• Title/Summary/Keyword: 상변태

Search Result 240, Processing Time 0.024 seconds

"주해상한론(註解傷寒論) 변태양병맥증병치법상제오(辨太陽病脈證幷治法上第五)"에 대(對)한 연구(硏究)

  • Kim, Jin-Ho;Bang, Jeong-Gyun
    • Journal of Korean Medical classics
    • /
    • v.20 no.3
    • /
    • pp.101-120
    • /
    • 2007
  • "주해상한론(註解傷寒論)"시성무이저술적서적(是成無已著述的書籍), 저시관우(這是關于)"상한론(傷寒論)"최초주석적서(最初注釋的書). "주해상한론(註解傷寒論)"유지대영향우후대의가(劉至大影響于後代醫家), 단야유제기관우도식적해석지비판(但也有提起關于圖式的解釋之批判). "주해상한론(註解傷寒論)"시주서술관우태양병개념화계지탕증(是主敍術關于太陽病槪念和桂枝湯證). 특별관우중풍화상한적내용시설명태양병적개념(特別關于中風和傷漢的內容是設明太陽病的槪念), 후대의가근종차설(後代醫家근從此說). 야성무이설명대우계지탕증적병기(也成無已說明對于桂枝湯證的病機), 시이풍상위적개념래설명적(是以風傷衛的槪念來說明的).

  • PDF

Analysis of Heat Treatment Process for Large Forgings Considering Phase Transformation (대형 단조품 담금질 과정의 조직 및 응력분포 해석)

  • 이정호;이부윤;전제영;이명렬;조종래
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1996.11a
    • /
    • pp.964-968
    • /
    • 1996
  • The demands of size and quality of large steel shaft forgings for ship building, power plant, steel plant, etc. are rapidly increasing, and some of these productions are manufactured from ingot weighing more than 300 tons. For use as rotating components. shafts require toughness, strength and homogeneity, and therefore are produced through a variety of heat treatments. According to the increase of ingot size, micro- and macrosegregation and also mass effect of the product increase. Thus, special care should be paid to the heat treatment of such large shaft forgings. In this paper, the heat treatment of large shaft forgings such as rotor and back-up roll is calculated using the commercial finite element code SYSWELD. Calculated distributions of temperature and phase are compared with experimental data. The continuous cooling transformation diagram, thermal and mechanical properites of each phase are used. The phase proportion, hardness and residual stress during water quenching are discussed.

  • PDF

Microstructure Observation of Pd-Cu-Ga system Dental Alloy in Clinical Heat Treatment (치과용 Pd-Cu-Ga 계 함금의 임상조건에 따른 미세조직 관찰)

  • 김기주;이진형
    • Journal of Biomedical Engineering Research
    • /
    • v.20 no.4
    • /
    • pp.443-449
    • /
    • 1999
  • 현재 시판되고 있는 치과용 76.5%Pd-11.6%Cu-7.2^%GarP 합금의 주조상태 및 임상열처리에 따른 미세조직의 변화를 X-선 회절기, 광학현미경, 시차열분석기를 이용하여 관찰하였다. 주조상태, 탈개스 및 세리믹소성처리 후 미세조직은 Pd고용체와 금속간화합물 Pd2Ga으로 구성되어 나타났고, 이들 상들은 열처리에 따라 상당한 변화를 보였다. 또한 Pd은 아르곤 분위기 내의 산소와 반응하여 산화물 형성 및 분해로 인해 질량변화곡선(TG)이 변하였고, 시차열분석(DTA)에서는 약 815$^{\circ}C$ 정도에서 Pd2Ga에 기인하는 흡열피크를 확인하였다. 이러한 실험의 결과들은 Cu가 이원계 Pd-Ga 합금의 Ga의 고용량을 낮추어 공정반응이 저 Ga 쪽으로 이동하기 때문인 것으로 설명하였다. 그러나 앞으로 보다 명확한 상변태 규명을 위해서 TEM등의 분석장비를 사용하여 체계적인 연구가 요구된다.

  • PDF

Tensile Properties of High Mn Austenitic Stainless Steel with Two Phases of Martensite and Austenite (마르텐사이트와 오스테나이트의 2상 조직을 갖는 고 Mn 오스테나이트계 스테인리스강의 인장성질)

  • Kim, Young-Hwa;Kang, Chang-Yong
    • Journal of Ocean Engineering and Technology
    • /
    • v.27 no.4
    • /
    • pp.9-13
    • /
    • 2013
  • The tensile properties of high manganese austenitic stainless steel with the two phase structures of deformation-induced martensite and reversed austenite were studied. Reversed austenite with an ultra-fine grain size of less than $0.3{\mu}m$ was obtained by reversion treatment. The two phases structures of deformation-induced martensite and reversed austenite were obtained by an annealing treatment in the range of $500^{\circ}C-700^{\circ}C$ for various times in 70% cold- rolled high-manganese austenitic stainless steel. The volume fraction of the reversed austenite increased rapidly with increases in the annealing temperature and time. In the stainless steel with the two phases of austenite and martensite, the strength decreased rapidly, while the elongation increased slowly and then rapidly increased with an increase in the volume fraction of the reversed austenite. Therefore, the strength and elongation were strongly controlled by the volume fraction of reversed austenite. A good combination of high strength and elongation could be obtained by the mixed structure of reversed austenite and deformation-induced martensite.

"유문사친(儒門事親)"의 '토법(吐法)'에 관한 연구

  • Kim, Gi-Uk;Park, Hyeon-Guk;Kim, Yong-Ju
    • Journal of Korean Medical classics
    • /
    • v.21 no.2
    • /
    • pp.193-200
    • /
    • 2008
  • 재전통의학이론상일반운용'토법'적주요목표이병인화병위양종분류인식하거적(在전統의학理논上一般운用'吐法'的主要目표以病因和病位양종分류인식下去的). 관우병인의미착직접토출격상(관于病因意味着직接吐出膈上), 위완적담음숙식지인착오적섭식지유독지물(胃脘的痰음宿食지因錯오的섭食之有毒之物), 관우병위가이설(관于病位可以설), '기고자(其高者), 인이월지'적'기고자'시지상완(因而越之'的'其高者'是指上脘), 격상적유형실사(膈上的有形실邪). 장자화재 "유문사친"상설"일토지중(장子和在"儒門事親"上설"一吐之中), 변태무궁(변태无궁), 루용루험(屢用屢험), 이지불의(以지不疑)", 몰구완격담식혹비교고적병위(沒拘脘膈痰食或比較高的病位). 이차통과흔다임상경험(而且通과흔多임床경험), '토법(吐法)'능취득료타개현부이발산피부적청양(能取得了打개玄府而발散皮부的淸양), 타개하초(打개下焦), 천착장중적옹체(穿着腸中的壅滯), 통조수도(通조水道), 단절수지상원(단絶水之上源), 접통울체(接通울滯), 피상행진기(被上行진기), 접통관객(接通관객), 교류상하적(交流上下的) 음양(陰陽), 교제심신(交제心신), 조절병교제수화(조절병交제水火), 창달기기(창달기기), 접통경락혈맥등적성효(接通경絡血맥等的成效). 인차타확장료'토법'적치료범위(因此他擴장了'吐法'的治료范圍). 본논문관우장씨적'토법'(本논文관于장氏的'吐法'), 개념(槪念), 방법급종류(方法及종류), 규율(규律), 통토적치료기전(通吐的治료기전), 금기(禁忌), 조선적방면래진행정리(조宣的方面래진行整理), 보고(報告).

  • PDF

A study on the fabrication of $Pb(Fe^{0.5},Nb^{0.5}O_3$ thin films by a Co-sputtering technique and their characteristics properties (동시 스퍼터링법에 의한$Pb(Fe^{0.5},Nb^{0.5}O_3$박막의 제조 및 특성 평가에 대한 연구)

  • 이상욱;신동석;최인훈
    • Journal of the Korean Vacuum Society
    • /
    • v.7 no.1
    • /
    • pp.17-23
    • /
    • 1998
  • $Pb(Fe_{0.5}Nb_{0.5}O_3(PFN)$ thin films were prepared by rf magnetron co-sputtering method on $SiO_2/Si$, ITO/glass, and $Pt/Ti/SiO_2/Si$ substrates and post-annealed at the $N_2$ atmosphere by RTA(rapid thermal annerling). The degree of crystallinity of PFN films was identified on various substrates. Electrical properties of PFN films was characterized for $Pt/PFN/Pt/Ti/SiO_2/Si$ structure. The composition of PFN films was estimated by EPMA (electron probe micro analysis). PFN films would be crystallized better to perovskite phase on ITO/glass substrate than $SiO_2/Si$ substrate. This may be induced by the deformation of Pb deficient pyrochlore phase due to Pb diffusion into $SiO_2/Si$ substrate. PFN films on $Pt/Ti/SiO_2/Si$ substrate. PFN films with 5-10% Pb excess were crystallized to perovskite phase from $500^{\circ}C$ temperature. In summary, we show that Pb composition and annealing temperature were critically influenced on crystallinity to perovskite phase. When PFN film with 17% Pb excess was annealed at $600^{\circ}C$ at the $N_2$ atmosphere for 300kV/cm and 88. Its remnant polarization coercive field $2.0 MC/cm^2$ and 144kV/cm, respectively.

  • PDF

An Investigation on the Magnetic Properties of Melt-Spun Fe-Pr-C Alloys (Melt-Spun Fe-Pr-C 합금의 자기적 특성 조사)

  • 장태석;조대형
    • Journal of the Korean Magnetics Society
    • /
    • v.7 no.4
    • /
    • pp.173-179
    • /
    • 1997
  • Change in phases, microstructures, and magnetic properties by the variation of quench rate and heat treatment were investigated for melt-spun $Fe_{77}Pr_{15}C_8$ ribbons. The amorphization of as-spun ribbons increased as the quench rate increased. As a result, the ribbon quenched at 40 m/s was almost entirely amorphous. Similarly to cast alloys, the primary phase in crystalline ribbons quenched at 10 m/s was $\alpha$-Fe followed by the secondary $Fe_{17}Pr_2C_x$. Crystalline phases were still dominant in the ribbon spun at 20 m/s, but in this case crystallization of $Fe_{17}Pr_2C_x$ was remarkable with a little suppression of $\alpha$-Fe. At 30 m/s an amorphous phase obviously dominated in the as-spun ribbons with small fraction of crystals. Therefore, substantial amount of hard magnetic $Fe_{14}Pr_2C$ was not obtained from the as-spun state but, as in cast alloys, produced only by a solid-state transformation. Within a few minutes fine grains of $Fe_{14}Pr_2C$ were easily obtained at relatively low temperature when the degree of amorphization of as-spun ribbons was higher. The grain size of $Fe_{14}Pr_2C$ was well less than 1${\mu}{\textrm}{m}$. The ribbons quenched at 20 or 30 m/s yielded higher coercivities after heat treatment.

  • PDF

Phase Transition and Relaxor Behaviors in the Lead Magnesium Niobate-based Ferroelectrics (Pb(Mg1/3Nb2/3)O3-based 강유전체의 상전이 및 완화특성)

  • Kim, Y.J.;Lee, J.H.
    • Journal of the Korean Vacuum Society
    • /
    • v.17 no.2
    • /
    • pp.148-155
    • /
    • 2008
  • Dielectric and pyroelectric properties of relaxor ferroelectric in the PMN-PT solid solution series have been investigated. Features of the diffuse phase transition in PMN-PT system, typical relaxor ferroelectric materials, were studied as a function of temperature and frequency. The transition temperature of the ceramics with PT$\sim$0.325 did not depend on the measuring frequency. This can best realized in a relatively random environment that apparently is provided by PMN-rich complex perovskites, including those containing Pb. The composition with PT>0.35 show the characteristics of a normal single phase ferroelectric material. Thus the studies revealed that the morphotropic phase boundary in the PMN-PT system is in the vicinity of PT$\sim$0.3 and it has a small curvature and as a result the compositions near the morphotropic phase boundary show two phase transitions, rhombohedral$\rightarrow$tetragonal$\rightarrow$cubic, when the samples are heated up to higher temperature. The best optimum compositions are observed near the morphotropic phase boundary.

A Study on the Bainite Phase Control of Direct-Quenched Low Carbon Steels (저탄소 직접 소입강의 베이나이트상 조절에 관한 연구)

  • An, Byeong-Gyu;Go, Yeong-Sang;Lee, Gyeong-Seop
    • Korean Journal of Materials Research
    • /
    • v.6 no.8
    • /
    • pp.841-851
    • /
    • 1996
  • In a recent investigation, the formation of bainite phase in direct-quenched low carbon non heat-treated steel was reported. In this study the effects of bainite phase on the mechanical properties of direct-quenched microalloying steels were investigated. By isothermal transformation at $480^{\circ}C$ for 7 sec., volume fraction of bainite lath was 15~20%, and the UTS and impact energy were increased. In this case $B_{ll}$ and $B_{lll}$ type bainite was observed and the fractography of impact test specimen showed a ductile fracture tendency. Isothermal transformation for 100sec., yielded 30% volume fraction of granular bainite and the mechanical properties were decreased. The f ractography of impact test specimen showed a brittle fracture tendency. The addition of Mo was more effective than B for improving impact energy because amounts of boron aditions were restricted to considerably lower levels, typically 10~ 30ppm. From this study, it is predicted that 15~20% volume fraction of lath bainite on the direct quenching process is procduced by addition of Mo up to 1.2wt. % and controlling the finish forging proc¬ess at $1000^{\circ}C$ and using oil as direct quenching media. This will improve mechanical properties of the direct- quenched steel.

  • PDF

The Variation of Thermal Cycle on the Transformation Temperature and Mechanical Properties of CuZnAi Shape Memory Alloy (CuZnAI형상기억합금의 변태온도에 미치는 열사이클 및 기계적성질 변화)

  • Yang, Gwon-Seung;Park, Jin-Seong;Gang, Jo-Won
    • Korean Journal of Materials Research
    • /
    • v.4 no.5
    • /
    • pp.524-534
    • /
    • 1994
  • The effects of transformation temperature and mechanical properties by thermal cycle of CuZnAl shape memory alloy with a small of misch metal and Zr contents were investigated. The addition of misch metal and Zr was very effective for reducing the grain size. After solution treatment, the specimens were post-quench aged or step quenched at $100^{\circ}C$ to $350^{\circ}C$ for variation of Rockwell hardness value. It was found that the Rockwell hareness value was very increased at $200^{\circ}C$ and $250^{\circ}C$. The fracture strength and ductility have been significantly increased with the increase of misch metal conten when tensile tested below $M_f$ temperature. Also, the fracture strength has been more increased in the case of post quench aging treatment than that of the as-quenching treatment. Aging of the $\beta$-phase decreases the $M_s$ temperature, but that of the martensite phase increases the $A_s$ temperature. The change in $A_s$ temperature with post-quench aging can be attributed to recovery of order in the $\beta$phase. The hystersis of transformation temperature ($A_s-M_s$) has an increasing tendency by thermal cycles.

  • PDF