• Title/Summary/Keyword: Deformation Wear

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The Aesthetic Values of Formalism Art to Wear (형식주의 예술의상의 미적 가치)

  • 서승미;양숙희
    • The Research Journal of the Costume Culture
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    • v.11 no.1
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    • pp.118-134
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    • 2003
  • The first purpose of this study is to take a better look it the background of Formalism art in the cultural society and to examine the aesthetic value of the formative arts of formalism architecture that are ail basically founded upon the study of Formalism. Secondly, it analyzes the aesthetic value of Formalism Art to Wear, Which can be explained as a mixture of art and fashion, by investigate to the features of art history. The results are as follows; First, Formalism Art to Wear of Simultaneity does not represent continuance but simultaneous. In other words. inside the same time and place of dimension, events art visualized without transformation. Secondly, formalism Art to Wear of Geometrical Aesthetics deals with a purely genuine atmosphere that pursues absolute perfection, composed abstract of geometrical shapes. Thirdly, Fomarlism Art to Wear of Deformation breaks analysis from balance and symmetry showing extreme transformation nil new vitality. Fourthly, Formalism Art to Wear of Space Extension experiments with post-corporeality. Post-corporeality centers the human body extension that is open to various boundaries of implosion and electronic technologies, providing us with a new Cyborg of the digital body.

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Wear Behavior of Plasma Transferred Arc Deposited Layers for Ni - and Co - base Alloy (Ni계 및 Co계 합금 PTA 오버레이용접층의 마모거동에 관한 연구)

  • 윤병현;이창희;김형준
    • Journal of Welding and Joining
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    • v.19 no.5
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    • pp.540-547
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    • 2001
  • This study has evaluated the wear behavior of PTA (Plasma Transferred Arc) Inconel 625 and Stellite 6 overlays on Nimonic 80A substrate. Nimonic 80A alloy was also included for comparison. In order to evaluate the wear performance, three-body abrasive wear test and pin-on-disk dry sliding wear test were performed. Microstructural development during the solidification of deposits is also discussed. Wear test results show that the wear rate of Stellite 6 deposit is lower than that of Inconel 625 deposit and Nimonic 80A. The sliding wear resistance of overlay deposits follows a similar trend to the abrasive wear resistance, but for Nimonic 80A. The main wear mechanisms were abrasive wear for Inconel 625 deposit, adhesive wear and delamination for Stellite 6 deposit in pin-on-disk dry sliding wear test and ploughing in three-body abrasive wear test. Cross sectional examinations of the worn surface of pin specimens after pin-on-disk dry sliding wear test implies that the plastic deformation near worn surface has occurred during the wear testing.

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Design of a Nuclear Fuel Spacer Grid Considering Impact and Wear (충격과 마모를 고려한 원자로 핵연료봉 지지격자의 설계)

  • Lee, Hyun-Ah;Kim, Chong-Ki;Song, Kee-Nam;Park, Gyung-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.31 no.10
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    • pp.999-1008
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    • 2007
  • The spacer grid set is a component in the nuclear fuel assembly. The set supports the fuel rods safely. Therefore, the spacer grid set should have sufficient strength for the external impact forces such as earthquake. The fretting wear occurs between the spring of the fuel rod and the spacer grid due to flow-induced vibration. Conceptual design of the spacer grid set is performed based on the Independence Axiom of axiomatic design. Two functional requirements are defined for the impact load and the fretting wear, and corresponding design parameters are selected. The overall flow of design is defined according to the application of axiomatic design. Design for the impact load is carried out by using nonlinear dynamic analysis to determine the length of the dimple. Topology optimization is carried out to determine a new configuration of the spring. The fretting wear is reduced by shape optimization using the homology theory. The deformation of a structure is called homologous if a given geometrical relationship holds before, during, and after the deformation. In the design to reduce the fretting wear, the deformed shape of the spring should be the same as that of the fuel rod. This condition is transformed to a function and considered as a constraint in the shape optimization process. The fretting wear is expected to be reduced due to the homology constraint. The objective function is minimizing the maximum stress to allow a slight plastic deformation. Shape optimization results are confirmed through nonlinear static analysis.

Evaluation of die life during hot forging process (열간 단조 공정의 금형 수명 평가)

  • 이현철;박태준;고대철;김병민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.1051-1055
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    • 1997
  • Hot forging is widely used in the manufacturing of automotive component. The mechanical, thermal load and thermal softening which is happened by the high temperature die in hot forging. Tool life of hot forging decreases considerably due to the softening of the surface layer of a tool caused by a high thermal load and long contact time between the tool and workpieces. The service life of tools in hot forging process is to a large extent limited by wear, heat crack, plastic deformation. These are one of the main factors affecting die accuracy and tool life. It is desired to predict tool life by developing life prediction method by FE-simulation. Lots of researches have been done into the life prediction of cold forming die, and the results of those researches were trustworthy, but there have been little applications of hot forming die. That is because hot forming process has many factors influencing tool life, and there was not accurate in-process data. In this research, life prediction of hot forming die by wear analysis and plastic deformation has been carried out. To predict tool life, by experiment of tempering of die, tempering curve was obtained and hardness express a function of main tempering curve.

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A Study on the Prediction of Die Wear using Wear Model (마멸모델을 이용한 금형마멸 예측에 관한 연구)

  • Park, Jong-Nam
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.12 no.1
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    • pp.90-96
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    • 2013
  • During the cold forming, due to high working pressure acting on the die surface, failure mechanics must be considered before die design. One of the main reasons of die failure in industrial application of metal forming technologies is wear. Die wear affects the tolerances of formed parts, metal flow and costs of process etc. The only way to control these failures is to develop methods which allow prediction of die wear and which are suited to be used in the design state in order to optimize the process. In this paper, the wear experiments to obtain the wear coefficients and the upsetting processes was accomplished to observe the wear phenomenon during the cold forming process. The analysis of upsetting processes was accomplished by the rigid-plastic finite element method. The result from the deformation analysis was used to analyse the die wear during the processes and the predicted die wear profiles were compared with the measured die wear profiles.

Wear and Friction characteristics of $Cr_2$$O_2$ coating included $SiO_2$ and $TiO_2$ ($SiO_2$$TiO_2$가 첨가된 $Cr_2$$O_3$용사코팅의 마찰 .마멸 특성)

  • 서보현;김태형;김석삼
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.11a
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    • pp.69-77
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    • 2001
  • Wear and Friction characteristics of plasma-sprayed Cr$_2$O$_3$ coating and Cr$_2$O$_3$ coating included SiO$_2$ and TiO$_2$ against SiC ball have been investigated under different loads. Worn surfaces were observed by SEM and worn surfaces were analyzed by EDS. The Friction coefficient and the Wear resistance of Cr$_2$O$_3$-5SiO$_2$-3TiO$_2$coating was less than that of Cr$_2$O$_3$ coating. The main mechanisms were plastic deformation and brittle fracture. The film on surface were made by plastic deformation and compacted wear debris. This film protect wear of coating

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A Study on the Wear of Rail by Fracture Mechanics (파괴역학을 이용한 차륜과 레일의 마모에 관한 연구)

  • 구병춘
    • Proceedings of the KSR Conference
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    • 1998.05a
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    • pp.315-322
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    • 1998
  • A two dimensional elasto-plastic finite element program taking into account contact between crack surfaces if developed in order to analyze subsurface cracking in rolling contact. But the friction between upper and lower surface of the crack is not considered. Under the assumptions of small deformation and small displacement, the incremental theory of plasticity is used to describe plastic deformation. J-integral is computed as the applied Hertzian load slides over the surface with friction. J-integral is correlated with wear rate of the rail. The propagation rate of the right tip of the surface crack is fast by 45% than that of the left side.

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A Study on the Variation of the Fretting Wear Mechanisms under Elastically Deformable Contacts

  • Lee, Young-Ho;Kim, Hyung-Kyu
    • KSTLE International Journal
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    • v.10 no.1_2
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    • pp.27-32
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    • 2009
  • In this study, fretting wear tests of nuclear fuel rods have been performed by using two kinds of spacer grid springs with a concave and a convex shape in room temperature dry and distilled water conditions. The objectives were to examine the variation of the wear mechanism with increasing fretting cycles and to evaluate the difference of the wear debris detachment behavior at each test environment. From the test results, the wear volume of each spring condition increased with increasing fretting cycles regardless of the test environments. However, the wear rate did not show a regular tendency and apparently changed with increasing fretting cycles. This is because the formation of the wear particle layer and/or the variation of the contact condition between the fuel rod and spring surfaces could affect a critical plastic deformation for detaching the wear debris. Based on the test results, the relationship between the wear behavior of each spring shape and test environment condition, and the variation of the surface characteristics are discussed in detail.

Fracture and Wear Behavior of Dental Composite Resins Containing Prepolymerized Particle Fillers (유기복합필러를 함유하는 차과용 컴퍼짓 레진의 파괴와 마멸거동)

  • Kim, Yeong-Bin;Kim, Gyo-Han;Kim, Seok-Sam;Im, Jeong-Il
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.2 s.173
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    • pp.464-471
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    • 2000
  • The fracture and wear behavior of dental composite resins containing prepolymerized particle fillers were investigated. Composite resins such as Metafil, Silux Plus, Heliomolar and Palfique Estelite were selected as specimens and contents of filler in specimens in order to evaluate the effect of prepolymerized particle fillers in fracture and wear characteristics. Ball on flat wear tester was used for the wear test at room temperature. The friction coefficient of Metafil was quite high relatively, and the wear resistances of Silux Plus and Palfique Estelite were better than those of Metafil and Heliomolar at the same experimental condition. It was found that the main wear mechanism was abrasive wear containing of plastic deformation of dental material.

Methodology of Perform Design for Reducing Tool Wear in Cold Forging (냉간 단조 금형의 마멸 감소를 위한 예비성형체 설계방법)

  • 이진호;고대철;김태형;김병민;최재찬
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1997.10a
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    • pp.164-167
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    • 1997
  • The die wear is one of the main factors affecting die accuracy and tool lifetime. It is desired to reduce die wear by developing simulation method to predict wear based on process parameters, and then optimize the process. Therefore, this paper describes disign methodology of preform for minimizing wear of finisher die in multi-stage cold forging processes. The finite element method is combined with the routine of wear prediction and the cold forging processes. The finite element method is combined with the routine of wear prediction and the cold forging process is analyzed. In order to obtain preform to minimize die wear, the FPS algorithm is applied and the optimal preform shape is found from iterative deformation analysis and wear calculation.

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