http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
[論文] STS 420 스테인레스 강의 기계적 성질 및 피로균열전파에 미치는 템퍼링 온도의 영향
박용식(Y.S.Park),임병수(B.S.Lim) 한국자동차공학회 1992 오토저널 Vol.14 No.4
An experimental investigation has been carried out to determine the effect of tempering temperature on the fatigue crack propagation behavior and mechanical properties using the quenched and tempered STS420 martensitic stainless steel.<br/> Heat treatments of tempering for two hours at the five different temperatures of 150℃, 300℃, 450℃, 600℃ and 700℃ have been performed on the martensite obtained by air cooling the specimens austenitized for one hour at 1010℃. Tensile strength, yield strength, hardness, ?K_th. C and m values of differently tempered specimens have been investigated by tensile, hardness and fatigue tests.
SNCM220 강 권축의 침탄 열처리를 통한 피로 강도 개선에 관한 연구
이호성(H. S. Lee),임병수(B. S. Lim) 한국자동차공학회 1996 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1996 No.11_1
To find out the reason of fracture, specimens were made from the fractured winding shaft and the mechanical properties as well as their microstructures were investigated. Several heat treatments, including caburizing and tempering, were carried out to improve the microstructure, mechanical properties and rotating bending fatigue characteristics. Through these experiments, following conclusions were obtained, (1) Carburized and tempered specimens showed greatly improved mechanical properties including impact energy, hardness and strength. (2) The fatigue strength of the carburized and tempered specimens increased more than twice than that of the original fractured winding shaft.<br/>
[論文] SM45C강의 피로 균열 성장에 미치는 미세조직의 영향
김현철(H. C. Kim),임병수(B. S. Lim) 한국자동차공학회 1991 오토저널 Vol.13 No.2
To determine the effects of microstructure on the fatigue crack propagation behavior in SM45C steel, experimental investigations have been carried out with the specimens of different grain sizes and different spacings between the Fe₃C particles. Fatigue and tensile tests were conducted and the quantitative analysis of the relations between the threshold stress intensity range and grain size, interparticle spacing and yield stress were carried out. Some of the conclusions obtained are as fallows; (1) △Kth was observed to increase with grain size and the spacing between the Fe₃C particles. (2) In both pearlite and spheroidite microstructures, △Kth was increased when yield stress was decreased.
Ti-3Al-2.5V 합금의 고온피로에 미치는 온도 및 미세조직의 영향
김현철(H. C. Kim),임병수(B. S. Lim) 한국자동차공학회 1998 한국 자동차공학회논문집 Vol.6 No.3
To detennine the effect of temperature and microstructure on the fatigue crack propagation behavior in Ti-3Al-2.5V alloy, experimental investigations have been carried out with the specimens of different temperatures and different volume fractions of prime<br/> a -phase. The temperatures employed were room temperature, 200°C, 300°C and 400°C under the same frequency of 20Hz. To obtain the different volume fractions of the primary a -phase, specimens were solution - treated at a + i3 and above the i3 region.<br/> From the experimental results, following conclusions were obtained. (1) L1 Kth was observed to increase with the less volume fraction of the primary a -phase. (2) As the temperature increased the da/dN became greater while the material constant, m, decreased as temperature increased. (3) Microstructures having more primary a -phase showed higher strength at the high temperatures.<br/>
Ti-6A1-4V 합금의 피로거동에 미치는 온도 , 주파수 및 미세조직의 영향
김현철(H. C. Kim),김승한(S. H. Kim),임병수(B. S. Lim),김두현(D. H. Kim),이용태(Y. T. Lee) 한국자동차공학회 1996 한국 자동차공학회논문집 Vol.4 No.1
The effect of temperature, frequency and microstructure on fatigue crack propagation property of Ti-6Al-4V alloy has been investigated. Teh temperatures employed were room temperature, 200°C and 400°C. The frequencies were 20Hz and 8Hz. The microstructures tested were equiaxed and bimodal microstructures. Mechanical properties and fatigue crack growth rates were measured in different test conditions. From the experimental results, following conclusions were obtained.1) Bimodal microstructure showed superior fatigue crack growth resistance to equiaxed microstructure.2) Under all test conditions, fatigue crack growth rate increased with test temperature.3) Wine the frequency decreasing from 20Hz to 8Hz, fatigue crack growth rate increased.
진공침탄한 SCM 415 강의 기계적 성질에 관한 연구
김대욱(D.W.Kim),이영제(Y.Z.Lee),임병수(B.S.Lim) 한국자동차공학회 1998 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1998 No.5_2
High cycle fatigue and dry wear characteristics of vaccum carburized low alloy steel, SCM415(0.149% C), were evaluated after various heat treatments including direct quenching, single reheat quenching and sub-zero treatment. Comparing the fatigue and wear characteristics of carburized specimens to those of hot annealed of reheat quenched specimens, the wear resistant property as well as bending fatigue limits of vacuum carburized steels were substantially superior to other heat treated steels. Test results indicated that the carburized and reheat treated specimens have higher fatigue limits than the carburized and direct-quenched specimens and the specimens followed by sub-zero treatment. The wear wolumes of sub-zero treated specimens with higher surface hardness show slightly lower values than those of non sub-zero treated specimens. This is attributed to the reduction of retained austenite amount of the surface and an increase of surface hardness by the sub-zero treatment effect.<br/>