http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 강정충 ( T . W . Park (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Cu를 함유한 HSLA-100강 용접 열영향부의 미세 조직 및 인성
박태원,심인옥,김영우,강정충 ( T . W . Park,I . O . Shim,Y . W . Kim,C . Y . Kang ) 한국열처리공학회 1995 熱處理工學會誌 Vol.8 No.1
A study was made to characterize the microstructures and mechanical properties of the base metal and the heat-affected zone(HAZ) in Cu-bearing HSLA-100 steel. The Gleeble thermal/mechanical simulator was used to simulated the weld HAZ. The relationship between microstructure and toughness of HAZ was studied by impact test, O.M, SEM, TEM, and DSC. The toughness requirement of military specification value was met in a.ll test temperatures for the base metal. The decrease of HAZ toughness comparing to base plate is ascribed to the coarsed-grain and the formation of bainite. Obliquely sectioned Charily specimens show that secondary crack propagate easily along bainite lath. Improved toughness(240J) at HAZ of Tp₂=950℃ is due to the fine grain, and reasonable toughness(160∼200J) in the intercritical reheated HZA is achieved by the addition of small amount of carbon which affects the formation of M-A. Cu precipitated during ageing for increasing the strength of base metal is dissolved during single thermal cycle to 1,350℃ and is precipitated little on cooling and heating during subsequent weld thermal cycle. Thus, the decrease of toughness does not occur owing to the precipitation of Cu.
-
Cu를 함유한 저합금 고장력강의 미세 조직에 미치는 열처리의 영향
박태원,심인옥,김영우,강정충 ( T . W . Park,I . O . Shim,Y . W . Kim,C . Y . Kang ) 한국열처리공학회 1995 熱處理工學會誌 Vol.8 No.2
A study was made to examine the effects of heat-treatment on the microstructures of Cu-bearing HSLA steels. The details of microstructures were studied by using optical microscopy(OM), transmission electron microscopy(TEM) and hardness test. The as-rolled microstructure of HSLA-A consists of ferrite(α) whereas that of HSLA-B consists of needle-shaped phase. The difference in microstructure can be ascribed to the different amount of Ni, Mn, Mo, Cu which affect the hardenability. The sustenite grain size is very small up to 1000℃ owing to the Nb-precipitates. As the austenitizing temperature increases above 1000℃, the austenite grain grows rapidly. There are two hardness peaks in the hardness versus temperature curve, at 500℃ and at 675℃(HSLA-A), 725℃(HSLA-B). The peak at 500℃ result from the formation of Cu-precipitates and second hardness peak is created due to the formation of M-A constituents. The hardness decrease in HSLA-B steel with ageing temperature is small because of the higher amounts of Cu than HSLA-A steel. The fine, round ε-Cu precipitates grow with ageing temperature and finally transform into rod shape.
ScienceON
KISS연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
