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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of Manufacturing Technology Engineers
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Journal DOI :
The Korean Society of Manufacturing Technology Engineers
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Volume & Issues
Volume 21, Issue 6 - Dec 2012
Volume 21, Issue 5 - Oct 2012
Volume 21, Issue 4 - Aug 2012
Volume 21, Issue 3 - Jun 2012
Volume 21, Issue 2 - Apr 2012
Volume 21, Issue 1 - Feb 2012
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Mechatronic Analysis for Feeding a Structure of a Machine Tool Using Multi-body Dynamics
Choi, Jin-Woo ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 691~696
DOI : 10.7735/ksmte.2012.21.5.691
In this study, a rigid multi-body dynamic model has been developed for mechatronic analysis to evaluate dynamic behavior of a machine tool. The development environment was the commercialized analysis tool, ADAMS, for rigid multi-body dynamic analysis. A simplified servo control logic was implemented in the tool using its functions in order to negate any external tool of control definition. The advantage of the internal implementation includes convenience of the analysis process by saving time and efforts. Application of this development to a machine tool helps to evaluate its dynamic behavior against feeding its component, to calculate the motor torque, and to optimize parameters of the control logic.
Modeling for a Coke Dry Quenching Process Using a Theory of a Porous Material
Kim, Joo-Han ; Lee, Yong-Ju ; Kim, Ki-Seok ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 697~701
DOI : 10.7735/ksmte.2012.21.5.697
Numerical modeling for a coke dry quenching process was developed and evaluated. The cokes had similar characteristics to a porous material, therefore, its quenching analysis was simplified as a cooling process of porous blocks. A uniform inlet temperature and constant properties of materials in the oven were also assumed. With given operating conditions, temperature profiles in the cokes were calculated and compared to the actual values. The calculated temperature gradient was high at the upper part of the coke flow and the cooling rate decreased as cokes came down to the exit port. The exit port temperature of cokes was similar to the measured value, however, temperature-dependent material properties and operating conditions must be considered to predict the temperature precisely. The calculated results could be applied to design a coke oven to produce high quality cokes.
Linear Drive Systems using Roller Gear Mechanism
Kim, Chang-Hyun ; Nam, Hyoung-Chul ; Kwon, Soon-Man ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 702~707
DOI : 10.7735/ksmte.2012.21.5.702
This paper considers two linear drive systems using roller gear mechanism(RGM), one is the RRP(roller rack pinion) system that consists of a roller rack and a cam pinion, the other is the CRP(cam rack pinion) system that consists of a cam rack and a roller pinion. Through the comparison of contact forces and load-stress factors between two linear drive systems, it reveals that the RRP system is superior to the CRP system in the aspect of the bending strength, while the CRP system has higher contact fatigue resistance than that of the RRP system.
Indented Surface Configuration and its Volume Calculation
Yang, Jae-Yong ; Yoon, Moon-Chul ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 708~713
DOI : 10.7735/ksmte.2012.21.5.708
The indented geometry for rockwell hardness indenter has been configured by using Confocal Laser Scanning Microscopy (CLSM). For this purpose, the CLSM can be well suited to construct the three-dimensional indented volume from the indented surface by rockwell hardness tester. Furthermore, the height data of HEI(height encoded image) by CLSM must be acquired at first and converted to indented surface later. And the indented surface patterns enable us to predict the indenter shape and volume. This volume can be used to study the rockwell hardness model as a volume parameter. As a result, the technique performed in this study by combining the CLSM with compensation technique is an excellent one to obtain the geometries of indented surfaces over a wide range of surface resolution in a micro scale. And it can be used for micro volume calculation.
Micro Polishing Force Control of the Polishing Machine with the Airbag Tool
Lee, Ho-Cheol ; Lee, Chang-Eun ; Je, Tae-Jin ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 714~719
DOI : 10.7735/ksmte.2012.21.5.714
In this paper, the polishing force monitoring and the control method were implemented for the polishing machine with the airbag tool. Airbag tool has been known to be adaptable to the curvature variation such as the aspherical and the free-form surface. However, it was necessary to control the tool movement of vertical axis also because of the table rotational wobble and vibration. To solve it by the polishing force control, we installed another stepping motor to the z-axis. And the polishing force was measured with the load cell and controlled by the PID Labview controller. A few hundreds gram of the polishing force were well controlled under 0.8 second of the response time and 5% variation. An experiment was done to clean the edge burrs of the micro channel structure of width
using the polishing force control.
Effectiveness of the Electrochemical Sensor for the Free Chlorine Measurement
Kim, Hong-Won ; Chung, Nam-Yong ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 720~725
DOI : 10.7735/ksmte.2012.21.5.720
Sodium hypochlorite is used worldwide as a water disinfectant and in bleaching agent. Sodium hypochlorite applied to water initially undergoes hydrolysis to form free chlorine consisting of hypochlorous acid(HOCl) and hypochlorite ion(
). For free chlorine determination, an electrochemical method is simple due to the electroactivity of free chlorine; it measures current and is free of most reagents. Amperometric free chlorine sensor has been developed with gold (Au)-based electrode. The 3-electrode free chlorine sensor whose working and counter electrodes were Pt exhibited excellent response to HClO at +400mV vs. Ag/AgCl/sat. KCl. In addition, the use of a pH error correction algorithm provided a reliable measurement of residual free chlorine in water sample without any pretreatment in the normal pH range(pH 6~8) of municipal water supply. The free chlorine sensor installed in on-line monitoring system could be used to continually monitor the level of residual free chlorine in real samples.
Analysis of Error Rate in the Variations of Shearing Amount in Measuring the Internal Defect using a Shearography
Hong, Kyung-Min ; Kang, Young-June ; Choi, In-Young ; Ahn, Yong-Jin ; Yoon, Suk-Bum ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 726~732
DOI : 10.7735/ksmte.2012.21.5.726
Pipe and Pressure Vessels that is used in power plant and chemical industry have many Internal Defects that is corrosion caused by the flow of fluid. These Internal Defects that have possibility of explosion are very dangerous because it can not see from the outside. This days many companys using NDT method to find an Internal Defect. Most of the NDT methods have limitations that are constraint of shape and materials. But Sheargoraphy have many advantages compared conventional NDT method. It has very fast measuring speed, non-destructive and non contacting measurement. As well as it hasn't constraint of shape and materials. As a paper on the analysis of measurement of error, the important factors were the Shearing Amount and pressure, and discovered measurement of the Internal Defect of the object by using shearography. The optimal Shearing Amount and pressure was discovered and utilized.
Evaluation on Structural Stability According to Steering Wheel Type
Han, Moon-Sik ; Cho, Jae-Ung ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 733~740
DOI : 10.7735/ksmte.2012.21.5.733
This paper studies with structural and vibration analysis to evaluate the structural safety according to the types of steering wheels. This study models are two, three and four spoke types. As the number of spokes increases, the maximum equivalent stress becomes smaller but the maximum total deformation becomes a little higher. The natural frequency at three models are shown from 180 to 230Hz as the maximum deformation. The frequency responses as maximum amplitude displacement are happened at 200Hz, 500Hz and 500Hz respectively. In this study, the steering wheel with three spoke type is shown to become suitable at durability and production.
A Study on the Load Carrying Capacity and Equivalence Friction Coefficient of a Textured Plane Bearing with Semi-spherical Dimples and Semi-ellipsoidal Dimples
Lee, Soo-Young ; Kim, Pil-Kee ; Seok, Jong-Hyuk ; Seok, Jong-Won ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 741~746
DOI : 10.7735/ksmte.2012.21.5.741
The increase of energetic efficiency in plane bearing is getting more important in the transfer mechanism of semi-conductor and display panel manufacturing processes. To accomplish this objective, the technique of surface texturing on bearing surface has recently emerged as one of the most effective candidates. In this study, the effects of various pattern parameters on two bearing performance indices(load carrying capacity and effective friction coefficient) are investigated through a semi-analytic method, i.e., the 2-dimensional Reynolds equation incorporated into the finite difference scheme. Here, cavitation effect is also taken into account by employing an appropriate numerical scheme. In this study, the patterns in the textured surface are composed of a series of semi-spheres or semi-ellipsoids in shape. The effects of their size and number density on the performance indices are examined through the performance of various numerical experiments. Also, the effects of the anisotropy of the semi-ellipsoidal pattern on the bearing's lubrication characteristics are investigated and discussed.
Stress Analysis on a Structure of Solar Tracker Subjected to Wind Load
Kim, Yong-Woo ; Kim, Won-Bong ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 747~754
DOI : 10.7735/ksmte.2012.21.5.747
A solar power generator is usually installed outdoors and it is exposed to extreme environments such as snow weight and wind loading. The solar tracker structure should be designed to have sufficient stiffness and strength against such loads. In this paper, simulations are performed by varying the parameters such as wind directions, wind speeds and the pose of the solar panel to evaluate the effects of extreme wind on solar tracker. As the effects of wind load, maximum displacement and maximum equivalent stress in the solar tracker are calculated. Finite element stress analysis is carried out by using the pressure distribution that is obtained by prior wind load analysis due to the flow around the solar tracker. The stress analysis of solar tracker to check and/or improve structural robustness provides some useful instructions for structural design or revision of solar tracker.
Analysis of the Effects of Cutting Force and Surface Roughness in the Cutting Conditions of Plasma Source Ion Implantation Tools
Kang, Seong-Ki ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 755~760
DOI : 10.7735/ksmte.2012.21.5.755
In this study, three dimensional cutting force components and surface roughness appeared in high speed cutting by using tungsten carbide endmill tools implanted ion or not found mutual relations through several analysis of statistical dispersion. It is showed that cutting force(Fx) is affect with spindle speed and feed rate, cutting force(Fy) is affect with spindle speed and ion implantation time and cutting force(Fz) is affect with feed rate in interaction through the statistical method of ANOVA of cutting force and surface roughness, it is analyzed that it is affected of spindle speed and feed rate in surface roughness.
Investigation of Polishing Characteristics of Fused Silica Glass Using MR Fluid Jet Polishing
Lee, Jung-Won ; Cho, Yong-Kyu ; Cho, Myeong-Woo ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 761~766
DOI : 10.7735/ksmte.2012.21.5.761
Abrasive fluid jet polishing processes have been used for the polishing of optical surfaces with complex shapes. However, unstable and unpredictable polishing spots can be generated due to the fundamental property of an abrasive fluid jet that it begins to lose its coherence as the jet exits a nozzle. To solve such problems, MR fluid jet polishing has been suggested using a mixture of abrasives and MR fluid whose flow properties can be readily changed according to imposed magnetic field intensity. The MR fluid jet can be stabilized by imposed magnetic fields, thus it can remain collimated and coherent before it impinges upon the workpiece surface. In this study, MR fluid jet polishing characteristics of fused silica glass were investigated according to injection time and magnetic field intensity variations. Material removal rates and 3D profiles of the generated polishing spots were investigated. From the results, it can be confirmed that the developed MR fluid polishing system can be applied for stable and predictable precise polishing of optical parts.
Development of an Injection Nozzle and an Electromagnet Module for a MR Fluid Jet Polishing System
Lee, Jung-Won ; Cho, Yong-Kyu ; Ha, Seok-Jae ; Shin, Bong-Cheol ; Cho, Myeong-Woo ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 767~772
DOI : 10.7735/ksmte.2012.21.5.767
Generally, abrasive fluid jet polishing system has been used for polishing of complex shape or freeform surface which has steep local slopes. In the system, abrasive fluid jet is injected through a nozzle at high pressure; however, it is inevitable to lose its coherence as the jet exits a nozzle. This problem causes incorrect polishing results because of unstable and unpredictable workpiece material removal at the impact zone. In order to solve this problem, MR fluid jet polishing method has been developed using a mixture of abrasive and MR fluid which can maintain highly collimated and coherent jet by applied magnetic field. Thus, in this study, an injection nozzle and an electromagnetic module, most important parts in the MR polishing system, were designed and verified by magnetic field and flow analysis. As the results of experiments, it can be confirmed that stable fluid jets for polishing were generated since smooth W-shapes and uniform spot size were observed regardless of standoff distance changes.
A Study on Water Droplet Lens Effect of UV Laser Micromachining Process
Shin, Bo-Sung ; Lee, Jung-Han ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 773~777
DOI : 10.7735/ksmte.2012.21.5.773
Recently UV laser micromachining processes is widely introduced to meet the needs of advanced components of IT, BT and ET industries. Due to the characteristics of non-contact and high-speed laser processing, UV laser micromachining is applied to manufacture very thin substrate such as polymer, metals and composite. These minimum line width obtained by UV laser micromachining is generally determined from laser wavelength, optical lens and its numerical aperture. In this paper we will show the lens effect of water droplet on the surface of workpiece to reduce the line width when UV laser light is irradiated and focused through the water droplet. Because of the refraction effect generated by the semi-spherical or spherical shape of water droplet, we can find smaller line width. And water droplet could not only protect thermal deformation, but also carry away burr around micro dent. Firstly fundamental theory of minimum line width was derived from relationship between the geometry of water droplet and laser light trace, and then experimental and simulation results will be finally compared to verify the effectiveness of water droplet lens effect of UV laser micromachining process.
A Study on the Characteristics of the Clutch Automation Mechanism of Hybrid Vehicles
Lim, Won-Sik ; Park, Sung-Cheon ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 778~783
DOI : 10.7735/ksmte.2012.21.5.778
Due to the increase of oil price, the needs of the reduction of the fuel cost is rising. Therefore, necessity of hybrid vehicle that runs with engine and the electric motor is on the rise. In order to improve the performance of hybrid vehicle, many researches is carried out. Hybrid vehicles have been developed with the various layout such as serial type, parallel type, power split type, and multi-mode type. The multi-mode hybrid vehicles are designed to show the efficient driving characteristics at low speed and high speed. But the multi-mode system have the problem such as frequent clutch engagement. Frequent clutch engagement causes the shock of vehicles, and the shock inhibits the ride comfort. In this study, automation mechanism of clutch operation is proposed to mitigate the shock at engaging clutch. For this purpose, the dynamic characteristics of motor control is numerically analyzed by using Matlab/Simulink.
Prediction of Crack Initiation and Design of 40kHz Blade Horn for Ultrasonic Cutting
Seo, Jeong-Seok ; Lee, Yoon-Jung ; Beak, Si-Young ; Park, Dong-Sam ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 784~789
DOI : 10.7735/ksmte.2012.21.5.784
Ultrasonic Cutting which uses a tuned blade resonant in a longitudinal mode, has been used to cut a range of materials from confectionery, baked products and frozen foods, to wood, bone, foams and composites. The Blade design typically uses finite element analysis, and it could be predicted vibration mode, gain and amplitude uniformity of the blade tip at resonant frequency. In this paper, FEA used to predict the vibration characteristic of the blade, and then the results were verified by analysis system of resonant frequency using the processed blade. The crack of the blade which is predicted from FEA was compared with the crack occurred by cutting experiment of rubber materials using the processed blade.
An Experimental Study on Cutting Process using High Pressure Injection Holder
Chung, Sang-Wan ; Jeong, In-Guk ; Yi, Chung-Seob ; Song, Chul-Ki ; Suh, Jeong-Se ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 790~796
DOI : 10.7735/ksmte.2012.21.5.790
Chip curling occurred during cutting process for difficult-to-cut material detracts product qualities and productivity. Among of method preventing the phenomenon, high pressure injecting cutting oil is an alterative. In this study, the optimal nozzle was designed by CFD method and it was conducted to analyse on the effect of high pressure injection on chip shape generated during cutting process and wear of insert by experimental method. As the result, it could be confirmed that high pressure injection is favorable for preventing chip curling and insert from wearing.
A Study of Optimal Design for Mg Armrest Frame by using Response Surface Method
Kim, Eun-Sung ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 797~804
DOI : 10.7735/ksmte.2012.21.5.797
Magnesium has a long tradition of use as a lightweight material in the field of automotive industry. This paper presents the design optimization process of Mg armrest frame to minimize its weight by replacing the steel frame. formerly, the analysis of steel armrest frame was peformed to determine the design specifications for Mg armrest frame. The initial design of Mg armrest frame was carried out by topological optimization technique. After six types of design variables and four types of response variables were defined, DOE(Design of Experiment) and RSM (Response Surface Method) were applied in order to measure sensitivity of design variables and realize optimization through regression model. After design optimization, the weight of the optimized Mg armrest frame was reduced by about 3% compared to the initial design of the Mg frame and was decreased by 41.7% in comparison with that of the steel frame. Some prototypical armrest frames were also made by die casting process and tested. The results were satisfying for its design specifications.
Development of a Fan Simulator Using Supercomputer
Kim, Myung-Il ; Kim, Seung-Hae ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 805~813
DOI : 10.7735/ksmte.2012.21.5.805
A fan is the most common air flow machinery and is being used in various different industries such as for heavy machinery, home appliances and automobile. An axial fan has blades that force air to move parallel to the shaft about which the blades rotate. This type of fan is used in a wide variety of applications, ranging from small cooling fans for electronics to the giant fans used in wind tunnels. An axial fan generating large air volume used to cool equipments, but is less efficient. A sirocco fan is a efficient device for moving air by centrifugal force and can generate high pressure. Fans that affect the performance and noise of a product are important components. It is also a time and budget consuming equipment to develop a fan through physical experiments. In order to overcome this problem, we have designed and developed a fan simulator for axial and sirocco fan's fluid analysis using supercomputer. Performance and noise prediction based on datamining without numerical analyses is also developed for the conceptual design of a fan.
A Study on the Monitoring of Laser Welding for S45C Steel Sheets Using Nd:YAG Laser with Continuous Waves
Kim, Do-Hyoung ; Shin, Ho-Jun ; Yoo, Young-Tae ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 814~823
DOI : 10.7735/ksmte.2012.21.5.814
Fluctuation of light intensity from the keyhole becomes more significant in full penetration welding than partial penetration welding, since the plasma produced in the keyhole can escape from the rear side of the keyhole. The plasma optical radiation emitted during Nd:YAG laser welding of S45C steel samples has been detected with a Photodiode and analyzed under different process conditions. As the results, the BOP was performed for welding, behavior of plasma, spatter or plume was monitored to determine the reference signal. Then, random combination was made for comparison with the reference signal, which aimed at verifying reliability of the welding monitoring system that this study intended to develop.
A Study on Roundness Improvement of Heat-treated Large Diameter Aluminum Tube-turning with Collet Type Jig
Kim, Pyeong-Ho ; Lim, Hak-Jin ; Lee, Jung-Min ; Lee, Jong-Hwan ; Kim, Jung-Suk ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 824~829
DOI : 10.7735/ksmte.2012.21.5.824
The purpose of this study is to evaluate the proposed jig for turning process of large-scale aluminum tube of D500mm through Finite Element Analysis (FEA). Also, a machining evaluation is conducted with general heat-treated and cryogenic heat-treated tubes. Dimensions of the specimens are determined to be suitable for collet appearance. The characteristics of equivalent stress and strain according to the expansion of the collet are evaluated by FEA. The aluminum tubes which are heat-treated by T4/T6 condition and cryogenic condition are machined by using a large-scale lathe machine and the roundness of machined tube is evaluated by using a 3D measuring machine. Through the results of this study, effects of each heat treatment and residual stress on the roundness are established.
An Evaluation of the Fatigue Properties for External Panel Using Low Density SMC
Kim, Eun-Sung ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 830~835
DOI : 10.7735/ksmte.2012.21.5.830
A research for application of LDSMC(Low Density Sheet Molding Compound) composite is in progress for lightening the weight. This paper has performed fatigue test and simulation of external panel for Korean commercial vehicle. Before the fatigue test, static test was carried out. From the test, the structural safety was investigated using Goodman diagram. After the static test performance, the fatigue test was conducted at a range of load frequency 5Hz, a stress ratio(R) of 0.05 and an endurance limit of
to obtain the S-N curve. The S-N curve is applied to the fatigue analysis of the external panel assembly. The result of FEM analysis was in accord with the experimental result within 83% confidence. It showed that the process to set up the safety range of allowable error is required in process of the design and simulation verification.
The Research on Environmental-Friendly Manhole Repair and Construction Technology
Seo, Jeong-Hwan ; Yang, Hae-Jeong ; Kim, Kwang ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 836~841
DOI : 10.7735/ksmte.2012.21.5.836
The repair of road pavement and manhole has been resulted long construction times and traffic jams, environmental pollution from construction wastes, and budget waste due to excessive construction costs. In order to resolve such problems, we have developed the new construction method using C-ring, which can fix and raise the manhole securely. This technology is the method by driving in a wedge after inserting C-ring and expanding it in order to raise manhole to the regular height. This has been approved by the test reports of KOLAS(Korea Laboratory Accreditation Scheme), and was confirmed safety, durability and reliabilty in result. In this paper we approved this technology was able to short working times to around 20% and construction costs to around 50% with compare other construction methods. Also, environmental pollution and civil complaints will be prevented because there will be no longer any noises, vibrations, dust, or construction wastes.
Machining Optimization of Al7075-T0 Turning Process Considering Surface Roughness and Cutting Forces
Jeong, Ji-Hoon ; Kim, Jeong-Suk ; Kim, Pyeong-Ho ; Koo, Joon-Young ; Im, Hak-Jin ; Lee, Jong-Hwan ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 842~847
DOI : 10.7735/ksmte.2012.21.5.842
The Response Surface Method(RSM) is used as optimal design technique of experimental conditions. In Al7075-T0 turning operation, the principle cutting force and the Center-line averaged roughness are measured to optimize machining process. In variation of feed, depth of cut and cutting speed, three cutting parameters are evaluated. The optimal cutting conditions of Al7075-T0 turning are suggested by RSM. As a main result, feed is the dominant cutting parameter in this turning process considering surface roughness and cutting force.
Evaluation Tool Life and Cutting Characteristics of Carbide Hob TiAlN Coating Surface Polishing Using Aero Lap Polishing Technology and Multi-con
Cheon, Jong-Pil ; Pyoun, Young-Sik ;
Journal of Manufacturing Technology Engineers, volume 21, issue 5, 2012, Pages 848~854
DOI : 10.7735/ksmte.2012.21.5.848
SCM420 steel cutting gear to improve the durability is quenched. When quenching, increases surface hardness, a change of the physical properties and machinability or fall. This study, using a solid carbide hobs skiving hobbing gear cutting finishing. And cutting tool solid carbide TiAlN coating hove when TiAlN coating on the surface of multi-con polishing hob conducted aero lap nano polishing for each cutting. Experimental results conducted aero lap nano coating on the surface polishing tool machinability was excellent. And aero lap nano polishing tool results were reduced 2.5 times the tool wear compared to TiAlN coated tools. Excellent results were 1.42 times longer tool life.