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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 22, Issue 6 - Dec 2013
Volume 22, Issue 5 - Oct 2013
Volume 22, Issue 4 - Aug 2013
Volume 22, Issue 3 - Jun 2013
Volume 22, Issue 3_1spc - Jun 2013
Volume 22, Issue 2 - Apr 2013
Volume 22, Issue 1 - Feb 2013
Selecting the target year
A Study on the Meter-Out and Meter-In Speed Control Characteristics in Pneumatic Cushion Cylinders
Kim, Do-Tae ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 1~7
DOI : 10.7735/ksmte.2013.22.1.1
Pneumatic cylinders are widely used to actuators in automatic equipments because they are relatively inexpensive, simple to install and maintain, offer robust design and operation, are available in a wide range of standard sizes and design alternatives. This paper presents a comparative study among the dynamic characteristics of meter-out and meter-in speed control of pneumatic cushion cylinders with a relief valve type cushion mechanism. Because of the nonlinear differential equations and a requirement for simultaneous iterative solution in a mathematical model of a double acting pneumatic cushion cylinder, a computer simulation is carried out to investigate pressure, temperature, mass flow rate in cushion chamber and displacement and velocity time histories of piston under various operating conditions. It is found that the piston velocity and pressure response in meter-in speed control are more oscillatory than with meter-out those when pneumatic cushion cylinders are driven at a high-speed. In meter-out speed control, the effective area of the flow control valve is larger than that of meter-in, and the supply pressure has to be much higher than the pressure required to move the load because it has also to overcome the back pressure in cushion chamber.
Stability Analysis of an Asymmetric Shaft with Internal Damping
Shin, Eung-Soo ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 8~14
DOI : 10.7735/ksmte.2013.22.1.8
This paper intends to provide the whirling characteristics of an asymmetric rotor-shaft system with a non-ideal DC motor. The equations of motion have been derived in terms of system parameters such as the internal/external damping, the asymmetry and the motor voltage. By imposing the conditions that the motor input power should be balanced by the dissipated power, steadystate whirling characteristics are obtained such as the whirling amplitude, the whirling frequency and the stability diagrams. Results show that the whirling stability is affected by the internal/external damping and the asymmetry as well as the motor voltage. Also, the whirling amplitude at the steadystate is increased and the motor speed is lowered as the internal damping becomes higher or the external damping is reduced. In addition, the asymmetry causes the variation of the whirling orbit, which becomes splitted into two distinct trajectories. Finally, non-ideal characteristics of the DC motor is found to reduce the whirling motion in case of steadystate whirling with high asymmetry and high internal damping.
Measurements of Flow Meniscus Movement in a Micro Capillary Tube
Lee, Sukjong ; Sung, Jaeyong ; Lee, Myeong Ho ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 15~21
DOI : 10.7735/ksmte.2013.22.1.15
In this paper, a high-speed imaging and an image processing technique have been applied to detect the position of a meniscus as a function of time in the micro capillary flows. Two fluids with low and high viscosities, ethylene glycol and glycerin, were dropped into the entrance well of a circular capillary tube. The filling times of the meniscus in both cases of ethylene glycol and glycerin were compared with the theoretical models - Washburn model and its modified model based on Newman's dynamic contact angle equation. To evaluate the model coefficients of Newman's dynamic contact angle, time-varying contact angles under the capillary flows were measured using an image processing technique. By considering the dynamic contact angle, the estimated filling time from the modified Washburn model agrees well with the experimental data. Especially, for the lower-viscosity fluid, the consideration of dynamic contact angle is more significant than for the higher-viscosity fluid.
A Study Evaluating Welding Quality in Pressure Vessel Using Mahalanobis Distance
Kim, Ill Soo ; Lee, Jong Pyo ; Lee, Ji Hye ; Jung, Sung Myoung ; Kim, Young Su ; Chand, Reenal Ritesh ; Park, Min Ho ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 22~28
DOI : 10.7735/ksmte.2013.22.1.22
Robotic GMA (Gas Metal Arc) welding process is one of widely acceptable metal joining process. The heat and mass inputs are coupled and transferred by the weld arc to the molten weld pool and by the molten metal that is being transferred to the weld pool. The amount and distribution of the input energy are basically controlled by the obvious and careful choices of welding process parameters in order to accomplish the optimal bead geometry and the desired quality of the weldment. To make effective use of automated and robotic GMA welding, it is imperative to predict online faults for bead geometry and welding quality with respect to welding parameters, applicable to all welding positions and covering a wide range of material thickness. MD (Mahalanobis Distance) technique was employed for investigating and modeling the GMA welding process and significance test techniques were applied for the interpretation of the experimental data. To successfully accomplish this objective, two sets of experiment were performed with different welding parameters; the welded samples from SM 490A steel flats. First, a set of weldments without any faults were generated in a number of repeated sessions in order to be used as references. The experimental results of current and voltage waveforms were used to predict the magnitude of bead geometry and welding quality, and to establish the relationships between weld process parameters and online welding faults. Statistical models developed from experimental results which can be used to quantify the welding quality with respect to process parameters in order to achieve the desired bead geometry based on weld quality criteria.
Effects of Bearing Internal Clearance on the Load Distribution and Load Sharing in the Pitch Reducer for Wind Turbines
Kim, Jeong-Kil ; Park, Young-Jun ; Lee, Geun-Ho ; Kim, Jae-Hoon ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 29~35
DOI : 10.7735/ksmte.2013.22.1.29
The pitch reducer consists of several planetary gearsets, and they should have good load distribution over gear tooth flank and load sharing among the planets to improve the durability. This work investigates how bearing internal clearances influence both the load distribution over the gear tooth flank and the planet load sharing. A whole system model is developed to analyze a pitch reducer. The model includes non-linear mesh stiffness of gears, non-linear stiffness of bearings. The results indicate that the face load factor and mesh load factor decrease, and the fatigue life of output shaft bearings increase as bearing internal clearances of output shaft decrease. Therefore, the internal clearance of output shaft bearing must be considered when designing the pitch reducer for wind turbines.
Durability Analysis by Shape of Brake Disk Structure
Han, Moonsik ; Cho, Jaeung ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 36~44
DOI : 10.7735/ksmte.2013.22.1.36
This study investigates life, damage and durability through the analyses of fatigue load and vibration on disk brake models of A, B and C. Maximum equivalent stress is happened at the inside of disk brake on these models. As there are A, B and C models by order of life, model A has the most stable strength on fatigue analysis, The deformations at 3 kinds of models become nearly same on natural frequency analysis. The maximum total deformation and equivalent stress is shown at 1617Hz by harmonic vibration analysis on these models. As there are A, B and C models by order of deformation and stress, model A becomes lowest and safest. This study result can be effectively utilized with the design of brake disk in order to improve durability and prevention against its fatigue damage and vibration.
Estimating Material Parameters of Rubber-liked Material Similar to Biomaterial
Kang, Taewon ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 45~49
DOI : 10.7735/ksmte.2013.22.1.45
It is important to have a well developed strain energy function in order to understand the mechanical behavior of biomaterial like the blood vessel of artery. However, since it is not possible to have a complete form of strain energy function of artery, theoretical framework describing the behaviour of Rubber-like material which is similar to blood vessel is applied to infer useful forms of strain energy function of biomaterial. Based on Chuong-Fung model and Mooney-Rivlin model, material parameters are estimated based on experimental data. From the results, it can be inferred that the estimated parameters can be used to explain the difference of mechanical characteristics between normal vessel and vessel with stent.
Theoretical Framework For Describing Strain Energy Function on Biomaterial
Kang, Taewon ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 50~55
DOI : 10.7735/ksmte.2013.22.1.50
In order to understand the biomaterial like the blood vessel of artery, there is a need to quantify the biomechanical behavior of the vessel. However, theoretical framework to describe and quantify the behaviour of blood vessel was not well established so far. For studying the biomechanical behavior of artery, Rubber-liked material which is similar to passive artery is selected since conventional theoretical interpretation is very limited to understand and predict the behavior of biomaterial. Rubber-like material is assumed to be very similar to artery and has properties of isotropy, homogeneity and is undergoing large deformation. Based on this assumption, stress developed on Rubber-like material is described by strain energy function and strain invariants which are required to understand the nonlinear elastic behavior of biomaterial. The descriptor which would be used for understanding the biomechanical behavior of artery is studied in this work.
Laser Cutting of Flexible Printed Circuit Board in Liquid
Kim, Teakgu ; Kim, Joohan ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 56~62
DOI : 10.7735/ksmte.2013.22.1.56
The laser cutting process which is flexible and rapid usually provides a better result in cutting of flexible printed circuit boards (FPCB). However, circuit-short by the re-deposition of debris from laser ablation or its heat affect zone (HAZ) on the cutting surfaces can be a problem. A laser cutting process of FPCB in the presence of liquid can minimize these negative effects. The temperature distribution of copper and polymer parts of FPCB was analyzed with numerical simulation and the experimental results were presented to evaluate this process. Generally, laser cutting under liquid has advantages of less re-deposition of carbides and less HAZ on the cutting edges. However, bubble generation and laser beam control through the liquid media should be considered carefully to obtain a successful result.
Structure Optimization FEA Code Development Under Frequency Constraints by Using Feasible Direction Optimization Method
Cho, Hee Keun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 63~69
DOI : 10.7735/ksmte.2013.22.1.63
In order to find the optimum design of structures that have characteristic natural frequency range, a numerical optimization method to solving eigenvalue problems is a widely used approach. However in the most cases, it is difficult to decide the accurate thickness and shape of structures that have allowable natural frequency in design constraints. Parallel analysis algorithm involving the feasible direction optimization method and Rayleigh-Ritz eigenvalue solving method is developed. The method is implemented by using finite element method. It calculates the optimal thickness and the thickness ratio of individual elements of the 2-D plane element through a parallel algorithm method which satisfy the design constraint of natural frequency. As a result this method of optimization for natural frequency by using finite element method can determine the optimal size or its ratio of geometrically complicated shape and large scale structure.
Structure Structural Durability Analysis on Bike Carrier Basket
Cho, Jaeung ; Han, Moonsik ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 70~76
DOI : 10.7735/ksmte.2013.22.1.70
This study investigates structural durability through the analyses of stress, fatigue life and vibration damage at bike carrier basket. As model 2 has less stress and deformation than model 1 on static structural analysis, model 2 becomes more durable than model 1. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. The amplitude deformations become highest at maximum response frequency of 2400Hz in cases of models 1 and 2. As the values of maximum equivalent stresses become within the allowable material stresses at two holes at the upper parts on models 1 and 2, these models become safe. The structural result of this study can be effectively utilized with the design of bike carrier basket by investigating prevention and durability against fatigue or vibration damage.
Measuring Methods for Two-dimensional Position Referring to the Target Pattern
Jung, Kwang Suk ; Lee, Sang Heon ; Park, Sung-Jun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 77~84
DOI : 10.7735/ksmte.2013.22.1.77
In this paper, we review two-dimensional measuring methods referring to target patterns. The patterns consist of two linearly-repeated patterns or is designed repeatedly in two-dimension. The repeated properties are reflectivity, refractivity, air-gapping distance, capacitance, magnetic reluctance, electrical resistance and sloping gradient, etc. However, the optical methods are generally used for high speed processing and density, and their encoding principles are treated here. In case of two-dimensional pattern, as there is not inherently error between single units encoding the pattern except for the metrology frame errors, the end-effector position of an object accompanying the pattern can be measured with respect of the global frame without via error. Therefore, it is regarded as a substitute for laser interferometer with severe environmental constraints and has been applied to the high-accurate planar actuator.
Wear Mechanism and Machinability of PCD Tool in Turning Tungsten Carbides
Heo, Sung Jung ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 85~91
DOI : 10.7735/ksmte.2013.22.1.85
The machinability of wear-resistible tungsten carbides and the tool wear behavior in machining of V30 and V50 tungsten carbides using PCD (Poly Crystalline Diamond) cutting tool was investigated to understand machining characteristics. This material is one of the difficult-to-cut materials in present, but their usage has been already broadened to every commercial applications such as mining tools, and impact resistant tools etc. Summary of the results are as follows. (1) Tool wear progression of PCD tools in turning of wear-resistible tungsten carbides were observed specially fast in primary cutting distance within 10m. (2) Three components of cutting resistance in this research were different in balance from the ordinary cutting such as that cutting of steel or cast iron. Those were expressed large value by order of thrust force, principal force, feed force. (3) If presume from viewpoint of high efficient cutting within this research, a proper cutting speed was 15m/min and a proper feed rate was 0.1mm/rev. In this case, it was found that the tool life of PCD tool was cutting distance until 230m approximately. (4) In cutting of wear-resistible tungsten carbides such as V30 and V50, it was recognized that the tool wear rate of V30 was very fast as compared with V50. (5) When the depth of cut was 0.1mm, there was no influence of the feed rate on the feed force. And the feed force tended to decrease as the cutting distance was long, because the tool was worn and the tool edge retreated. (6) It was observed that the tungsten carbides were adhered to the flank.
A Study of Board the Train Designed for Wheelchair Users on Welding Condition
Lee, Chul Ku ; Kim, Incheol ; Lee, Wooram ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 92~99
DOI : 10.7735/ksmte.2013.22.1.92
The ratio of mobility handicapped was 12,110,000 in late 2009 about 24.4% of total population. The number of handicapped population is increasing continuously due to traffic accidents and industrial disasters. Therefore, the purpose of this research is to suggest a design for passengers on wheelchairs to get into and off to raise handicapped or elderly people's right of mobility. The scope of this research is mobility handicapped especially wheelchair passengers who use vans, small buses, and trains. The ramp design of vans is module form. The ramp is moved with screw jack and guides are installed on each side to increase stability. Moreover, a bridge was installed for smooth getting in and off of the van. The ramp design for small bus is lowed by 200m in order not to have obstacle such as speed bump when getting in or off. In order to reduce vulnerable environment and administration, air slide cylinder was chosen. Lastly, for the ramp design of train, the principle of link was used that the simpler structure made the weight lighter and installation in the train became easier. If we look at the conjugation condition of heterogeneous materials to produce a ramp, proper welding condition for cold steel plate and stainless plate is 3kW output and 3-5m/min of welding speed using laser beam seems proper.
A Structural Design of Multilevel Decomposition and Mapping
Lee, Jeong Ick ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 100~106
DOI : 10.7735/ksmte.2013.22.1.100
This paper describes an integrated optimization design using multilevel decomposition technique on the base of the parametric distribution and independent axiom at the stages of lower level. Based on Pareto optimum solution, the detailed parameters at the lower level can be defined into the independent axiom. The suspension design is used as the simulation example.
Mechanical Design of Ring Laser Gyroscope Using Finite Element Method
Lee, Jeong Ick ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 107~111
DOI : 10.7735/ksmte.2013.22.1.107
The gyroscopes have been used as a suitable inertial instrument for the navigation guidance and attitude controls. The accuracy as very sensitive sensor is limited by the lock-in region (dead band) due to the frequency coupling between two counter-propagating waves at low rotation rates. This frequency coupling gives no phase difference, and an angular increment is not detected. This problem can be overcome by mechanically dithering the gyroscope. This paper presents the design method of mechanical dither by the theoretical considerations and the verification of the theoretical equations through FEM applications. As a result, comparing to the past result, the maximum prediction error of resonant frequency was within 3 percent and peak dither rate was within 5 percent. It was found that the theoretical equations can be feasible for the mechanical performance of dither.
Optimal Design of the Front Upright of Formula Race Car Using Taguchi's Orthogonal Array
Jang, Woon Geun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 112~118
DOI : 10.7735/ksmte.2013.22.1.112
Formula race car is generally recognized as a vehicle which is optimally designed for on-road race track with the regulations of race host bodies. Especially, the uprights of suspension system decisively have effects on the performance of cornering and stability of race car's driving performance, which are very important factors in the design of race car. This paper is a study of optimal upright design of F1800 grade formula race car which are normally used in professional race circuit in Korea. To design optimally the front upright of F1800 formula race car, Taguchi's orthogonal array, which is known for more useful method than full factorial design experimental method in cost and time, is used with CAE method such as FEM analysis. And the result of this paper shows that Taguchi's orthogonal array employed for this optimal design is very useful for designing the front upright of race car by minimizing its weight as well as keeping its safety factor as enough as designer wants in the view of quality, cost and delivery at the early design step.
Development of Biodiesel Production Equipment from Animal Fats and Consideration for Reaction Condition of Animal Biodiesel
Kim, Yong Hun ; Cho, Young Hak ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 119~124
DOI : 10.7735/ksmte.2013.22.1.119
In this paper, we analysed fatty acid methyl ester contents in the biodiesel which is produced from the newly developed biodiesel production equipment. The lard oil was used as the raw material through various experimental conditions. Thirty one experiments were conducted, which were based on the experimental conditions that designed by central composite design method. The effects of four independent variables, including reaction temperature, reaction time, oil to methanol molar ratio, and catalytic amount, were investigated at five levels using central composite design (CCD). Fatty acid methyl ester content was chosen dependent variable. Although the results of analysis of the surface with an irregular surface geometry showed that the biodiesel was partially impure after the reaction due to the natural characteristics of the lard oil as the raw material, we could confirm the relationship between them from the facts that the production amount of fatty acid methyl ester changes according to reaction temperature, reaction time, oil to methanol molar ratio, and catalytic amount.
Development of an Automatic Inspection System for PWM Shaft Using Machine Vision
Bae, Jin-Ho ; Kim, Sung-Gaun ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 125~130
DOI : 10.7735/ksmte.2013.22.1.125
In this paper, in order to overcome shortcomings of manual inspection for the automotive PWM Shaft, we developed an automated inline inspection system. The automated inline inspection system consists of the work feeder unit, conveying unit, outer diameter check unit, run-out and roundness check unit, machine vision, defective separation unit and status alarm unit. We used the machine vision system for automatic inspection process and designed the inline systems for automatic feeding and selecting process. Also the repeated operation test was performed in order to verify the precision and reliability of the proposed automated inline inspection system.
A Study on the Auto-moblie Gas Spring Structural Analysis Using of Bimetal
Park, Chul Woo ; Kim, Ho Yoon ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 131~137
DOI : 10.7735/ksmte.2013.22.1.131
Gas springs have been widely used in motor vehicles as well as in most areas of industry. Instead of coil springs, these gas springs are easily operated to extrusion process or compression process the doors because
gas with high pressure and oil are charged in tube. Gas spring sustain the constant elasticity change rate in the high reaction force and long stroke, and they have compact design, appearance and an excellent assembling ability to be mounted easily with any applicatory products. By means of these aspects, gas springs have been widely used in stead of coil springs in the over all industries. In this study, using acommonly used program, ANSYS, the basic research about the heat transfer and equivalent stress change of bimetal.
The structure Optimization Research of the Automation Welding Equipment of the Large L-type Using the Response Surface Method
Jang, Junho ; Jung, Wonjee ; Lee, Dongsun ; Jung, Jangsik ; Jung, Sung Ho ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 138~144
DOI : 10.7735/ksmte.2013.22.1.138
The automation technology for overlay welding is needed due to the occurrence of severe corrosion and abrasion on the surface of internal contact in different shape of fittings. In Korea, different shapes of fittings have been manufactured by using the imported equipment of overlay welding automation at some companies. Thus the research on the development of overlay welding automation system (in short, OWAS) for a large L-type tube is urgently needed. In this paper, the investigation is focused on the optimal design of a supporting base for the (currently developing) OWAS of large L-type tube. Specifically we assume that the base which supports the equipment during the process of overlay welding is loaded as self-weight in the direction of gravity through static analysis especially when it is rotated 180 degree on the OWAS. For optimal design of a supporting base for OWAS of large L-type tube, Solidworks(R) (for 3-dimensional modelling) and ANASYS Workbench(R) (for structural analysis) are incorporated so as to proceed an optimization routines based on Response Surface Method (RSM) and Design of Experiment (DOE). In more specific, DOE finds out major factors (or dimensions) of the supporting base by using MINITAB(R). Then the regression equations between design variables (the major factors of supporting base) and response variables (deformation, stress and safety factor for the supporting base), which will be resulted in by RSM, verify the major factors of DOE. In the next step, Central Composite Design (CCD) plans 20 simulations of ANASYS Workbench(R) and then figures out the optimal values of design variables which will be reflected on the manufacturing of supporting base. Finally welding experiment is conducted to figure out the influence of overlay welding quality in applying the optimized design values of supporting base to the actual OWAS.
Measurement Uncertainty Estimation of Injection Temperature in Injection Molding Machine
Jung, Hyun-Suk ; Yoo, Joong-Hak ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 145~149
DOI : 10.7735/ksmte.2013.22.1.145
The performance of injection molding machine's control system, such as reproducibility, repeatability, etc, is widely studied nowadays. Since screw stroke, injection cylinder body pressure and barrel temperature are the most important terms of injection unit, interval linearity and repeatability to each parameter are analyzed here. Barrel temperature is analyzed according to the repeatability of the thermocouple at
using a precise oven. The result temperature is within
Through the reliability evaluation of the most important terms of injection unit, the method of evaluating the linearity and repeatability is proposed and verified.
Development of Vehicle Sealing Inspection System Using Geometry Matching Method
Lee, Jung-Ho ; Park, Chan-Hee ; Seo, Young-Soo ; Lee, Hyung-Soo ; Kim, Han-Joo ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 150~155
DOI : 10.7735/ksmte.2013.22.1.150
This work present a new method of sealing inspection system for vehicle in which foam rubber materials are used for sealing the vehicle parts. This system is composed from a devices comprising non-contact and real-time scanning on visual inspection in machine parts. We have been investigated qualitative factors that influenced on sealing system of vehicle structure which flexibly attenuated vibration and plenty of foam rubber materials having elastic property. However, there are different factors which still depended on outdated technique (personnel subjective judgment) in the performance inspection of rubber parts, specially for cross section inspection. Through a newly developed inspection system which recently applied for the production line, we successfully achieved more effective results of matching rate by about 80 % in the sealing performance inspection with 0.7% to 1.4% in the repeated errors. These are resulted from non-contacted response by CCD camera and vision program using geometry matching method. We expect that this system may be widely applied in the strict inspection parts of more diverse cross-section in future.
Development of Cable Lug Joint Using Electromagnetic Force
Shim, Ji-Yeon ; Kang, Bong-Yong ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 156~161
DOI : 10.7735/ksmte.2013.22.1.156
Recently, there has been a trend in the manufacturing process to focus on the durability of cable lug joint, especially in welding process due to the poor cable lug joint causes many troubles on products and workers during manufacturing process. Therefore development of high quality cable lug joint is important for successful manufacturing process and safety of worker. The Magnetic Pulse Forming(MPF) is one of efficient way to developed a high quality cable lug joint. In MPF, a high strain rate forming process, utilizes a high velocity oblique collision on the workpiece to be formed in required shape. The objective of this paper is to develop of high quality cable lug joint using electromagnetic force. To successfully accomplish this goal, section and electrical contact temperature of developed cable lug joint has been compared with various cable lug joint. Electrical contact temperature of developed cable lug joint by electromagnetic force is lower than manufactured cable lug joint by pressurer and hydraulic pressurer.
An Experiment of Machineable Width and Thickness of Airframe Thin Plate Structure
Shin, Yong-Bo ; Kim, Su-Jin ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 162~167
DOI : 10.7735/ksmte.2013.22.1.162
The most important factor in an aircraft manufacturing is stability and weight reduction. Most of aircraft components are designed with thin plate type to satisfy weight reduction needs. The thin plate is difficult to be machined because it is apt to be vibrated by dynamic force generated in milling process. The most critical factor in machining of aluminum thin plate is width and thickness between stiffeners. So we tested many cases to find out the machinable minimum thickness at different width between stiffeners. And with the data obtained from many tests, this papers suggested the standard width thickness relation that is machinable without vacuum fixture. Machinist will be able to reduce the cost of aircraft thin plate parts by reducing the number of vacuum fixture used by the help of this standard.
Warpage Simulation by the CTE mismatch in Blanket Structured Wafer Level 3D packaging
Kim, Seong Keol ; Jang, Chong-Min ; Hwang, Jung-Min ; Park, Man-Chul ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 168~172
DOI : 10.7735/ksmte.2013.22.1.168
In 3D wafer-stacking technology, one of the major issues is wafer warpage. Especially, The important reason of warpage has been known due to CTE(Coefficient of Thermal Expansion) mismatch between materials. It was too hard to choose how to make the FE model for blanket structured wafer level 3D packaging, because the thickness of each layer in wafer level 3D packaging was too small (micro meter or nano meter scale) comparing with diameter of wafer (6 or 8 inches). In this study, the FE model using the shell element was selected and simulated by the ANSYS WorkBench to investigate effects of the CTE on the warpage. To verify the FE model, it was compared by experimental results.
The Development of Aluminum Alloy Piston for Two-Stroke Cycle Engine by Powder Forging
Park, Chul-Woo ;
Journal of Manufacturing Technology Engineers, volume 22, issue 1, 2013, Pages 173~177
DOI : 10.7735/ksmte.2013.22.1.173
The purpose of this paper is to investigate the influences on mechanical properties of two-stroke cycle motor pistons manufactured by casting, conventional forging and powder forging, through the comparison of characteristics, merits and disadvantages of each forming technology. For each forming technology, the optimal process parameters were determined through the experiments for several conditions, and microstructure, hardness, tensile strength and elongation of pistons are compared and analyzed. In conventional forging process, material temperature was
and the die temperature was
for the Al 4032. The optimal condition was found as solution treatment under
for 5 hours, quenching with
water, and aging under
for 5 hours. In powder forging process, the proper composition of material was determined and optimal sintering conditions were examined. From the experiment, 1.5% of Si contents on the total weight,
of sintering temperature, and 25 minutes of sintering time were determined as the optimal process condition. For the optimal condition, the pistons had 76.4~78.3 [HRB] of hardness, and 500 [MPa] of tensile strength after T6 heat treatment.