http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Si-Cr 스프링 강에서의 Mo 및 W 첨가가 미세조직 및 기계적 성질에 미치는 영향
남원종,이상래,반덕영 대한금속재료학회(대한금속학회) 1998 대한금속·재료학회지 Vol.36 No.2
Effects of the Mo and W additions to Si-Cr spring steels on the microstructural evolution and mechanical properties in spring steels were investigated. It was found that the Mo and/or W addition does not change the behavior of tempered carbide at low temperatures, such as the precipitation of ε-carbide and the conversion of ε-carbide to cementite, via dilatometry tests and the observation of microstructure using TEM. However, it would reduce the coarsening rate of cementite at high temperatures above 450℃, resulting in the smaller size of cementite particles due to the lower diffusion rate. Since the sag resistance depends on the distribution and the size of precipitates, steel C(0.2% W) showed the strongest sag resistance whereas steel A showed the weakest sag resistance, when tempered at 450℃. Also, an abundance of precipitates at 350℃ tempering exhibits the maximum loop area, i.e., the sag resistance for all the tested steels. The Mo and W additions to Si-Cr spring steels raised the ratio of loop area/tensile strength. Therefore, the Mo and W additions would be effective method to increase the sag resistance as well as strength in Si-Cr spring steels.
남원종,최해창 대한금속재료학회(대한금속학회) 1998 대한금속·재료학회지 Vol.36 No.2
The effects of the alloy content of Si, Ni and V and tempering temperatures on mechanical properties, especially hardness and yield strength, of 0.6C-(1.0-2.5)Si-(0.7-1.8)Ni-(0.1-0.2)V steels were investigated by hardness tests, tensile tests and transmission electron microscopy. The results showed that tempering temperatures for the maximum yield strength and the softening resistance in hardness moved to higher temperatures due to the retardation of the conversion of ε-carbide to cementite within martensite laths by Si addition. Additionally, it was found that the temperatures of the conversion of ε-carbide to cementite was not changed by the addition of Ni or V addition in present steels. The contribution of Ni or V addition was limited only to the increase in hardness and yield strength.