• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 추계학술대회논문집
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• pp.32-35
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• 2004

The development of automotive rear chassis part using tube forming process has advantage of increase in part durability and decrease in its weight. We developed tubular type rear CTBA(Coupled Torsion Beam Axle) part with 60K high strength steel developed by POSCO in this project. The result was demonstrated that tubular type CTBA shows excellent durability performance and $10\%$ weight reduction compared with V-beam type CTBA in our work. Furthermore, we will adapt this technology to mass production and apply to the other chassis parts.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.43-45
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• 2005

For application of advanced high strength hot-rolled steels (i.e. DP590, DP780) to automotive lightweight chassis parts, various technologies from design to forming test, optimization of welding condition and investigation of coating properties were tried. The target part of this study was automotive rear sub frame and we could make $16.8\%$ weight reduction by reducing the material thickness and optimizing the design. In addition, the formability and weldability of the newly developed AHSS, DP780, were evaluated.

• 한국공작기계학회논문집
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• 제17권1호
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• pp.92-97
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• 2008

The safety and the durability of the shock absorber as an automotive chassis part under the fatigue load can be predicted in this study. The fatigue life becomes constant from 0.5 to 0.75 at the change of load which is the amplitude load divided by average load. But its life is sharply decreased at the change of load from 0.75 to 1.5. The influence of fatigue life according to the change of load can be predicted by these results. As the value of maximum damage is 9.61 at the middle part of upper side on shock absorber under the concentrated load, there is the greatest possibility of destruction at this part. The spring of shock absorber becomes nearly the state of pure shear and the uniaxial or biaxial stress exists at the rest part of it under the fatigue load.

• 한국자동차공학회논문집
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• 제20권3호
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• pp.1-6
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• 2012

This paper developed the chassis part as micro-alloyed steel with high toughness. The performance of micro-alloy steels are superior to similar heat treated steels. The strengthening effects of vanadium make micro-alloyed steels particularly suited for high-strength-steel applications. The disadvantages are that ductility and toughness are not as good as quenched and tempered (Q&T) steels. Precipitation hardening increases strength but may contribute to brittleness. Toughness can be improved by reducing carbon content and titanium additions. dispersed titanium nitrides (TiN) formed by titanium additions effectively prevents grain coarsening. Grain refinement increases strength but also improves toughness. For the chassis parts using high toughness micro-alloy steel, it had proven superior to a plain steel forging by static strength test and endurance test.

• International journal of advanced smart convergence
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• 제11권3호
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• pp.215-221
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• 2022

In the manufacturing process of the bus treated as the commercial vehicle, after making the bare chassis which is the basic frame of the vehicle body, the part in which passengers ride is connected. In addition, the necessary parts such as the engine and transmission required for the operation of the bus are connected to the bare chassis. The element connecting the parts such as the boarding part of the passengers, the engine, the suspension and the transmission is the bracket. The device required for driving and operating the vehicle is mounted on the bare chassis using the bracket, which should ensure stability during bus operation. In this study, we were performed stress analysis to evaluate the stability of three types of brackets connecting the bare chassis of a new type of 30-seater bus in the development process and components required for driving and operation. The stress analysis should be preceded by the analysis of boundary conditions considering the loads applied to the brackets according to the material of the bracket to be analyzed and the driving type of the bus. The finite element model for structural analysis of brackets according to the driving type of the bus was used by Altair's Hypermesh 2017, and the solver used for structural analysis was Altair's Optistruct. The stress analysis was performed to present the safe and vulnerable parts of the three brackets.

• Tribology and Lubricants
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• 제25권2호
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• pp.120-124
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• 2009

In automobile chassis system, several environmental factors weaken durability of automobile's components. The environmental factors are temperature, humidity, intensity of radiation and dust particle inflow. Especially, dust particle inflow leads to increase in friction and wear of automobile's components. The wear of automobile's component leads to increase in noise and exerts a bad influence on life of components. In this study, dust particles were investigated for study on the influence of dust particle inflow. Dust particles are collected on urban area, rural area and highway in China. The size of dust particle is analyzed using the image plus program, and the element of dust particle is analyzed using the SEM and EDX. The elements of dust particle are $SiO_2$ and $Al_{2}O_{3}$. The other elements(Na, Ca, Cl etc..) are detected on urban area and highway.

• 융복합기술연구소 논문집
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• 제4권2호
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• pp.67-70
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• 2014

Recently EU has been recognized that there is a difference of emission quantity between emission certification test mode and real-road driving test. Accordingly the European Commission is currently preparing to require real-road testing as part of the passenger car type-approval process in the EU. vehicle manufacturers from 2017 are expected to test new vehicles not only under laboratory conditions but also on the real-road, using PEMS equipment. Therefore the purpose of this study is to analyze the emission and Fuel Economy of CVS-75 mode test using chassis dynamometer and RDE test using PEMS equipment by PHEV passenger car.

• 한국생산제조학회지
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• 제20권4호
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• pp.427-433
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• 2011

Chassis part in automotive body is affected by fatigue load at driving on the ground. Universal joint on this part is influenced extremely by the fatigue load. Fatigue life, damage and natural frequency are analyzed at universal joint under nonuniform fatigue load. The york part at universal joint is shown with the maximum equivalent stress and displacement of 60.755 MPa and 0.21086 mm as strength analysis. The possible life in use in case of 'SAE bracket' is the shortest among the fatigue loading lives of 'SAE bracket', 'SAE transmission' and 'Sine Wave'. The damage at loading life of 'SAE transmission' is the least among 3 types. The frequency of damage in case of 'Sine Wave' is 0.7 with the least among 3 fatigue loading life types but this case brings the most possible damage as 80% at the average stress of 0. Natural vibration at this model is analyzed with the orders of 1'st to 5'th and maximum frequency is shown as 701.73 Hz at 5'th order. As the result of this study is applied by the universal joint on chassis part, the prevention on fatigue damage in automotive body and its durability are predicted.

• 한국산학기술학회논문지
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• 제8권3호
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• pp.427-431
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• 2007

본 연구를 통하여 피로를 받는 자동차 섀시 부분인 암에 대한 안전성과 내구성을 예측할 수 있다. 하중의 변화는 하중의 진폭을 평균 하중으로 나눈 값으로서 하중의 변화가 0.5부터 0.75에서는 급격하게 피로 수명이 감소되나 0.75이상부터 1.5까지는 그 수명이 완만하게 변화된다. 이러한 결과들에 의하여 하중의 변화에 대한 피로 수명의 영향을 예측할 수 있다. 또한 집중 하중을 받는 로드 엔드의 연결 부분에서 최대의 손상값인 2.2를 보이고 있어 이 연결 부분에서 파단의 가능성이 가장 큼을 보이고 있다. 또한 이 부분에서는 $-6.93{\times}10^{-3}$의 압축 변형율로서 최대의 압축 응력이 349 Mpa이 되어 압축으로 인하여 파단 될 가능성이 큼을 알 수 있다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.320-325
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• 2006

The phenomenon of squeal in disc brakes has been, and stin is, a problem for the automotive industry. Extensive research has been done in an attempt to understand the mechanisms that cause it and in developing design procedures to reduce it to make vehicles more comfortable. In this paper, the study on squeal noise of disc brake is performed using complex eigen-value analysis, The first part describes the chassis-dynamometer and the testing procedure, and second part explains how the analysis is performed and shows some of the results from typical squeal tests. Finally, to reduce squeal nose of disc brake is investigated by the effects of brake design parameter.