• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1489-1491
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• 1996

The effect of Ag alloy sheath have been investigated in terns of critical current density and mechanical property. Nevertheless the continuous improvement of critical current density($J_c$) of Ag sheathed Bi2223 oxide superconducting wire processed with powder in tube(PIT) method, poor mechanical strength is still considered to be demerits for power application. In this study, we prepared two kinds of Ag- x wt% Cu alloy and pure Ag sheathed Bi2223 superconducting tapes. The hardness and tensile strength of prepared tapes has been measured. Their mechanical propertes were improved by Ag alloying.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.59-65
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• 2003

Four kinds of $Si_3N_4$-based ceramic cutting tools with different sintering time were fabricated to investigante the effect of sintering time on the microstructure, mechanical properties, grain sizes and the cutting performance. An endeavor was also made to determine the relation among mechanical property, Brain size and tool life. $Si_3N_4$ home made cutting tool sintered for 1 hour under $1760^{\circ}$ temperature and 25MPa pressure showed the best cutting performance among selected ceramic tools during machining both Bray cast iron and heat treated SCM440. Multiple linear regression model was used to estimate the tool lift from mechanical property, grain size and showed good result. It was also shown that hardness imposed the biggest offect on tool life.