Edge Radius Variability and Force Measurement Considerations

1999 ◽  
Vol 122 (3) ◽  
pp. 590-593 ◽  
Author(s):  
Roy J. Schimmel ◽  
Jairam Manjunathaiah ◽  
William J. Endres
Keyword(s):  
Measurement Errors ◽  
Thrust Force ◽  
Force Measurement ◽  
Orthogonal Cutting ◽  
Cutting Tools ◽  
White Light Interferometry ◽  
Machining Forces ◽  
Edge Radius ◽  
Cutting Inserts ◽  
The Difference

A new, noncontact instrument, based on white light interferometry, is used to measure the edge radii of cutting tools with measurement errors of less than 3 μm. Edges of several commercial cutting inserts are measured and compared. It is found that the radius of the hone varies along the length of the edge in a parabolic manner. The difference between the edge radius at the center of the edge and the radius at the start of the corner can be as large as 25 μm (0.001 in). The variation between the edges on an insert and across inserts in a batch of tools can be as high as 25 μm (0.001 in). Statistically significant variations are also seen in the corner radius region in which much cutting occurs in turning, boring and face milling processes. Orthogonal cutting tests with tools of measured edge radius in the zone of cut indicate that the machining forces, especially the thrust force component, are sensitive to changes in edge radius on the order of measured variations. [S1087-1357(00)01603-8]

Influence of Reground Tool Sharpness on Micro-Cutting Process

2010 ◽  
Vol 37-38 ◽  
pp. 550-553
Author(s):  
Xin Li Tian ◽  
Zhao Li ◽  
Xiu Jian Tang ◽  
Fang Guo ◽  
Ai Bing Yu
Keyword(s):  
Cutting Forces ◽  
Orthogonal Cutting ◽  
Cutting Tools ◽  
Chip Thickness ◽  
Cutting Edge ◽  
Cutting Process ◽  
Micro Cutting ◽  
Temperature Distributions ◽  
Edge Radius ◽  
1045 Steel

Tool edge radius has obvious influences on micro-cutting process. It considers the ratio of the cutting edge radius and the uncut chip thickness as the relative tool sharpness (RST). FEM simulations of orthogonal cutting processes were studied with dynamics explicit ALE method. AISI 1045 steel was chosen for workpiece, and cemented carbide was chosen for cutting tool. Sixteen cutting edges with different RTS values were chosen for analysis. Cutting forces and temperature distributions were calculated for carbide cutting tools with these RTS values. Cutting edge with a small RTS obtains large cutting forces. Ploughing force tend to sharply increase when the RTS of the cutting edge is small. Cutting edge with a reasonable RTS reduces the heat generation and presents reasonable temperature distributions, which is beneficial to cutting life. The force and temperature distributions demonstrate that there is a reasonable RTS range for the cutting edge.

Assessment of Restricted Contact Cutting Tool in Dry Machining of AISI 1045 Steel

2014 ◽  
Author(s):  
J. Ma ◽  
Xianchen Ge ◽  
Nick H. Duong ◽  
Shuting Lei
Keyword(s):  
Cutting Force ◽  
Cutting Tool ◽  
Thrust Force ◽  
Alpha Angle ◽  
Cutting Tools ◽  
Rake Face ◽  
Edge Radius ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel

This paper studies the performance of restricted cutting tool in dry orthogonal machining of mild steel (AISI 1045 steel) using finite element simulations. The rake face of cemented carbide (WC/Co) cutting inserts is designed and the rake face length is shortened. The purpose is to examine the effect of shortened tools on machining performance and to compare it with regular cutting tools. The following restricted tool parameters are examined: length of rake face, alpha angle (the angle between the rake face and the supporting face), and edge radius. Their effects are assessed in terms of the main force, thrust force, and chip-tool contact length. It is found that restricted cutting tools generate lower cutting force and thrust force and consequently lower the energy necessary for machining. The length of rake face, the angle between the rake face and the supporting face, and edge radius all have influence on cutting force in their own ways. The effects of these three parameters on the tool temperature distribution are also investigated.

Comparison Research on the Machinability of Hardened Steel when Dry Turning with Ceramic and CBN Cutting Tools

2010 ◽  
Vol 43 ◽  
pp. 573-577 ◽  
Author(s):  
Chun Juan Tu ◽  
Xu Hong Guo ◽  
Wei Wang ◽  
Chi Hong Wang
Keyword(s):  
Cutting Forces ◽  
Thrust Force ◽  
Linear Regression Analysis ◽  
Tangential Force ◽  
Cutting Tools ◽  
Cutting Parameters ◽  
Hardened Steel ◽  
Dry Turning ◽  
Comparison Research ◽  
The Difference

Researching on dry turning hardened steel was to replace the grinding with turning, which would improve efficiency and reduce cost. The contrast experiments of turning hardened steel with ceramic and CBN cutting tools were carried out. The cutting forces of two tools with different cutting parameters were measured by Kistler cutting force acquisition system. The difference with two chips was observed by scanning electron microscope(SEM). The experimental equations of cutting forces were built up by the linear regression analysis method. The results indicated that the variation trend of cutting forces with ceramic and CBN cutting tools in same conditions was same. The thrust force was maximal, next was tangential force, axial force was minimum. The thrust force and tangential force of ceramic cutting tools were almost double compared with CBN cutting tools. The shapes of chips with ceramic and CBN cutting tools were saw-tooth, the rough slice layer with periodic flow was shown on outer surface and the friction mask was distributed well-proportioned on inner surface. The spacing of rough slice layer of chips with CBN cutting tools was more wide, the friction mask of chips with ceramic cutting tools was more clear.

Tool-Work Thermocouple Temperature Measurements—Theory and Implementation Issues

1993 ◽  
Vol 115 (4) ◽  
pp. 432-437 ◽  
Author(s):  
D. A. Stephenson
Keyword(s):  
Measurement Errors ◽  
Cutting Tools ◽  
Electrical Potential ◽  
Temperature Measurements ◽  
Theoretical Understanding ◽  
Machining System ◽  
Thermocouple Method ◽  
The Difference ◽  
Thermocouple Temperature ◽  
Tools Wear

Since cutting tools wear by temperature-activated mechanisms, it would be desirable to make tool temperature measurements during machinability tests. However, none of the laboratory methods for measuring temperatures reported in the literature is simple and reliable enough for routine testing. The method which is most promising is the tool-work thermocouple method, which yields a repeatable result which correlates well with tool wear for many materials. This method is not normally used in machinability testing because it is not clear what temperature the method actually measures and because, as conventionally described, it cannot be used for roughing cuts at high cutting speeds. The purpose of this paper is to extend both the theoretical understanding and range of application of the tool-work thermocouple method. The question of what temperature is measured by the method is answered by analyzing the electrical potential distribution in a cutting tool due to a distributed interfacial emf. It is shown that in general the tool-work thermocouple temperature differs from the average interfacial temperature, but that for tungsten carbide tools the difference is usually small. The isolation of the tool-work thermocouple circuit is also considered. Methods of measuring signals without introducing insulation between the chuck and workpiece and reducing the machining system stiffness are described. Finally, methods of minimizing measurement errors due to secondary junctions are discussed. Sample signals from machinability tests on steels are used to illustrate significant points.

Experimental and Numerical Investigation into Residual Stress During Turning Operation for Stainless Steel AISI 316

2020 ◽  
Vol 38 (12A) ◽  
pp. 1862-1870
Author(s):  
Safa M. Lafta ◽  
Maan A. Tawfiq
Keyword(s):  
Stainless Steel ◽  
Residual Stresses ◽  
Orthogonal Cutting ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Percentage Error ◽  
Depth Of Cut ◽  
Main Role ◽  
Turning Operation ◽  
Aisi 316

RS (residual stresses) represent the main role in the performance of structures and machined parts. The main objective of this paper is to investigate the effect of feed rate with constant cutting speed and depth of cut on residual stresses in orthogonal cutting, using Tungsten carbide cutting tools when machining AISI 316 in turning operation. AISI 316 stainless steel was selected in experiments since it is used in many important industries such as chemical, petrochemical industries, power generation, electrical engineering, food and beverage industry. Four feed rates were selected (0.228, 0.16, 0.08 and 0.065) mm/rev when cutting speed is constant 71 mm/min and depth of cutting 2 mm. The experimental results of residual stresses were (-15.75, 12.84, 64.9, 37.74) MPa and the numerical results of residual stresses were (-15, 12, 59, and 37) MPa. The best value of residual stresses is (-15.75 and -15) MPa when it is in a compressive way. The results showed that the percentage error between numerical by using (ABAQUS/ CAE ver. 2017) and experimental work measured by X-ray diffraction is range (2-15) %.

scholarly journals Feasibility of Cobalt-Free Nanostructured WC Cutting Inserts for Machining of a TiC/Fe Composite

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3432
Author(s):  
Edwin Gevorkyan ◽  
Mirosław Rucki ◽  
Tadeusz Sałaciński ◽  
Zbigniew Siemiątkowski ◽  
Volodymyr Nerubatskyi ◽  
...  
Keyword(s):  
Cubic Boron Nitride ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Machined Surface ◽  
Powder Consolidation ◽  
Plasma Sintering ◽  
Cutting Inserts ◽  
Spark Plasma ◽  
And Performance ◽  
Nanostructured Tungsten Carbide

The paper presents results of investigations on the binderless nanostructured tungsten carbide (WC) cutting tools fabrication and performance. The scientific novelty includes the description of some regularities of the powder consolidation under electric current and the subsequent possibility to utilize them for practical use in the fabrication of cutting tools. The sintering process of WC nanopowder was performed with the electroconsolidation method, which is a modification of spark plasma sintering (SPS). Its advantages include low temperatures and short sintering time which allows retaining nanosize grains of ca. 70 nm, close to the original particle size of the starting powder. In respect to the application of the cutting tools, pure WC nanostructure resulted in a smaller cutting edge radius providing a higher quality of TiC/Fe machined surface. In the range of cutting speeds, vc = 15–40 m/min the durability of the inserts was 75% of that achieved by cubic boron nitride ones, and more than two times better than that of WC-Co cutting tools. In additional tests of machining 13CrMo4 material at an elevated cutting speed of vc = 100 m/min, binderless nWC inserts worked almost three times longer than WC-Co composites.

scholarly journals THE VALUE OF ROBUST STATISTICAL FORECASTS IN THE COVID-19 PANDEMIC

2021 ◽  
Vol 256 ◽  
pp. 19-43
Author(s):  
Jennifer L. Castle ◽  
Jurgen A. Doornik ◽  
David F. Hendry
Keyword(s):  
Structural Change ◽  
Measurement Errors ◽  
Epidemiological Models ◽  
Short Term ◽  
Data Measurement ◽  
Policy Interventions ◽  
Changing Trends ◽  
Technological Advances ◽  
The Difference ◽  
The Uk

The Covid-19 pandemic has put forecasting under the spotlight, pitting epidemiological models against extrapolative time-series devices. We have been producing real-time short-term forecasts of confirmed cases and deaths using robust statistical models since 20 March 2020. The forecasts are adaptive to abrupt structural change, a major feature of the pandemic data due to data measurement errors, definitional and testing changes, policy interventions, technological advances and rapidly changing trends. The pandemic has also led to abrupt structural change in macroeconomic outcomes. Using the same methods, we forecast aggregate UK unemployment over the pandemic. The forecasts rapidly adapt to the employment policies implemented when the UK entered the first lockdown. The difference between our statistical and theory based forecasts provides a measure of the effect of furlough policies on stabilising unemployment, establishing useful scenarios had furlough policies not been implemented.

scholarly journals Effect of Cutting Parameters and Tool Geometry on the Performance Analysis of One-Shot Drilling Process of AA2024-T3

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 854
Author(s):  
Muhammad Aamir ◽  
Khaled Giasin ◽  
Majid Tolouei-Rad ◽  
Israr Ud Din ◽  
Muhammad Imran Hanif ◽  
...  
Keyword(s):  
Feed Rate ◽  
Surface Defects ◽  
Thrust Force ◽  
Cutting Tools ◽  
Chip Thickness ◽  
Cutting Parameters ◽  
Spindle Speed ◽  
Machining Process ◽  
Tool Geometry ◽  
Drilling Process

Drilling is an important machining process in various manufacturing industries. High-quality holes are possible with the proper selection of tools and cutting parameters. This study investigates the effect of spindle speed, feed rate, and drill diameter on the generated thrust force, the formation of chips, post-machining tool condition, and hole quality. The hole surface defects and the top and bottom edge conditions were also investigated using scan electron microscopy. The drilling tests were carried out on AA2024-T3 alloy under a dry drilling environment using 6 and 10 mm uncoated carbide tools. Analysis of Variance was employed to further evaluate the influence of the input parameters on the analysed outputs. The results show that the thrust force was highly influenced by feed rate and drill size. The high spindle speed resulted in higher surface roughness, while the increase in the feed rate produced more burrs around the edges of the holes. Additionally, the burrs formed at the exit side of holes were larger than those formed at the entry side. The high drill size resulted in greater chip thickness and an increased built-up edge on the cutting tools.

Total Pressure Correction of a Sub-Miniature Five-Hole Probe in Areas of Pressure Gradients

2012 ◽  
Author(s):  
J. Town ◽  
A. Akturk ◽  
C. Camcı
Keyword(s):  
Pressure Measurement ◽  
Measurement Errors ◽  
Total Pressure ◽  
Pressure Gradients ◽  
Pressure Data ◽  
Flow Conditions ◽  
Complex Flow ◽  
Ducted Fan ◽  
The Difference ◽  
Best Fit

Five-hole probes, being a dependable and accurate aerodynamic tools, are excellent choices for measuring complex flow fields. However, total pressure gradients can induce measurement errors. The combined effect of the different flow conditions on the ports causes the measured total pressure to be prone to a greater error. This paper proposes a way to correct the total pressure measurement. The correction is based on the difference between the measured total pressure data of a Kiel probe and a sub-miniature prism-type five-hole probe. By comparing them in a ducted fan related flow field, a line of best fit was constructed. The line of best fit is dependent on the slope of the line in a total pressure versus span and difference in total pressure between the probes at the same location. A computer program, performs the comparison and creates the correction equation. The equation is subsequently applied to the five-hole probe total pressure measurement, and the other dependent values are adjusted. The validity of the correction is then tested by placing the Kiel probe and the five-hole probe in ducted fans with a variety of different tip clearances.

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