• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1273-1274
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• 2006

Chemically pure, hydride/dehydride titanium powders were cold pre-compacted then extruded at $850^{\circ}C$ and $\sim450MPa$ under argon. The extrusions were 100% dense with a narrow band of surface porosity and equiaxed microstructure of similar magnitude to the starting material. The tensile properties of the bars were better than conventionally extruded CP titanium bar product. Outcomes from this study have assisted in the identification of a number of key characteristics important to the extrusion of titanium from pre-compacted CP titanium powders, allowing the elimination of canning and hot isostatic pressing (HIPping) of billets prior to extrusion as per conventional PM processes.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.759-760
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• 2006

Ti-6Al-4V has low specific gravity, high corrosion resistance and superior mechanical properties but it is very difficult to control oxygen content in MIM process. It is necessary to use powders with coarse particle size to decrease oxygen content of powders, so feedstocks with poor fluidity and sintered bodies with lower density are obtained in such cases. Fine titanium hydride-dehydride powders were blended with atomized powders to accomplish higher fluidity and sintered density. Sintered bodies had higher sintered density and mechanical properties equivalent to those of wrought materials by controlling oxygen content less than 0.35mass%.

• 한국분말재료학회지
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• 제16권1호
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• pp.28-32
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• 2009

The activation temperatures and hydrogen sorption rates of $Ti_{80-X}Zr_{20}V_X$ alloys were evaluated at room temperature. The alloy powders were prepared by arc melting and then hydride-dehydride(HDH) process. The alloy powders were apt to activate by increase of vanadium in Ti-Zr-V alloys. The easy activation was explained in terms of surface oxygen content which decreased with increase of vanadium on Ti-Zr-V alloys.

• 한국재료학회지
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• 제10권7호
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• pp.464-470
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• 2000

스폰지 티타늄으로부터 수산호-탈수소화법(HDH)법으로 제조된 부말에 고상탈산법(DOSS)을 적용시켜 만든 산소 농도 범위 1980~8450 ppm, 입경 $25\mu\textrm{m}$ 내외의 불규칙 티타늄 분말의 성형 및 소결성을 조사하였다. 250MPa의 가압력으로 냉간압축성형한 결과, 성형밀도는 69.0%~62.3% 범위 내에 있었고 산호함량 증가에 따라 직선 또는 완만하게 감소하였다. 이러한 경향은 티타늄 분말의 경도변화로 설명할 수 있었다. 최고 7%까지의 차이를 보였던 성형밀도에도 불구하고 $1100^{\circ}C$에서 2시간동안 소결한 결과, 산소함량에 무관하게 소결밀도는 90.5$\pm$0.5%를 보였으며, 결정립의 크기는$60\mu\textrm{m}$ 내외의 균일하였고, 가공크기 및 분포도 유사하였다. 소결체의 경도에 미치는 산소의 영향은 실험범위 내에서 VHN(sintered)=135.5+64.3$\times$(wt%$O_2$)의 실험식을 얻었다. 소결체의 파단면 관찰한 결과, 연성에서 취성파괴로의 천이는 소결체에의 산소함량이 2987~5582ppm 사이에서 일어나는 것으로 나타났다.