• 한국식품영양과학회지
• /
• 제13권1호
• /
• pp.15-21
• /
• 1984

국산 retort pouch의 실용 가능성을 확인하기 위하여 수입하여 사용되고 있는 외국제품과의 성능을 비교한 실험 결과를 요약하면 다음과 같다. 가) 공전(空錢)상태에서의 물성강조 시험결과는 국산 제품(SM-4ply, SM-3ply)과 외국제품(JP-4ply JP-3ply)이 거의 동일한 강도를 유지하고 있었다. 나) Model식품을 이용한 pouch 물성(物性)강도의 경시적 변화결과도 외국제품에 비교하여 손색이 없었으며 laminate강도(적층박리강도)에서는 국산제품이 다소 우수한 결과를 보였다. 다) 실용제품(寶用製品)(retort curry and (packea rice)의 생산(生産)을 위한 실질적인 제조과정을 통하여 pouch의 내열성 및 내용식물의 보존성에 대하여 조사한 결과 국산제품과 외국제품간의 성능차이는 없었으며 이들 공시(供試) pouch는 $135^{\circ}C$ 가열살균에 견딜 수 있는 내열성과 상온유통과정에서 장기 보존이 가능함을 확인 할 수 있었다. 라) 국산 retort pouch의 위생적 안전성은 보사부 고시 제 30호(78년 7월 24일)의 시험방법에 의하여 시험한 결과 규정에 부합되고 있었다.

• International Journal of Korean Welding Society
• /
• 제2권1호
• /
• pp.15-20
• /
• 2002

This paper describes the weldability and mechanical behavior of JIS S45C medium carbon steel (corresponding to KS SM45C and SAE 1045) for machine structures in CW Nd:YAG laser welding. In general, medium carbon steels have a limited application to the industrial fields in spite of good mechanical characteristics. This is due to welding difficulty because of the high carbon contents and impurities in this material. Therefore, in this study the laser weldability of medium carbon steel with adjusted contents of S and P has been investigated in order to extend the application to medium carbon steels. Several experiments and numerical simulations have been conducted to determine the characteristics of mechanical behavior in CW Nd:YAC laser welds. The results of the simulations concur with the experiment results. From the result of this study, the application possibility of CW Nd:YAG laser welding to medium carbon steel has been confirmed. Also, the appropriateness of mechanical behavior simulation has been verified to analyze and predict the welding phenomena.

• Nuclear Engineering and Technology
• /
• 제18권1호
• /
• pp.1-8
• /
• 1986

SNU 1.5MV 반데그라프 가속기의 표적상자 전단에서 사용될 자기 4극 렌즈를 제작하고 그 광학적 특성을 측정 및 분석하였다. 렌즈의 칫수는 자극 길이 180mm, 구경 반경 25mm, 자극편 반경 28.75mm이며 자극과 철심의 재료로는 탄소강 KS-SM40C를 사용하였다. 코일은 자극 당 480회 감아 공냉식을 채택하고 있다. 제작한 렌즈에 직류 전류 2.99$\pm$0.03A를 흘리며 Hall 탐침소자를 써서 r,$\theta$,z의 각 방향에 대해 여러 지점에서 자장 요소 $B_{\theta}$, $B_{\gamma}$을 측정하였다. 측정된 자료에 대한 면적 적분과 직교성 다항함수 fitting을 통하여 렌즈 중심에서 자장 구배 G=566.3$\pm$2.1 gauss/cm, 렌즈축 상에서 유효길이 L=208.3$\pm$1.44mm로 나타났다. 렌즈의 다극 요소는 최소자승법을 써서 20극까지 결정하였다. 결과로서 렌즈 중심의 18mm 반경 이내의 영역에서 6극 요소 대 4극 요소의 비는 1.4$\pm$0,9% 이하이고, 기타 다극 요소들은 모두 0.5% 미만임을 얻었다.

• 소성∙가공
• /
• 제18권2호
• /
• pp.166-171
• /
• 2009

In this paper, a basic study on micro cutting process with SM20C at low temperature environment was performed. In macro cutting fields, the cryogenic cutting process has been applied to cut the refractory metal but, the serious problem may be generated in micro cutting fields by the cryogenic environment. However, if the proper low temperature is applied to micro cutting area, the cooling effect of cutting heat is expected. Such effect can make the reduction of tool wear and burr formation. For verifying this possibility, the micro cutting experiment at low temperature was performed and SEM images were analyzed.

• 대한기계학회논문집
• /
• 제10권4호
• /
• pp.477-486
• /
• 1986

본 연구에서는 SM20C를 모재로 하여 입경의 크기가 다른 3종의 복합조직강을 제작 동일한 분위기에서 저 및 고사이클 전영역에 걸쳐 피로특성을 검토하고져 한다. 제일보는 그 중 저사이클특성에 대한 보고이다. 일반적으로 저사이클 피로현상은 재 료가 탄소성 상태하에서 전위, 미소크랙, 보이드(void) 등의 인자가 복합적으로 작용 하여 발생함으로 변형률속도, 제어파형, 온도, 시험방법 및 분위기에 따라 많은 영향 을 받는다. 따라서 본 연구에서는 두가지 실험방법을 사용, 응력-변형율거동을 검토 복합조직강의 피로특성과 입경크기가 피로거동 및 강도에 미치는 영향을 비교 고찰하 였다.

• 한국정밀공학회지
• /
• 제19권2호
• /
• pp.228-236
• /
• 2002

In this study, the carbon steels, SM20C were machined with the tungsten carbide tipped circular saw to clarify the cutting-off characteristics in terms of tool wear. The results show that an improved performance in view of both the tool wear and the cutting efficiency was obtained by using oil base cutting fluid at the cutting speed of 100m/min with the feed of 0.06mm/tooth. The rake angle of 10$^{\circ}$ , clearance angle of 8$^{\circ}$ , nose radius of R0.1mm, and end cutting edge champer of 0.1mm$\times$25$^{\circ}$ are believed as the best tool geometries. The tool wear decreases due to using the saw of the disk of STS5 and the tool material of P30.

• 한국생산제조학회지
• /
• 제5권2호
• /
• pp.38-45
• /
• 1996

This study was focused on the prediction of the approprite tool life by clarifying the correlation between progressive drill wear and AE signal. on drilling SM45C the following results have been obtained; RMSAE, AE CUM-CNTS had a tendency to increase slowly according to wear size, at 1000rpm, 150mm/min However, these increased suddenly in the range of 0.20~0.22mm wear, about 102 holes and had a tendency to go up and down until the drilling was impossible. The sudden increase of AE signals shows that something is wrong and it is closely connected with drill wear and chipping. It also makes the working surface bad From the above results, AE signals could be used to monitor the drill's condition and to determine the right time to change tools.

• 한국정밀공학회지
• /
• 제20권1호
• /
• pp.179-186
• /
• 2003

This paper is to investigate the wear behavior of submerged-arc claddings by the wear test with a ball-on-disk type wear testing machine in air. The specimens were clad with Stoody105 alloy wire on a medium carbon steel (SM45C) substrate by submerged-arc cladding process under different welding parameters. The wear behavior of the cladding through ball-on-disk test has been studied under the wear load from 5 to 16 N and the sliding speed from 8 to 35 cm/s. The weight loss of the specimen was measured. Scanning electron micrographs of the worn surface show a layer of oxide film formed on the worn surface. Oxidation wear mechanism controls the wear process. The spatting of the oxide is caused by the repeated rubbing fatigue mechanism.

• 열처리공학회지
• /
• 제19권1호
• /
• pp.20-29
• /
• 2006

Wear behaviour of B.390 aluminum alloy with different particle sizes of primary Si against a SM45C counterface was studied as a function of wear load and sliding velocity, using pin-on-disk apparatus under dry condition. The wear rate of specimen with fine primary Si particles showed increased wear resistance at high wear load, on the other side wear resistance of coarse primary Si particle size was improved at low wear load. As the compressive residual stress in the matrix increased remarkably by liquid nitrogen(LN) treatment, wear resistance of the LN treated specimen was more excellent than that of T6 treated specimen.

• 한국기계가공학회지
• /
• 제11권5호
• /
• pp.13-20
• /
• 2012

In order to clarify the effect of overload on crack growth behaviors, fatigue tests for overload were carried out for round plain specimens of SM45C steel. In the experiment, typical semi-elliptical crack shape was found and further crack growth behaviors were tested. Using three types of single overload fatigue tests, Crack growth retardation phenomenon were examined. The growth rate of surface crack(da/dN) during retardation period was analyzed in terms of ${\Delta}K$ and ${\Delta}K_{eff}$. On the growth rate of surface crack analyzed by ${\Delta}K$, the dependence of overload stress levels appears. However, on the growth rate by ${\Delta}K_{eff}$ obtained by Willenborg analysis, there is a non-liner relationship between da/dN and ${\Delta}K_{eff}$ with narrow scatter band.