ZrB2 분말의 입도 및 산화도가 치밀화에 미치는 영향
Effects of particle size and oxygen contents on ZrB2 powder for densification
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본 연구에서는 zirconium diboride(ZrB2)의 소결성 향상을 위해 두 가지 전처리 공정을 사용하였다. 물리적 전처리 공정으로 SPEX mill을 사용하여 as-received ZrB2 powder의 입도를 2.61 μm에서 0.35 μm까지 감소시킬 수 있었다. 화학적 전처리 공정으로 희석된 불산 용액을 사용하여 ZrB2 powder의 산화도를 4.20 wt%에서 2.22 wt%까지 감소시킬 수 있었다. 소결된 ZrB2의 상대 밀도는 입도와 산화도가 감소함에 따라 증가하였다. ZrB2의 치밀화에는 산화도 보다 입도의 영향이 더 크다는 것을 확인하였다. 두 가지 전처리 공정을 통해 소결 조제의 사용 없이 치밀한 ZrB2 소결체를 제조하였다. 물리적 화학적 전처리 공정을 사용함으로써 ZrB2의 소결성을 향상시킬 수 있었다.
Abstract
In this study, two pretreatment methods were used to improve the sinterability of zirconium diboride (ZrB2). As a mechanical treatment, as-received ZrB2 powder was crushed using SPEX mill from an average size of 2.61 μm to 0.35 μm. As a chemical treatment, oxygen contents of ZrB2 powder were decreased from 4.20 wt% to 2.22 wt% using a dilute hydrofluoric solution. The relative density of sintered ZrB2 increased with decreasing particle size and oxygen contents. But it is considered that particle size is more effective than oxygen contents for ZrB2 densification. Through the two pretreatment processes, we produced sintered ZrB2 ceramic with a full density without sintering additives. The sinterability of ZrB2 was improved by using mechanical and chemical pretreatment methods.
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