• 한국표면공학회지
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• 제33권5호
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• pp.329-338
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• 2000

In this study, as an effort to improve the brittlement of coating layer, aluminum bronze coatings formed on steel substrates by arc jet spray process were subjected to post heat treatment. After each treatment, mechanical properties such as hardness, and UTS, and microstructural characterization of the specimens were investigated. The results showed that the hardness in the coatings slightly decreased with increasing heat treatment tine and temperature. The UTS of as-sprayed coatings was 4.31kgf/$\textrm{mm}^2$ and slightly increased to 5.51kgf/$\textrm{mm}^2$ after heat treatment at $900^{\circ}C$ for 120min. On the other hand, the interdiffusion of copper and aluminum particles after heat treatment lead to decrease of the porosity density and increase the bond strength.

• Tribology and Lubricants
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• 제10권3호
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• pp.39-46
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• 1994

In order to investigate the effect of the ceramic reinforcements on the wear properties of aluminum bronze composites, Cu-8wt%Al aluminum bronze alloys reinforced with the Saffil alumina short fiber were produced by the powder metallurgical method and tested by a pin-ondisc wear testing machine. The wear surfaces of the pin specimens and discs, wear debris, and the cross sections of the wear specimens were observed by SEM. The wear mechanism according to various wear conditions and the change of microstructure in the composites were also discussed. In the results, the reinforcement of the composites with alumina short fiber was very effective at the higher applied load over 10N. The material transportation to the counter disc was observed in the alloy specimens without reinforcements. However, the composites reinforced with ceramic particles and fibers showed the resistance against the material transportation.

• 한국주조공학회지
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• 제36권6호
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• pp.202-207
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• 2016

The effects of Fe and Si additions on the microstructures and mechanical properties of aluminum bronze have been investigated. In a bar-type specimen cast in a die mold, the addition of Fe promoted the dendritic solidification of the ${\alpha}$ phase. The hardness values increased slightly in the Fe-added specimen with heat treatment, while these values was increased significantly in the specimens with Si or with combined additions of Fe and Si. When a centrifugal casting bush with combined addition of Fe and Si was heat treated, the FeSi compound within the matrix was finely dispersed, and was observed to be the origin of cup-cone type conical dimple failure in the tensile fracture surface. The mechanical properties of the heat treated centrifugal casting bushes, whose nominal alloy compositions were (Cu-7.0Al-0.8Fe-3.0Si)wt%, exhibited tensile strength of $703-781N/mm^2$, elongation of 6.6-11.7% and hardness of Hv 222.6-249.2. These high values of strength and elongation were attributed to the strengthening of the matrix due to the combined addition of Fe and Si, and to precipitation of fine the FeSi compound.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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• pp.769-775
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• 2002

The results gained as part of the study on weldability of compositions from steels, aluminium, titanium alloys in various combinations including similar and dissimilar metal bonding variants with reference to solution of specific practical problems are presented in this work. It has been shown that in the case of HIP/DB carried out with direct interaction of bonding surfaces of the most dissimilar material combinations under study, formation of high-quality joints is not assured due to various reasons. That is why development of special bonding techniques was required. The bonding techniques developed and used for HIP/DB of dissimilar steels, "Steel-bronze", "Titanium-niobium"; "Titanium-steel" and other compositions under study ensured vacuum-tight microvoid-free joints strength of a which was equal to the milder parent metal, including those obtained at reduced welding pressures. Examples of new products manufactured by HIP/DB using the technologies developed are presented.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 2003년도 추계 학술논문발표회 논문집
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• pp.184-187
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• 2003

다양한 부식 형태 준 금속부식은 대기중, 수중, 지중, 화학약품 등의 부식환경에 의해 영향을 받는다. 특히 금속 표면의 산화 반응에 의해 생성되는 녹(Rust)은 iron, steel, bronze, aluminium 등의 대상소재를 사용하는 일반 가전제품, 산업공정설비 및 각종 구조물 등에 작용하여 원재료 손상, 내구수명 저하, 구조물 붕괴, 화재 및 폭발위험성 등 대부분 안전사고로 직결되는 것이 일반적이다.(중략)

• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.714-720
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• 2003

Due to the electric power shortage in summer season and regulation of freon refrigerant, the application of gas absorption refrigeration and hot water systems are considerably increasing trend. But, this system consists of condenser, heat exchanger, supply pipe and radiator etc. which are easily corroded by acidity and dissolved oxygen and gases. In result, this system occurs scale attachment and corrosion damage like pitting and crevice corrosion. In this study, electrochemical polarization test of heat exchanger tubing material (copper, aluminium brass, 30% cupronickel(30% Cu-Ni)) was carried out in 60% lithium bromide solution at $95^{\circ}C$. As a result of polarization test, corrosion behavior by impressed potential and local corrosion. such as galvanic corrosion, pitting corrosion behavior, of tubing materials was investigated. The main results obtained are as follows: (1) The effect of pitting and crevice corrosion control of 30% cupronickel in 60% LiBr solution at $95^{\circ}C$ is very excellent. (2) Dissimilar metal corrosion of 30% cupronickel coupling to aluminium bronze is the most sensitive. (3) Current density behavior of tube materials by impressed potential is high in order of copper > aluminium brass > 30% cupronickel.

• Corrosion Science and Technology
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• 제12권5호
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• pp.233-238
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• 2013

In the case of casting materials or ductile materials for marine equipment, it is common to employ a surface modification for achieving cost reduction and improvement in strength. In particular, aluminium bronze ALBC3 exhibits excellent corrosion resistance, and thus widely used for marine application. However, application of the material under high-velocity seawater flow may induce electrochemical corrosion damage and physical damage such as cavitation erosion, leading to shorter service life of equipment. In this study, surface modification was carried out on ALBC3 alloy for different shot peening stand-off distances, and the physical hardness and electrochemical characteristics before and after modification were investigated. The results in each case showed the hardness increase in comparison with non-peened specimen, and the maximum hardness improvement(50 %) was found in 10 cm of shot-peening stand-off distance. It is observed that the electrochemical characteristics were irrelevant to application of shot peening.

• 한국안광학회지
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• 제3권1호
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• pp.39-73
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• 1998

안경테는 국제적으로 대량 교역되는 상품의 하나이다. 그렇기 때문에 오늘날 국제표준화기구(ISO-TC172/SC7/WG2)에서는 독일, 미국, 영국, 이태리, 프랑스, 스페인, 일본 등의 안경관리 전문학자, 기술자, 제조업자 등이 모여 안경테의 국제 간 원활히 하고, 소비자에게는 이익과 service를 제공하고, 제조업자에게는 생산성제고와 제조원가를 절감할 수 있는 국제적 협력을 조장하기 위하여 안경테에 관한 용어, 측정법, 부품규격, 검사 및 시험방법 등에 관한 규정을 제정하고 있다. 그런데도 불구하고 우리나라의 안경업계가 이들 회원국의 활동에 관심이 없다는 것은 안경산업의 장래를 생각할 때 암울하기만 하다. 우리나라는 1970-1980년대에 걸쳐 수출이 연평균 약 20%이상 신장되었으나 1990년대 초반부터 수출실적은 미화 2억달라를 넘어선채 정체상태를 벗어나지 못하고 있다. 그런데 정체된 안경테의 수출을 진흥시키기 위해서는 무엇보다는 신소재와 독자적인 디자인의 개발, 국제표준규격에 준한 설계와 제작, 제조기술의 혁신, 특허정보의 활용 및 국제적인 판촉활동 등이, 활발히 전개되어야 하며, 대구광역시의 섬유기술연구소와 같은 형태의 안경기술연구소 또는 안경전문기술위원회의 발족과 정부차원의 적극적인 지원이 시급한 당면과제이다. 본 논문의 궁긍적 목표는 우리나라 안경제조업자에게 ISO-Working Group2 등이 제정 발표한 안경테의 관계규정 및 규격을 소개하고 금속테를 설계 제작할 때 보완할 이론적 지침을 제시해서 설계상 결함이 없는 금속테를 제작하는데 있다.