Al-Si/Al2O3p 복합재료의 유동특성

정연조(Yeon-Jo Jung),박성하(Yeon-Jo Jung) 산업기술교육훈련학회 2011 산업기술연구논문지 (JITR) Vol.16 No.4

Al-Si alloys and Al-Si composites with Al2O3 particle-reinforcement,(Al-x%Si /y%Al2O3p(x : 6, 12,18, y : 1, 2, 3, 4, 5, Al2O3 particlesize : 50, 90μm) were fabricated by Rheocompocasting process and its fluidity was characterized in the spiral type steel mould. The fluidity of Al-Si/Al2O3p composite decreased as the Al2O3 content increased from 1wt% to 5wt% and at all the compositions of hypoeutectic, eutectic and hypoeutectic. It is found that the fluidity(F) was affected by the surface area(S) of Al2O3 rather than its volume fraction. The fluidity went down as the surface area became greater and can be expressed by periodic equations.

Al - Mg - Si - (Co, Ni) 알루미늄 합금의 고온 저주기 피로 변형 거동

김규식(K. S. Kim),성시영(S. Y. Sung),한범석(B. S. Han),박중철(J. C. Park),이기안(K. A. Lee) 한국소성가공학회 2011 한국소성가공학회 학술대회 논문집 Vol.2011 No.10

High temperature low cycle fatigue tests of new heat resistant aluminum alloy were conducted in this study. Al-Mg-Si-(Co, Ni) aluminum alloy consists of Al matrix, small amount of Mg2Si and (Co, Ni)3Al4 strengthening particles. Low cycle fatigue tests controlled by total strain were performed with strain ratio (R)=-1, strain rate=2x10<SUP>-3</SUP>s<SUP>-1</SUP> at 250℃. Fatigue limit of low cycle fatigue of this alloy showed plastic strain amplitue(Δεps) of 0.22% at the 10<SUP>3</SUP> cycles. This value was superior that that of conventional aluminum alloy such as A319. Results of fractographical observation showed that second phases, especially (Co, Ni)3Al4 particles, could act a strengthening role for low cycle fatigue behavior. It is also attempted to clarify the mechanism of high temperature low cycle fatigue behavior of Al-Mg-Si-(Co, Ni) alloy related with its micorstructure and energy dissipation anaysis.

Al 합금 금형의 열변형 제어에 의한 에너지 절감에 관한 수치해석적ㆍ실험적 연구

오율권(Oh Yool-Kwon),김용범(Kim Yong-Bum),양호동(Yang Ho-Dong) 한국태양에너지학회 2007 한국태양에너지학회 학술대회논문집 Vol.- No.-

In the study analyzed on two-dimension numerical analysis and experimentation for Al alloy mold using finite element method. To predict the numerical result of thermal strain in Al alloy mold during the cooling process, it is performed the investigation of temperature distribution, stress and displacement based on the physical properties of Al alloy. In results of this study, Al alloy mold represented rapidly cooling graph during initial 20minutes after beginning cooling process, therefore value of stress and displacement is rapidly changed during initial 20 minutes after beginning cooling process. In addition to, temperature distribution obtained by experiment confirmed corresponding pattern then compared numerical analysis with experiment. These results are contribute to make the effective and the high precision casting mold. In addition to, reduction of energy is contributed to saving time from manufacturing as possible temperature to prediction.

5000, 6000 계열 알루미늄 합금의 해수 내 캐비테이션 특성

김성종(Kim Seong-Jong),이승준(Lee Seung-Jun),김규환(Kim Kyu-Hwan) 한국마린엔지니어링학회 2010 한국마린엔지니어링학회 학술대회 논문집 Vol.2010 No.10

Al alloy has good advantages which are characteristics of environmental-friendly properties, lightweight, good weldability, durability, corrosion resistance. In addition, the advent of Al alloy ships like fishing and leisure boats are getting wider and wider to reduce fuel consumption due to lightweight. Even though corrosion and cavitation seriously occurs during navigation of vessels, the research for corrosion protection of Al alloy is not investigated since most people tend to misunderstand for Al alloy itself which has good anti-corrosion characteristics and to have insufficient knowledge about Al alloy cavitation effect caused by high speed. In this study, 5052-O, 5456-H116 and 6061-T6 Al alloy were selected and cavitation tests were carried out in sea water solution.

알루미늄표면에 금속-세라믹입자 복합첨가에 의한 내마모성개선

이규천,박성두,이영호 대한용접접합학회 1997 대한용접·접합학회지 Vol.15 No.6

The present study was aimed to correlate the microstructure and the hardness as well as the wear resistance of the metal-ceramic particulated composite layer on the pure Al plate. The composite layers were constructed by the addition of TiC particles on the surface of Al-Cu alloyed layers by PTA overlaying process. Initially, the Al-Cu alloyed layers were achieved by the deposition of Al-(25 ~ 48%) Cu alloys on the pure Al plate by TIG process. It was revealed that TiC particles were uniformly dispersed without any reaction with matrix in the composite layer. The volume fraction of TiC particles (TiC V F) increased from 12% to 55% with increasing the number of pass of composite layer. Hardnesses of (Al-48%Cu + TiC (3&4layers)) composite layer were Hv450 and Hv560, respectively, due to the increase of TiC V/F. Hardnesses of (Al-Cu + TiC) composite layers decreased gradually with insreasing temperature from 100$^{\circ}$C to 400$^{\circ}$C, and hardnesses at 400$^{\circ}$C were then reached to 1/5 - 1/10 of room temperature hardness depending on the construction of composite layers. The Specific wear of (Al + Tic) layer and Al-48%Cu alloyed layer decreased to 1/10 of the of pure Al, while the specific wear of (Al-48%Cu + TiC (4 layers)) composite layer exhibited 1/15 of that of steel such as SS400 and STS304.

자동차용 Al합금 방열기의 전지작용부식에 관한 연구

이영춘(Young-Chun Lee),김광석(Kwang-Seuk Kim) 산업기술교육훈련학회 2012 산업기술연구논문지 (JITR) Vol.17 No.2

Industrial development and income increase causes rapid increase in using fossil energy like coal, petroleum and natural gas, and it results in accelerating environmental pollution owing to the increase in emission of air pollution substance. Specially, fresh water like stream and river water is acidified and specific resistance is decreased. Therefore, corrosion damage is accelerated in radiator for automobile that is using acidified water and specific resistance is decreased water. Generally, material for radiator of automobile is composed of Al-alloy, but part of radiator material is still composed of Cu and stainless. Specially, Al-alloy replaces Cu and Cu-alloy as cooling and heating system material for light weight. Therefore, galvanic electronic cell is formed between Al-alloy, Cu and stainless for automobile radiator material, and Al-alloy corrosion is accelerated. So, in this study, galvanic corrosion test of Al-alloy coupling with stainless was carried out in distilled water, tap water, polluted environment. And thus corrosion potential and galvanic current density of Al-alloy with stainless is investigated.

DLC박막을 코팅한 초경공구의 Al합금에 대한 절삭성능 향상

이규용 한국동력기계공학회 2008 동력시스템공학회지 Vol.12 No.3

Diamond-like-carbon (DLC) coatings could be good candidates as solid lubricants for cutting tools indry maching of aluminum alloy. In this work, DLC thin films were produced as a friction reduction coating for WC-Co insert tip using the plasma ion beam deposition (PIIBD) technique. DLC coatings were also coated on Al2O3 specimens and high temperature wear tested up to 400℃ in dry air to observe the survivability of the DLC coating in simulated severe cutting conditions using a pin-on-disc tribotester Hertzian contact stres of 1.3GPa. It showed reduced friction coefficients of minimum 0.02 up to 400℃. And cutting performance of DLC coated WC-Co insert tips to Al 6061 alloy were conducted in a high speed maching center. The main problems of built-up edge formation in aluminum maching are drasticaly reduced with improved surface roughness. The improvements were mainly related to the low friction coefficient of DLC to Al alloy and the anti-adhesion of Al alloy to WC due to the inertnes of DLC.

강도해석을 이용한 Spool의 경량화 연구

장왕진(Wang Jin Jang),박종식(Jong Sik Park),정재영(Jae Young Jeong),예수해(Soo He Ye),이성범(Seong Beom Lee) 한국자동차공학회 2007 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-

Seat belt is one of the most important parts in an automobile. Seat belt consists of retractor, D-ring, buckle, anchorage. Retractor is the major part which controls spool-in or out of webbing according to acceleration pulse in seat belt. From energy efficiency and environmental point of view lighter weight car becomes hot issue in the automobile industry. In this paper, light weight study of spool was performed by 3D scanning equipment and finite element analysis. Scanning data was converted into IGES file and then improve accuracy in comparison with three dimension model. Spool is made from Al alloy. So, we implemented structural analysis of spool's material. Mg alloy is lighter than Al alloy. But analysis result showed that Al alloy and Mg alloy's stress value is close. Al alloy is increasingly being replaced with Mg alloy and this usage is expected to increase substantially.

접합툴의 형상에 따른 Al-Li합금의 마찰교반용접특성 고찰

유준태(Joon-Tae Yoo),윤종훈(Jong-Hoon Yoon),이호성(Ho-Sung Lee) 대한기계학회 2017 대한기계학회 춘추학술대회 Vol.2017 No.11

Al-Li alloys show extraordinary specific strength and have been used in Space Shuttle SLWT(Super Lightweight Tank) with application of Friction stir welding (FSW). FSW has many advantages like the absence of porosity, distortion and residual stresses which are typical defects of the fusion welding processes. The process uses a rotating tool with a profiled pin that penetrates the parts to be joined; the tool then starts to travel along the joint line. By keeping the tool rotating and moving it along the joint line to be welded, the softened material due to the frictional heat is stirred and mechanically mixed together by the rotating pin forming a weld in solid state without melting. The present work is to investigate the effect of tool configuration on the microstructure and mechanical properties of friction stir welded AA2195. Since the mechanical properties of the joint are related with development of microstructure evolution during FSW, microstructure and mechanical properties of joints were investigated for different tool configuration.

자동차 알루미늄 합금 휠의 진동특성에 관한 연구

김병삼(Byoung-Sam Kim) 한국생산제조학회 2005 한국생산제조학회지 Vol.14 No.3

The styling of automobile wheels and their effect on vehicle appearance has increased in importance in recent years. The wheel designer has been given the task of insuring that a wheel design meets its engineering objectives without affecting the styling theme. The wheel and tire system is considered as a vehicle component whose dynamic modal information of the tire/wheel system are employed in the modal synthesis model of the vehicle. The vibration characteristics of a automobile wheel play an important role to judge a ride comfort and quality for a automobile. In this paper, the vibration characteristics of a Al-alloy and steel wheel for automobile are studied. Natural frequency, damping and mode shape are determined experimentally by frequency response function method. Results show that wheel material property, size and design are parameter for shift of natural frequency and damping.