C/V 흑연주철의 조직과 기계적 성질에 미치는 Sb 첨가효과

최양진,강인찬 ( Yang Jin Choi,In Chan Kang ) 한국주조공학회 1987 한국주조공학회지 Vol.7 No.1

In order to study the infuence of Sb addition on the compacted vermicular graphite cast iron(C/V) and gray cast iron(GC), these specimen which had different Sb content(0-0.l wt.%) were prepared. these specimen were tested for microstructure and mechanical properties. The result from this study are as follows. For C/V and GC, the microstructure of graphite appeared to be finer with increasing Sb content more than 0.06wt.%. Ferrite disappeared from the matrix with addition of Sb more than 0.06wt. % in GC and more than 0.08wt.% in C/V. The size of the eutectic cell in GC was 4.5 to 7 times larger than that in C/V, but the decreasing tendancy of its size was more remarkable in GC than in C/V with increasing Sb content. The abrasion speed corresponding to the maximum amount of abrasion in the nabrasion test was found to be 1.37m/sec. GC sample weared 3.6 to 21 times faster than those of C/V did. the amount of abrasion demeased remarkably with Sb addition, and the abrasion rate was constant with Sb content over 0.04wt.%.

구상흑연주철의 피절삭성과 내마모성에 미치는 Boron 첨가의 효과에 관한 연구

최양진,이병엽,권혁무,백상한,박용진 ( Yang Jin Choi,Byung Yehp Lee,Hyuk Mu Kwon,Sang Han Baek,Yong Jin Park ) 한국주조공학회 1994 한국주조공학회지 Vol.14 No.1

N/A It is very important to obtain high performance ductile iron by addition a small amount of alloying elements. In this study, to improve the characteristics of small piston ring tasted from ductile iron melt a small amount of boron(0∼0.008wt.%) that is powerful carbide stabilizer was added in ductile iron, and inspected it`s effects on the microstructure, wear resistance, machinability and mechanical properties. The results obtained from this study are as follows. 1. As the amount of boron increased to 0.04wt.%, the machinability of ductile iron is increased, and if the amount is in excess of 0.04wt.% the machinability is decreased conversely. 2. The wear resistance of ductile iron is improved by boron addition. 3. The recommended ladle addition of boron amount ranges from 0.04wt.% to 0:06wt.% for the use of small piston ring.

B 및 P 첨가에 의한 구상흑연주철의 특성변화

최양진,박용진,이병엽 ( Yang Jin Choi,Yong Jin Park,Byeong Yehp Lee ) 한국주조공학회 1996 한국주조공학회지 Vol.16 No.4

N/A Boron is known of the powerful pealrite stabilizing elements in cast irons. In this study, to improve the wear resistance of ductile cast iron, a small amount of phosphorus-boron complex additive was added. Five melts having different compositions of phosphorus and boron were tasted into Y-type CO₂mould and inspected thear microstructure, mechanical and thermal properties, respectively. The results obtained from this study are as follows ; 1. Although the wear resistance of ductile cast iron is raised with the addition of B and P, its effect are more remarkable when they areadded simultaneously. For this reason the recommended complex addition amount is in the range of 0.04%B and 0.4%P. 2. Although the hardness of the ductile cast iron is increased with the addition of B and P it`s machinability is improved if additive amount is not over 0.04%B and 0.4%P. 3. The value of thermal expansion coefficient of the ductile cast iron is decreased with the addition of B and P, and is lowest in heat 5(0.04%B and 0.4%P).

Boron 첨가가 박육 구상흑연주철의 미세조직과 기계적 성질에 미치는 영향

백상한,최양진,김영환,박용진 ( Sang Han Baek,Yang Jin Choi,Young Hwan Kim,Yong Jin Park ) 한국주조공학회 1994 한국주조공학회지 Vol.14 No.2

N/A Effects of boron addition on microstructure and mechanical properties of thin ductile cast iron have been investigated. The amounts of boron addition and the thickness of specimen have been varied from 0 to 0.4wt% and ø13㎜, ø10㎜ and ø6㎜, respectively. As the casting thickness decreased, the average diameter of spheroidal graphite was decreased and hardness of the cast iron increased. By adding boron, tensile strength increased and had maximum which is about 30∼40% higher than ordinary ductile cast iron with 0.17wt%B addition. With boron adding more than 0.2wt%, ferrite and pearlite gradually transformed to boron carbide, resulting in decrease of tensile strength. The elongation decreased continuously with boron content. The addition of boron about 0.002∼0.4wt% improves the wear resistance and tensile strength of thin ductile cast iron.

유동층을 이용한 주물사의 재생에 관한 연구

백고길,최양진 ( Ko Kil Baek,Yang Jin Choi ) 한국주조공학회 1992 한국주조공학회지 Vol.12 No.6

N/A For the last 2 decades, the bonding materials for the foundry sand and the foundry equipments with high performance have been developed and employed in the foundry shops. In those periods, the furan resins hardened in higher temperature have been replaced with the self-hardened ones in the room temperature. Simultaneously the various reclamation methods of the self-hardened furan resin sand have been developed in order to get the clean working environments, the reduction of solid wastes and the lower of production cost in the foundry. In this experimental study, the combustion reclamation method using the fluidized bed among the various methods was studied in order to reduce the L.O.I. and /or N₂ gas due to the deposition of the furan resins and the hardeners. Comparing the results of this experimental combustion reclamation method with those of the employed pneumatic method, the Surface Stability Index of the specimen made by combustion method is 30% higher than that of the latter one and L.O.I. decreases about 30%. The reclamation temperature of 650℃ in this experimental fluidized bed would be recommended in the viewpoints of the reclamation period, the fuel consumption and the residual quantity of the furan resin. The formula determining the minimum fluidizing velocities according to the temperatures in the fluidized bed has been obtained.

박육구상흑연주철에 있어서 Mo 첨가 및 주물두께의 영향에 관한 연구

송병우,최양진,김영환,박용진 ( Byeong Woo Song,Yang Jin Choi,Yong Hwan Kim,Yong Jin Park ) 한국주조공학회 1993 한국주조공학회지 Vol.13 No.2

N/A In this study, the effect of Mo addition on the microstructure and mechanical properties of ductile cast iron have been investigated. The amounts of Mo and the thickness of specimen have been varied from 0 to 4.79wt% and 13㎜, 10㎜ and 6㎜, respectively. As the casting thickness decreases, the average size of spheroidal graphite is decreased and the hardness increases. By increasing the Mo content, the tensile strength of ferrite and pearlite matrix increases and shows maximum which is about 30∼40% higher than ordinary ductile cast iron. After the maximum, adding more Mo results in gradual transformation of ferrite and pearlite to bainite and thus tensile strength decreases again. The elongation decreases continuously with Mo content. The addition of Mo about 0.5∼1.0wt% improves the wear resistance and tensile strength of thin ductile cast iron.

고 Si-P 첨가가 박육구상흑연주철의 미세 조직과 기계적 성질에 미치는 영향

박용진,최양진,박인선,김영환,이효상 ( Yong Jin Park,Yang Jin Choi,In Sun Park,Young Hwan Kim,Hyo Sang Lee ) 한국주조공학회 1995 한국주조공학회지 Vol.15 No.6

N/A Effects of high Si-P addition on microstructure and mechanical properties of thin ductile cast iron have been investigated. The amount of silicon addition have fixed on 4.0wt% and the amounts of phosphorus addition and thickness of specimen have been varied from 0.05 to 0.8wt% and ø13㎜, ø10㎜ and ø6㎜, respectively. As the casting thickness decreased, the average diameter of spheroidal graphite was decreased and the hardness of the cast iron increased. By adding P, the average diameter of spheroidal graphite was increased and the count of the spheroidal graphite was decreased continuously. And the tensile strength and the elongation was decreased, and the hardness was increased. With the P added more than 0.2wt%, the abraded amount was decreased significantly. The addition of P improved the wear resistance and the hardness of thin ductile cast iron.

대전공업대학 발전방안에 관한 연구

백고길(Ko Kil Back),최양진(Yang Jin Choi),송하영(Ha Young Song) 대한공업교육학회 1990 대한공업교육학회지 Vol.15 No.2

TAEJON University of Technology which was installed in 1984 as an Open University of Korean style, the Institute of Higher Education in the Continuing Education and the Recurrent Education based on the Life-long Education has been studied from a developing point of view. The major results are as follows: (1) In the questionnaire survey on the Technologist Education in the Choongchong district concerned with the College-Industry Cooperation, the curriculum should be provided for the scheme to lessen the lack of the practical talents in the executive abilities for his/her charge. Furthermore, the entrusting education for the continuing and recurrent education for the on-the-job students should be prepared and implemented. (2) In the activated strategies in the College-Industry Cooperation, the function and business of the College-Industry Liaison should be reinforced as well as the preparation and the execution of the programs of the College-Industry Cooperation. (3) In the development of Technologist Curricula, the curriculum module for educating the technologists has been set up and the curricula in the fields of the Factory Automation and the Machnine Design have been developed.

강섬유 혼입 콘크리트의 전단강도 추정 모형 개발

박주경 ( Park Ju-kyung ),권오훈 ( Kwon Oh-hun ),곽경헌 ( Kwak Kyung Hem ),최양진 ( Choi Yang-jin ),정태영 ( Chung Tae-young ) 한국구조물진단유지관리공학회 2007 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.11 No.2

This study took a look at the tendency of studies by collecting and analyzing the data of the advanced studies on SFRC, and facilitated it on the learning data required in the model development. In addition, by applying the diverse nerve network model and various algorithms to develop the optimal nerve network model appropriate to the dynamic characteristics. The accuracy of the developed nerve network model was compared with the experiment data value of other researchers not utilized as the learning data, the experiment data value undertaken in this study, and comparison made with the formulas proposed by the researchers. And, by analyzing the influence of learning data of nerve network model on the estimation result, the sensitivity of the forecasting system on the learning data of the nerve network is analyzed.

강섬유 혼입 콘크리트의 휨강도 추정 모형 개발

박주경 ( Park Ju-kyung ),권오훈 ( Kwon Oh-hun ),곽경헌 ( Kwak Kyung Hern ),최양진 ( Choi Yang-jin ),정태영 ( Chung Tae-young ) 한국구조물진단유지관리공학회 2007 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.11 No.1

This study took a look at the tendency of studies by collecting and analyzing the data of the advanced studies on SFRC, and facilitated it on the learning data required in the model development. In addition, by applying the diverse nerve network model and various algorithms to develop the optimal nerve network model appropriate to the dynamic characteristics. The accuracy of the developed nerve network model was compared with the experiment data value of other researchers not utilized as the learning data, the experiment data value undertaken in this study, and comparison made with the formulas proposed by the researchers. And, by analyzing the influence of learning data of nerve network model on the estimation result, the sensitivity of the forecasting system on the learning data of the nerve network is analyzed.