• Journal of Ocean Engineering and Technology
• /
• v.4 no.1
• /
• pp.110-119
• /
• 1990

This study is concerned about the stress concentration factor measurement by photoelastic method, for the case of two circular holes arrangement in 3mm semi-infinite plate under tensile load, the ratio of those two circular holes diameter, the ratio of distance apart from circular holes to breadth and the two holes arrangement angle with loading direction were varied. Besides, the measured stress concentration by photoelastic method around one circular hole was compared with that by strain-gage method.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2001.10a
• /
• pp.269-274
• /
• 2001

Applications of Brazing in the studying fields such as High-Speed Machining are very increasing in various industry fields. Therefore, Applying to the fracture mechanics by numerical analysis method is very important to analyse the crack problem Dissimilar Materials in Brazed Interface. In this study, Stress intensity Factor (S.I.F) is analysed to investigate crack behavior on the crack tip of dissimilar materials in brazed interface such as a Hardmetal and a HSS by two dimensional(2-D) Boundary Element Method (BEM). Kelvin's solution was used as a fundamental solution in BEM analysis and stress extrapolation method was used to determine Stress Intensity Factor.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.8 no.1
• /
• pp.35-44
• /
• 1999

In a view point of earth environmental protection and social requirement, adhesively bonded structures of aluminum alloys have become to be employed for the purpose of decreasing fuel ratio by weight reduction and to improve performance in various engineering fields such as aircrafts, automobiles, rolling stocks and so on. In spite of such wide applications in adhesively bonded structures of aluminum alloys, the quantitative fracture criterion and evolution method of its bonded strength have not been established yet. The objective of this paper is to establish fracture criterion considering stress singularity at interface edges in adhesively bonded structures of aluminum alloys. Through the analyses of boundary element method and static fracture experiments with three different types of specimens in the adhesively bonded joints of aluminum alloys, its fracture criterion was proposed and discussed about strength evolution of adhesively bonded structures.

• Journal of Biomedical Engineering Research
• /
• v.13 no.4
• /
• pp.353-362
• /
• 1992

The stress distribution of bone is altered by the rigid bone plate, sometimes resulting in unfavorable osteoporosis. The rigidity and the biocompatibility are important factors for the design of prosthesis. However, it is also necessary to consider the effect on the bone remodeling. In this paper, it is attempted to establish an approximate and simple method to predict the trend of the configuration of surface bone remodeling for the case of a bone plate using stress analysis. Thus, three dimensional finite element model of plated-human femur is generated and simulated. In addition. the stress difference method (SDM) is introduced and attempted to demonstrate the configuration of surface bone remodeling of the plated-human femur. The results are compared with those of invivo tests and the feasibility of the stress difference method is discussed.

• Tribology and Lubricants
• /
• v.13 no.4
• /
• pp.66-70
• /
• 1997

Thin films and coating technologies are used for an enormous and diverse set of application including mechanical and automotive components. Many of these applications require the various properties which can be used for decreasing wear, friction and cost, and increasing the long life. The relationship between the load and the stress is usually nonlinear. The material is often apt to deform plastically under the low loads. Numerical method may be used for some simple problems of the coating. If the property of coating and base materials are inhomogeneous and the geometry is complex, the numerical method may be recommended. In this paper, the contact normal stress of the coating layer has been solved using finite element method.

• Transactions of Materials Processing
• /
• v.3 no.2
• /
• pp.215-228
• /
• 1994

The purpose of this paper is to pursue a general method to determine both the flow stress of a material and the friction factor by ring compression test. The materials are assumed to obey the expanded n-power hardening rule including the strain-rate effect. Ring compression is simulated by the rigid-plastic finite element method to obtain the database used in determining the flow stress and friction factor. The Simulation is conducted for various strain hardening exponent, strain-rate sensitivity, friction factor, and compressing speed, as variables. It is assumed that the friction factor is constant during the compression process. To evaluate the compatibility of the database, experiments are carried out at room and evaluated temperature using specimens of aluminum 6061-T6 under dry and grease lubrication condition. It is shown that the proposed test method is useful and easy to use in determining the flow stress and the friction factor.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2006.05a
• /
• pp.132-135
• /
• 2006

Injection molding is a flexible production technique for the manufacturing of polymer products, but introduces residual stresses. Residual stresses in a structural material or component are those stresses which exist in the object without other external loads. The layer removal and hole drilling method are used for the measurement of residual stress in injection molded polystyrene part. The hole drilling method is potentially more flexible for determining residual stress in complex geometries and can be used as an adoptable technique for the measurement of residual stress in polymeric materials. Results obtained by experiments agree with each other.

• Journal of Korean Association for Spatial Structures
• /
• v.6 no.3 s.21
• /
• pp.131-137
• /
• 2006

This study presents a new stress analysis method to be substituted for the elastic analysis in such a plastic design procedure. This method is accompanied by an efficient mathematical tool which can be easily handled by personal computer. The method also easily accepts arbitrary strategies by the designer for selection member size.

• Proceedings of the KSME Conference
• /
• 2003.04a
• /
• pp.285-291
• /
• 2003

An experimental method to measure Q-parameter in-situ is described. The basic idea comes from the fact that the side necking near a crack tip indicates the loss of stress triaxiality, which can be scaled by Q. From the out-of-plane displacement and the in-plane strain near the surface of side necking, stress field averaged through the thickness is calculated and then Q is determined from the difference between the stress field and the HRR field corresponding to the identical J-integral. To prove the validity, three-dimensional finite element analysis has been performed for a CT configuration with side-groove. Q-value which was calculated directly from the near-tip stress field is compared with that determined by simulating the experimental procedure according to the proposed method, that is, the Q-value determined from the lateral displacement and the inplane strain. Also, the effect of location where the displacement and strain are measured is explored.

• Journal of KSNVE
• /
• v.10 no.4
• /
• pp.686-691
• /
• 2000

In this paper a computer aided analysis method is proposed for durability assessment in the early design stages using dynamic analysis, stress analysis and fatigue life prediction method. From dynamic analysis of a vehicle suspension system, dynamic load time histories of a suspension component are calculated. From the dynamic load time histories and the stress of the suspension component, a dynamic stress time history at the critical location is produced using the superposition principle. Using linear damage law and cycle counting method, fatigue life cycle is calculated. The predicted fatigue life cycle is verified by experimental durability tests.