
E. Marui ◽  
S. Kato ◽  
M. Hashimoto ◽  
T. Yamada
Keyword(s):  
Cutting Force ◽  
Energy Supply ◽  
Phase Lag ◽  
Chatter Vibration ◽  
Regenerative Chatter ◽  
Phase Lags ◽  
System Part ◽  
Cutting Operation ◽  
Dynamic Rigidity ◽  
Chatter Marks

The elimination of chatter vibration is important to improve cutting accuracy and to improve productivity of the cutting operation. In this study, the characteristics of the primary and regenerative chatter vibration occurring in the spindle-workpiece system are investigated experimentally using six spindle-workpiece systems having different vibratory properties. The vibratory locus of the spindle-workpiece system is found. The phase lag between the cutting force and chatter displacement and the phase lag between the successive chatter marks are obtained quantitatively. These phase lags are closely related to the energy supply. The chatter vibration hardly grows up in the spindle-workpiece system having large dynamic rigidity.

The Mechanism of Chatter Vibration in a Spindle-Workpiece System: Part 3—Analytical Considerations

1988 ◽  
Vol 110 (3) ◽  
pp. 248-253 ◽  
Author(s):  
E. Marui ◽  
S. Kato ◽  
M. Hashimoto ◽  
T. Yamada
Keyword(s):  
Cutting Force ◽  
Rake Angle ◽  
Velocity Variation ◽  
Damping Capacity ◽  
Phase Lag ◽  
Chatter Vibration ◽  
Dynamic Variations ◽  
Cutting Velocity ◽  
System Part ◽  
Chatter Marks

Chatter vibration occurring in the spindle-workpiece system of a lathe is treated theoretically, considering the phase lag of cutting force and chatter marks, the dynamic variation effects on cutting force of cutting velocity, and the rake angle during vibration. As a result, it is clarified that the chatter vibration is mainly induced by the phase lag of cutting force (primary chatter) and by the phase lag of chatter marks in successive cutting (regenerative chatter). The dynamic variations of the cutting velocity and rake angle make the spindle-workpiece system more unstable under vibration. The effect of cutting velocity variation is more remarkable than that of rake angle in both types of chatter. Chatter vibration can effectively be suppressed by enlarging the damping capacity of the system.

The Mechanism of Chatter Vibration in a Spindle-Workpiece System: Part 2—Characteristics of Dynamic Cutting Force and Vibration Energy

1988 ◽  
Vol 110 (3) ◽  
pp. 242-247 ◽  
Author(s):  
E. Marui ◽  
S. Kato ◽  
M. Hashimoto ◽  
T. Yamada
Keyword(s):  
Cutting Force ◽  
Rake Angle ◽  
Dynamic State ◽  
Phase Lag ◽  
Chatter Vibration ◽  
Vibration Displacement ◽  
Dynamic Variations ◽  
Dynamic Cutting Force ◽  
Cutting Velocity ◽  
System Part

The cutting force acting in the dynamic state of a lathe spindle-workpiece system is affected by the dynamic variations of cutting depth, cutting velocity, and rake angle. In this study, the influences of these parameters on the dynamic cutting force are measured by unique experiments. The phase lag between the dynamic cutting force and vibration displacement is clarified under various cutting conditions. The dynamic cutting force when the cutting velocity and the rake angle are dynamically changed is measured, and the results are represented as the cutting velocity coefficients and the rake angle coefficients. Based on these results, the energy supplied by the dynamic cutting force is obtained and the mechanism by which the chatter vibration occurs is discussed.

On the Cause of Regenerative Chatter Due to Workpiece Deflection

1974 ◽  
Vol 96 (1) ◽  
pp. 179-186 ◽  
Author(s):  
S. Kato ◽  
E. Marui
Keyword(s):  
Differential Equation ◽  
Experimental Results ◽  
Phase Lag ◽  
Chatter Vibration ◽  
Transient Vibration ◽  
Regenerative Chatter ◽  
Work Surface ◽  
Chatter Vibrations

The cause and the mechanism of regenerative chatter vibrations due to the deflection of workpiece occurring in machining metals are investigated experimentally. The regenerative chatter vibration is induced by the phase lag of the undulations in successive cutting. This means that small undulations initially produced on a work surface by the transient vibration of the workpiece become larger and the undulations extend over the whole work surface because a given amount of energy is available for exciting or maintaining the vibration owing to the phase lag of successive undulations. Then, a differential equation of chatter vibration is introduced based on the experimental results, and some remarks on the properties of chatter vibration are given.

Regenerative Chatter Vibration Occurring in Turning With Different Side Cutting Edge Angles

1995 ◽  
Vol 117 (4) ◽  
pp. 551-558 ◽  
Author(s):  
E. Marui ◽  
M. Hashimoto ◽  
S. Kato
Keyword(s):  
Energy Supply ◽  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Edge ◽  
The Other ◽  
Chatter Vibration ◽  
Regenerative Chatter ◽  
Edge Angle ◽  
Regenerative Effect ◽  
Two Factors

This paper deals with the regenerative chatter vibration occurring in cutting tools with different side cutting edge angles. The occurrence of regenerative chatter vibration of the cutting tool is influenced by two factors, which are closely related to the vibratory energy supply or consumption. One factor is the interference effect between the tool flank and the workpiece. Of course, this factor exists in the primary chatter, too. The other is the regenerative effect. The influence of both factors on the regenerative chatter vibration of cutting tools with different side cutting edge angles is examined experimentally. The vibratory energy supply is simulated, considering the dynamic cutting process. As a result, the property of the regenerative chatter vibration and the influence of the side cutting edge angle on the regenerative chatter vibration are clarified.

Predictive Modeling of Nonlinear Regenerative Chatter via Measurement, Analysis, and Simulation

1999 ◽  
Author(s):  
J. R. Pratt ◽  
M. A. Davies ◽  
M. D. Kennedy ◽  
T. Kalmár-Nagy
Keyword(s):  
Cutting Force ◽  
Initial Conditions ◽  
Stability Boundary ◽  
Chip Thickness ◽  
Cutting Parameters ◽  
Computational Techniques ◽  
Regenerative Chatter ◽  
Stability Lobe ◽  
Measurement Analysis ◽  
On Chip

Abstract A single-degree-of-freedom active cutting fixture is employed to reveal and analyse the hysteretic nature of the lobed stability boundary in a simple machining experiment. Specifically, the seventh stability lobe of a regenerative cutting process is mapped using experimental, analytical, and computational techniques. Then, taking width of cut as a control parameter, the transition from stable cutting to chatter is observed experimentally. The cutting stability is found to possess a substantial hysteresis so that either stable or chattering tool motions can exist at the same nominal cutting parameters, depending on initial conditions. This behavior is predicted by applying nonlinear regenerative chatter theory to an empirical characterization of the cutting force dependence on chip thickness. Time-domain simulations that incorporate both the nonlinear cutting force dependence on chip thickness and the multiple-regenerative effect due to the tool leaving the cut are shown to agree both qualitatively and quantitatively with experiment.

Suppression of regenerative chatter vibration in simultaneous double-sided milling of flexible plates by speed difference

CIRP Annals ◽  
2010 ◽  
Vol 59 (1) ◽  
pp. 387-390 ◽  
Author(s):  
E. Shamoto ◽  
T. Mori ◽  
K. Nishimura ◽  
T. Hiramatsu ◽  
Y. Kurata
Keyword(s):  
Chatter Vibration ◽  
Regenerative Chatter ◽  
Speed Difference ◽  
Flexible Plates

Locomotion in Burrowing and Vagrant Wolf Spiders (Lycosidae)

1981 ◽  
Vol 92 (1) ◽  
pp. 305-321 ◽  
Author(s):  
T. M. WARD ◽  
W. F. HUMPHREYS
Keyword(s):  
Wolf Spider ◽  
The Body ◽  
Power Stroke ◽  
Phase Lag ◽  
Running Speed ◽  
Wolf Spiders ◽  
High Speeds ◽  
Phase Lags ◽  
The Relationship

Locomotion in the vagrant wolf spider Trochosa ruricola is compared to that in the burrow dwelling wolf spider Lycosa tarentula (Araneae: Lycosidae). L. tarentula takes relatively shorter steps than T. ruricola. At high speeds T. ruricola approximates an alternating tetrapod gait but this does not occur in L. tarentula. Phase lag differs between species and varies marginally with speed except for ipsilateral phase lags in L. tarentula which are erratic if they include leg 1. In both species the protraction/retraction ratio is directly related to both running speed and stepping frequency, but the relationship is more marked in L. tarentula. The protraction/retraction ratio is more variable in leg 1 and varies between legs along the body but by a greater amount in L. tarentula. In these spiders, in contrast to the situation in many insects, both the duration of protraction and retraction show marked inverse relationships to stepping frequency. The power stroke (retraction) occupies a variable proportion of the stepping cycle, which is not the case in other spiders, and this proportion is lower than for other spiders. It is suggested that the first pair of legs is used more for sensory than for locomotory purpose and that this is more marked in the burrow dwelling species, L. tarentula.

Ocean Tides near Hawaii from Satellite Altimeter Data. Part I

2021 ◽  
Vol 38 (5) ◽  
pp. 937-949
Author(s):  
Minjie Xu ◽  
Yuzhe Wang ◽  
Shuya Wang ◽  
Xianqing Lv ◽  
Xu Chen
Keyword(s):  
Chebyshev Polynomials ◽  
Least Squares Method ◽  
Altimeter Data ◽  
Phase Lag ◽  
Tidal Amplitude ◽  
Physical Processes ◽  
Satellite Altimeter ◽  
Polynomial Coefficients ◽  
Phase Lags ◽  
Satellite Altimeter Data

AbstractSufficient and accurate tide data are essential for analyzing physical processes in the ocean. A method is developed to spatially fit the tidal amplitude and phase lag data along satellite altimeter tracks near Hawaii and construct reliable cotidal charts by using the Chebyshev polynomials. The method is completely dependent on satellite altimeter data. By using the cross-validation method, the optimal orders of Chebyshev polynomials are determined and the polynomial coefficients are calculated by the least squares method. The tidal amplitudes and phase lags obtained by the method are compared with those from the Finite Element Solutions 2014 (FES2014), National Astronomical Observatory 99b (NAO.99b), and TPXO9 models. Results indicate that the method yields accurate results as its fitting results are consistent with the harmonic constants of the three models. The feasibility of this method is also validated by the harmonic constants from tidal gauges near Hawaii.

Performance Evaluation of PVD and CVD Coated Inserts during End Milling with DRY and MQL Condition

2017 ◽  
Vol 867 ◽  
pp. 165-170
Author(s):  
Isha Srivastava ◽  
Ajay Batish
Keyword(s):  
Tool Wear ◽  
Cutting Force ◽  
End Milling ◽  
Cutting Speed ◽  
Minimum Quantity Lubrication ◽  
Sem Analysis ◽  
Depth Of Cut ◽  
High Cutting Speed ◽  
Cutting Operation ◽  
En 31

The aim of this study were to evaluate the performance of PVD (TiAlN+TiN) and CVD (TiCN+Al2O3+TiN) coated inserts in end milling of EN–31 hardened die steel of 43±1 HRC during dry and MQL (Minimum quantity lubrication) machining. The experiments were conducted at a fixed feed rate, depth of cut and varying cutting speed to measure the effect of cutting speed on cutting force and tool wear of CVD and PVD-coated inserts. The performance of CVD and PVD-coated inserts under dry and MQL condition by measuring the tool wear and cutting force were compared. During cutting operation, it was noticed that PVD inserts provide less cutting force and tool wear as compared to the CVD inserts under both dry as well as the MQL condition because PVD inserts have a thin insert coating and CVD inserts have a thick insert coating, but PVD inserts experience catastrophic failure during cutting operation whereas CVD inserts have a capability for continuous machining under different machining. Tool wear has measured by SEM analysis. The result shows that MQL machining provides the optimum results as compared to the dry condition. MQL machining has the ability to work under high cutting speed. As the cutting speed increases the performance of dry machining was decreased, but in MQL machining, the performance of the inserts was increased with increases of cutting speed. MQL machining generates less cutting force on the cutting zone and reduces the tool wear which further increase the tool life.

Sign in / Sign up

Export Citation Format

Share Document