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Article
Publication date: 1 April 2002

W.F. Sales, G. Guimarães, Á.R. Machado and E.O. Ezugwu

Many machining researches are focused on cutting tools mainly due to the wear developed as a result of high temperatures generated that accelerate thermally related wear…

Abstract

Many machining researches are focused on cutting tools mainly due to the wear developed as a result of high temperatures generated that accelerate thermally related wear mechanisms, consequently reducing tool life. Cutting fluids are used in machining operations to minimize cutting temperature although there is no available indicator of their cooling ability. In this study, a method to determine the cooling ability of cutting fluids is proposed. A thermocouple technique was used to verify the chip‐tool interface temperature of various cutting fluids during turning operation. The method consists of measuring the temperature drop from 300°C up to room temperature after heating a standardised AISI 8640 workpiece and fixing it to the chuck of a lathe and with a constant spindle speed of 150 rpm the cutting fluid was applied to a specific point. The temperature was measured and registered by an infrared thermosensor with the aid of an AC/DC data acquisition board and a PC. The convective heat exchange coefficient, h, was determined and used to classify the cooling ability of the cutting fluids. The machining tests showed that the application of the fluid with better cooling ability will not always guarantee lower chip‐tool interface temperature.

Details

Industrial Lubrication and Tribology, vol. 54 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 20 July 2010

M.Q. Al‐Odat

The purpose of this paper is to conduct a full three‐dimensional numerical analysis to simulate the thermal behavior of high speed steel (HSS) cutting tool, with…

Abstract

Purpose

The purpose of this paper is to conduct a full three‐dimensional numerical analysis to simulate the thermal behavior of high speed steel (HSS) cutting tool, with temperature dependent thermal properties, in dry machining with embedded heat pipe (HP), and investigate the effects of HP installation, variable thermal properties, generated heat flux and cutting speed.

Design/methodology/approach

The heat transfer equation used to predict cutting tool temperature is parabolic partial differential equation. Grid points including independent variables are initially formed in solution of partial differential equation by finite element method (FEM). In this paper, one‐dimensional heat transfer equation with variable thermophysical properties is solved by FEM.

Findings

In this paper, the heat transfer equation in cutting tool is solved for variable thermophysical properties and the temperature field and temperature history are obtained. Variable thermophysical properties are considered to display the temperature fields in the cutting tool.

Originality/value

A full three‐dimensional numerical analysis is conducted to simulate the thermal behavior of HSS cutting tool, with temperature dependent thermal properties, in dry machining with embedded HP. The heat conduction equation is solved by FEM analysis.

Details

Engineering Computations, vol. 27 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 17 June 2020

Srinath Sridhar and Rajeswari Sellamani

The purpose of this paper is to find out the optimal level as well as the influence of end mill cutter geometrical and machining parameters while machining metal matrix…

Abstract

Purpose

The purpose of this paper is to find out the optimal level as well as the influence of end mill cutter geometrical and machining parameters while machining metal matrix composite. End milling is carried out on Al 356/SiC metal matrix composites (MMC) using high-speed steel (HSS) end mill cutter. The optimum level of input parameters such as helix angle, nose radius, rake angle, cutting speed, feed rate and depth of cut are calculated for minimum temperature rise.

Design/methodology/approach

L27 Taguchi orthogonal design, signal-to-noise (S/N) ratio, are applied for conducting experiments, and to find the optimal level of input parameters for minimum temperature rise, respectively. Analysis of variance (ANOVA) is used to analyze the significance of input parameters on temperature rise.

Findings

It is found that the optimal combination of helix angle 400, nose radius 0.8 mm, rake angle 80, cutting speed 30 m/min, feed rate 0.04 mm/rev and depth of cut 0.5 mm have generated minimum temperature rise. From ANOVA analysis, it is found that rake angle influence is more on output performance followed by cutting speed and nose radius compared with other machining and geometrical parameters.

Originality/value

The influence of geometrical parameters such as helix angle, nose radius and rake angle of end mill cutter on temperature rise while machining MMC has not been explored previously.

Details

World Journal of Engineering, vol. 17 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 4 July 2008

J.M. Longbottom and F. Dailami

This paper aims to examine the use of a commercial pyrometer to measure the surface temperature of workpieces as machining takes place. The pyrometer readings are to be…

Abstract

Purpose

This paper aims to examine the use of a commercial pyrometer to measure the surface temperature of workpieces as machining takes place. The pyrometer readings are to be compared with model predictions.

Design/methodology/approach

The pyrometer was mounted on an industrial milling machine and the temperature of the workpiece was measured behind the cutting tool as it traversed the workpiece. A mathematical spreadsheet model was used to predict the temperatures at the point measured by the pyrometer and at the point where cutting took place.

Findings

It was found by selecting the “partition ratio” of the power being transmitted to the workpiece that agreement could be found between measured and predicted results.

Research limitations/implications

The work was mainly carried out on aluminium samples, which exhibited low cutting temperatures.

Originality/value

The paper describes a method of finding the partition ratio of heat going into the workpiece.

Details

Aircraft Engineering and Aerospace Technology, vol. 80 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 April 2005

J.M. Longbottom and J.D. Lanham

This paper gives the background to the measurement of metal cutting temperatures and a review of the practicality of the various methods of measuring cutting temperature

11760

Abstract

Purpose

This paper gives the background to the measurement of metal cutting temperatures and a review of the practicality of the various methods of measuring cutting temperature while machining metals.

Design/methodology/approach

The review was compiled after a literature search, visits to other research establishments and discussions with other researchers in the machining/temperature measurement field.

Findings

Information about several methods of measuring cutting temperature during a machining process is given along with the limitations of the use of each method.

Practical implications

All the temperature measurement methods discussed have their limitations and these are described for each method listed.

Originality/value

The paper provides a review of all the cutting temperature measurement methods discovered in recent work. This will be a reference document of interest to others working in this field.

Details

Aircraft Engineering and Aerospace Technology, vol. 77 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 14 December 2020

Lawrance G., P. Sam Paul and Varadarajan A.S.

In the internal turning process, tool life and work piece quality are greatly influenced by the generation of heat in the cutting zone. During machining, cutting fluids…

Abstract

Purpose

In the internal turning process, tool life and work piece quality are greatly influenced by the generation of heat in the cutting zone. During machining, cutting fluids are applied at the cutting zones to reduce heat generation and enhance tribological properties. However, in the boring process, cutting fluids cannot be applied at cutting zone properly, and wastage of cutting fluid is a threat to the ecology and personnel health. Hence, application of semisolid lubricant in the boring process is considered as an innovative technique for temperature reduction in cutting zone because of its eco-friendly system, which also has a higher ability of biodegradability. This paper aims to study the influence of semisolid lubricants comprising of grease,graphite, aluminium oxide in different composition applied at a tool–chip,tool–work interface using a semisolid lubricant applicator applied with varying pressure.

Design/methodology/approach

In the present study, the cutting performance during boring of AISI4340 steel is enhanced through the application of semisolid lubricant with different composition of grease, graphite and aluminium oxide applied at tool-work and tool-chip interface with varying pressure using semisolid lubricant applicator.

Findings

The results show that use of semisolid lubricant like grease, graphite and nano aluminium oxide at tool-chip interface with maximum pressure reduces cutting temperature, tool vibration, cutting force and surface roughness.

Originality/value

Reduce cutting temperature, tool vibration, cutting force and surface roughness.

Details

World Journal of Engineering, vol. 18 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 9 April 2018

Ireneusz Zagórski and Jozef Kuczmaszewski

This paper presents the results of mean unit weight of chips and their time to ignition measured on a test stand specially designed for this purpose. In addition, the…

Abstract

Purpose

This paper presents the results of mean unit weight of chips and their time to ignition measured on a test stand specially designed for this purpose. In addition, the temperature of chips in the cutting area and the morphology of chips produced in HSM milling (as a temperature indicator in the cutting area) are investigated. Also, different fractions of chips produced in the dry milling of Mg alloys AZ31 and AZ91HP by a PCD end mill are examined. Finally, the paper presents conclusions and recommendations with regard to safety and efficiency of dry milling processes for the aforementioned magnesium alloys.

Design/methodology/approach

Milling can be used as a finishing operation, particularly when using PCD end mills. The application of this mill type isparticularly important when producing different machine and device components, especially in the aircraft industry. What can occur in dry machining operations is self-ignition. It is therefore justified to investigate chip temperature in the cutting zone, to classify produced chip fractions and to determine their mass. Safe ranges of technological parameters can be additionally determined based on metallographic analysis of chip edge partial-melting.

Findings

The experimental results helped determine the effect of technological parameters of milling on chip temperature in the cutting zone, chip mass and fragmentation and chip morphology images.

Practical implications

The results reported in this work are innovative in both cognitive and practical aspect. The authors are convinced that this work can contribute to overcoming the mistrust of industrial practitioners toward dry milling of Mg alloys, and also with respect to the application of relatively higher cutting speeds in dry milling of these alloys than it is common practice in industry today. The study investigates the problem of safety in dry milling of Mg alloys. The study was motivated by the milling process itself and the formation of broken chip, which causes a significant change in the character of heat transfer.

Originality/value

The paper presents a method for multi-criteria safety assessment in dry milling operations. Safe and effective parameter ranges are defined with respect to chip temperature in the cutting zone, fraction number and chip mass.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 October 2005

Rongdi Han, Junyan Liu and Yongfeng Sun

Nowadays, green cutting has become the focus because of its ecological problem and the necessary environment protection, so that the research on experimentation of green…

Abstract

Purpose

Nowadays, green cutting has become the focus because of its ecological problem and the necessary environment protection, so that the research on experimentation of green cutting with water vapor as coolant and lubricant is studied because water vapor has many benefits of cheapness, no pollution, no harm and no recycling and handling.

Design/methodology/approach

The vapor generator and the vapor feed system are manufactured, the distribution of temperature and velocity of vapor jet flow are simulated by MATLAB program, and under the conditions of compress air, oil water emulsion, water vapor as coolant and lubricant and dry cutting, respectively, the turning experimentation of comparison which the tool is YT15, and the working material is steel 45.

Findings

Water vapor, as coolant and lubricant, the cutting force is reduced, respectively about 30‐40, 20‐30 and 10‐15 percent by comparing to dry cutting, compressed air and oil water emulsion. The cutting temperature is, respectively about 30, 40 and 50 percent with the other conditions of dry cutting, compressed air and oil water emulsion. The friction coefficient and the chip deformation coefficient are correspondingly decreased and the surface roughness value has been diminished too. Through analysis of the experimental results, water vapor as coolant and lubricant possesses better lubricating action because of the excellent penetration performance and the low lubrication layer shearing strength of water vapor.

Originality/value

Water vapor as coolant and lubricant provides a novel method for realizing no contamination green cutting.

Details

Industrial Lubrication and Tribology, vol. 57 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 7 October 2021

Amrita Maddamasetty, Kamesh Bodduru, Siva Bevara, Rukmini Srikant Revuru and Sanjay Kumar

Inconel 718 is difficult to machine due to its high toughness and study hardenability. Though the use of cutting fluids alleviates the problem, it is not sustainable. So…

Abstract

Purpose

Inconel 718 is difficult to machine due to its high toughness and study hardenability. Though the use of cutting fluids alleviates the problem, it is not sustainable. So, supply of a small quantity of specialized coolant to the machining zone or use of a solid lubricant is a possible solution. The purpose of the present work is to improve machinability of Inconel718 using graphene nanoplatelets.

Design/methodology/approach

In the present study, graphene is used in the machining of Inconel 718 alloy. Graphene is applied in the following two forms: as a solid lubricant and as an inclusion in cutting fluid. Graphene-based self-lubricating tool and graphene added nanofluids are prepared and applied to turning of Inconel 718 at varying cutting velocities. Performances are compared by measuring cutting forces, cutting temperature, tool wear and surface roughness.

Findings

Graphene, in both forms, showed superior performance compared to dry machining. In total, 0.3 Wt.% graphene added nanofluids showed the lowest cutting tool temperature and flank wear with 44.95% and 83.37% decrease, respectively, compared to dry machining and lowest surface roughness, 0.424 times compared to dry machining at 87 m/min.

Originality/value

Graphene could improve the machinability of Inconel 718 when used in tools as a solid lubricant and also when used as a dispersant in cutting fluid. Graphene used as a dispersant in cutting fluid is found to be more effective.

Details

World Journal of Engineering, vol. 19 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 4 March 2014

T.S. Lee, C.F. How, Y.J. Lin and T.O. Ting

The purpose of this paper is to investigate and contribute to a better understanding of cutting process characteristics using the proposed RBD Palm Olein-based organic…

Abstract

Purpose

The purpose of this paper is to investigate and contribute to a better understanding of cutting process characteristics using the proposed RBD Palm Olein-based organic mixed coolant.

Design/methodology/approach

In this research, refined, bleached and deodorized (RBD) Palm Olein is selected as the base oil for organic coolant and mixed coolant (base oil mixed with chemicals) to compare with the cutting performance of industrial water-soluble chemical (inorganic) coolant. Using coated carbide tool, JIS SS400 Mild Steel was tested in milling process. At fixed spindle speed, the relations between feed rate and depth of cut (DOC) on cutting temperature and surface roughness were investigated. Also, the dynamic viscosity, specific heat capacity and pH level for each coolant are taken into consideration.

Findings

As predicted, cutting fluid with lower viscosity removes more heat. The cutting temperature increased with increasing feed rate and DOC. However, surface roughness increased with increasing feed rate but decreased with increasing DOC. From the data gathered, the proposed RBD Palm Olein-based organic mixed coolant showed better heat removal properties than organic coolant and it produced a far better machined surface than inorganic coolant.

Originality/value

Overall, the proposed organic mixed coolant has shown great potential to be a good cutting fluid when balance between cooling properties and lubricity, and consistent quality of cutting fluids are sought to produce environmental friendly quality workpiece.

Details

Industrial Lubrication and Tribology, vol. 66 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

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