A Quantitative Sensitivity Analysis of Cutting Performances in Orthogonal Machining with Restricted Contact and Flat-Faced Tools

2004 ◽  
Vol 126 (2) ◽  
pp. 408-411
Author(s):  
Ning Fang
Keyword(s):  
Sensitivity Analysis ◽  
Slip Line ◽  
Cutting Forces ◽  
Chip Thickness ◽  
Contact Length ◽  
Machining Parameters ◽  
Flow Angle ◽  
Orthogonal Machining ◽  
Different Types ◽  
Machining Operations

This paper presents a new quantitative sensitivity analysis of cutting performances in orthogonal machining with restricted contact and flat-faced tools, based on a recently developed slip-line model. Cutting performances are comprehensively measured by five machining parameters, i.e., the cutting forces, the chip back-flow angle, the chip up-curl radius, the chip thickness, and the tool-chip contact length. It is demonstrated that the percentage of contribution of tool-chip friction to the variation of cutting performances depends on different types of machining operations. No general conclusion about the effect of tool-chip friction should be made before specifying a particular type of machining operation and cutting conditions.

COMPLEXITY-BASED ANALYSIS OF THE INFLUENCE OF TOOL GEOMETRY ON CUTTING FORCES IN ROUGH END MILLING

Fractals ◽  
2018 ◽  
Vol 26 (05) ◽  
pp. 1850078 ◽  
Author(s):  
HAMIDREZA NAMAZI ◽  
ALI AKHAVAN FARID ◽  
CHANG TECK SENG
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
Fractal Structure ◽  
End Milling ◽  
Complex Structure ◽  
Tool Geometry ◽  
Machining Parameters ◽  
End Mill ◽  
Force Signal ◽  
Machining Operations

It is known that geometry of cutting tool affects the cutting forces in machining operations. In addition, the value of cutting forces changes during machining operations and creates a chaotic time series (signal). In this paper, we analyze the variations of the complex structure of cutting force signal in rough end milling operation using fractal theory. In fact, we analyze the variations of cutting force signal due to variations of tool geometry (square end mill versus serrated end mill). In case of each type of end mill, we did the machining operation in wet and dry conditions. Based on the results, the fractal structure of cutting force signal changes based on the type of milling tool. We also did the complexity analysis using approximate entropy to check the variations of the complexity of cutting force signal, where the similar behavior of variations between different conditions was obtained. The method of analysis that was used in this research can be applied to other machining operations to study the influence of different machining parameters on variations of fractal structure of cutting force.

scholarly journals A Slip-Line Field for Ploughing During Orthogonal Cutting

1998 ◽  
Vol 120 (4) ◽  
pp. 693-699 ◽  
Author(s):  
D. J. Waldorf ◽  
R. E. DeVor ◽  
S. G. Kapoor
Keyword(s):  
Slip Line ◽  
Cutting Forces ◽  
Orthogonal Cutting ◽  
Chip Thickness ◽  
Great Promise ◽  
Uncut Chip Thickness ◽  
Workpiece Material ◽  
Line Field ◽  
Slip Line Field ◽  
Edge Radius

Under normal machining conditions, the cutting forces are primarily due to the bulk shearing of the workpiece material in a narrow zone called the shear zone. However, under finishing conditions, when the uncut chip thickness is of the order of the cutting edge radius, a ploughing component of the forces becomes significant as compared to the shear forces. Predicting forces under these conditions requires an estimate of ploughing. A slip-line field is developed to model the ploughing components of the cutting force. The field is based on other slip-line fields developed for a rigid wedge sliding on a half-space and for negative rake angle orthogonal cutting. It incorporates the observed phenomena of a small stable build-up of material adhered to the edge and a raised prow of material formed ahead of the edge. The model shows how ploughing forces are related to cutter edge radius—a larger edge causing larger ploughing forces. A series of experiments were run on 6061-T6 aluminum using tools with different edge radii—including some exaggerated in size—and different levels of uncut chip thickness. Resulting force measurements match well to predictions using the proposed slip-line field. The results show great promise for understanding and quantifying the effects of edge radius and worn tool on cutting forces.

Mechanics of Orthogonal Machining: Predicting Chip Geometry and Cutting Forces from Work-Material Properties and Cutting Conditions

1969 ◽  
Vol 184 (1) ◽  
pp. 927-942 ◽  
Author(s):  
R. G. Fenton ◽  
P. L. B. Oxley
Keyword(s):  
Excellent Agreement ◽  
Material Properties ◽  
Cutting Forces ◽  
Contact Length ◽  
Experimental Results ◽  
Cutting Conditions ◽  
Orthogonal Machining ◽  
Work Material ◽  
Wide Range ◽  
Chip Geometry

A recently developed theory of orthogonal machining is used to calculate chip geometry (including tool-chip contact length) and cutting forces for SAE 1112 steel over a wide range of cutting conditions. A comparison with experimental results shows excellent agreement for most of the cutting conditions considered.

Mathematical Modeling of Cutting Forces in Microdrilling

2013 ◽  
Vol 135 (1) ◽  
Author(s):  
Kumar Sambhav ◽  
Puneet Tandon ◽  
Shiv G. Kapoor ◽  
Sanjay G. Dhande
Keyword(s):  
Mathematical Modeling ◽  
Slip Line ◽  
Cutting Forces ◽  
Chip Thickness ◽  
Rake Angle ◽  
Cutting Mechanism ◽  
Line Field ◽  
Slip Line Field ◽  
Effective Rake Angle ◽  
Secondary Cutting

In drilling, the primary and secondary cutting lips of the drill shear the material while the central portion of the chisel edge indents the workpiece, making the cutting process complex to understand. As we go for microdrilling, it exhibits an added complexity to the cutting mechanism as the edge radius gets comparable to chip thickness at low feeds. The presented work models the forces by the primary cutting lip of a microdrill analytically using slip-line field that includes the changes in the effective rake angle and dead metal cap during cutting for cases of shearing as well as ploughing. To study the variation of forces experimentally, the primary cutting lip and chisel edge forces are separated out by drilling through pilot holes of diameter slightly above the drill-web thickness. Finally, the analytical and experimental results are compared and the model is calibrated.

Investigation of Micro Scratching and Machining of Glass

2009 ◽  
Author(s):  
Mozhdeh Sajjadi ◽  
Mohammad Malekian ◽  
Simon S. Park ◽  
Martin B. G. Jun
Keyword(s):  
Cutting Forces ◽  
End Milling ◽  
Brittle Materials ◽  
Chip Thickness ◽  
Surface Characteristics ◽  
Soda Lime ◽  
Soda Lime Glass ◽  
Machining Parameters ◽  
Mechanical Removal ◽  
Mechanical Machining

Micro mechanical machining, which is mechanical removal of material using miniature tools, is one of the fabrication methods in the micro realm that has recently attracted a great deal of attention. Micro machining has the advantage of being able to machine complex shapes from brittle materials. The most challenging problem in the micro mechanical machining of brittle materials is the fabrication of fracture-free surfaces. To avoid brittle fractures, a thorough investigation is required to find the machining parameters in the ductile cutting regime, which is characterized by plastic deformation of material when the chip thickness is smaller than a critical value. In this study, the cutting forces and surface characteristics of soda-lime glass are examined. Conical scratch tests are performed to identify the critical chip thickness, and the cutting forces in the ductile regime are modeled. In addition, torus end milling of glass is performed to examine the effects of feed rates, and spindle speeds, and to investigate tool wear.

IMPROVING THE EFFICIENCY OF MILLING HOLES WITH A SMALL-SIZED TOOL IN THE CONDITIONS OF AUTOMATED PRODUCTION

2021 ◽  
Vol 2021 (10) ◽  
pp. 13-21
Author(s):  
Vladimir Davydov ◽  
Aleksandr Nikitenko ◽  
Mihail Gimadeev ◽  
Vera Berkun
Keyword(s):  
Cutting Forces ◽  
Small Diameter ◽  
Machining Parameters ◽  
Optimal Range ◽  
Helix Pitch ◽  
Key Factor ◽  
End Mills ◽  
Tool Strength ◽  
Machining Operations ◽  
Cutting Modes

The purpose of the paper. In order to solve the problems of increasing the efficiency of machining operations of small diameter holes by milling, the optimal range of cutting modes and helix pitch for the machining strategy with helical interpolation is established. The reduction of labor intensity and costs of hole machining when treating holes in alloyed corrosion-resistant steels is experimentally confirmed. Research methods. In this paper, the issues of machining blind holes by helical interpolation milling with end cylindrical carbide cutters of relatively small dimensions in parts made of 12X18N10T alloy are considered. The features of this machining are availability of significant axial and radial components of the cutting forces with relatively low tool strength. This leads to the fact that a key factor of the tool failure is its mechanical failure, the cause of which is an increase in cutting forces due to the edge of the cutter being chipped. Research results and novelty. It has been experimentally proved that the most rational machining parameters to ensure the specified accuracy and surface quality of the machined holes when using a strategy of helical interpolation milling will be the choice of the helix pitch p = 0.2 mm, the feed range F = 0.075-0.11 mm /tooth, which corresponds to the minute feeds of the milling center 450-675 mm/min. Conclusions. The optimal range of cutting modes is found in the feed range from 450 to 675 mm/min, with a helical interpolation pitch of 0.2 mm. The accuracy and roughness of the holes obtained by milling with end mills with a diameter of 3 mm for steel 12X18N10T is evaluated.

SLIP-LINE MODELING OF MACHINING AND DETERMINE THE INFLUENCE OF RAKE ANGLE ON THE CUTTING FORCE

2012 ◽  
Vol 36 (1) ◽  
pp. 23-35 ◽  
Author(s):  
Sabri Ozturk
Keyword(s):  
Cutting Force ◽  
Slip Line ◽  
Cutting Forces ◽  
Orthogonal Cutting ◽  
Chip Thickness ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Uncut Chip Thickness ◽  
Thrust Forces ◽  
Model Approach

In this study, the effects of the rake angle on main cutting force (Fc), and thrust forces (Ft) was investigated. A new slip line model approach for modelling the orthogonal cutting process was proposed. This model was applied at negative rake angles from 0° to –60° and consists of three regions. The main forces were measured with a computer aided quick stop device. Variance Analysis (ANOVA) was utilized to analyze the effects of the cutting parameters on cutting and thrust forces accordingly. Multi-variable regression analysis was also employed to determine the correlations between the factors and the cutting forces. The cutting forces could be calculated by equation parameters which are the rake angle and the uncut chip thickness.

Experimental investigation of a slip-line field model for a worn cutting tool

2013 ◽  
Vol 228 (8) ◽  
pp. 1398-1404 ◽  
Author(s):  
Alper Uysal ◽  
Erhan Altan
Keyword(s):  
Wear Rate ◽  
Slip Line ◽  
Field Model ◽  
Cutting Tool ◽  
Flank Wear ◽  
Cutting Speed ◽  
Chip Thickness ◽  
Rake Angle ◽  
Uncut Chip Thickness ◽  
Line Field

In this study, the slip-line field model developed for orthogonal machining with a worn cutting tool was experimentally investigated. Minimum and maximum values of five slip-line angles ( θ1, θ2, δ2, η and ψ) were calculated. The friction forces that were caused by flank wear land, chip up-curl radii and chip thicknesses were calculated by solving the model. It was specified that the friction force increased with increase in flank wear rate and uncut chip thickness and it decreased a little with increase in cutting speed and rake angle. The chip up-curl radius increased with increase in flank wear rate and it decreased with increase in uncut chip thickness. The chip thickness increased with increase in flank wear rate and uncut chip thickness. Besides, the chip thickness increased with increase in rake angle and it decreased with increase in cutting speed.

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