ZrO2 is a candidate material for hip and knee joint replacements because of its excellent combination of biocompatibility, corrosion resistance and low density. However, the drawback of pure ZrO2 is a low fracture toughness at room temperature. One of the most obvious tactics to cope with this problem is to fabricate a nanostructured composite material. Nanomaterials can be produced with improved mechanical properties(hardness and fracture toughness). The high-frequency induction heated sintering method takes advantage of simultaneously applying induced current and mechanical pressure during sintering. As a result, nanostructured materials can be achieved within very short time. In this study, W and ZrO2 nanopowders are mechanochemically synthesized from WO3 and Zr powders according to the reaction(WO3 + 3/2 Zr→W+ 3/2 ZrO2). The milled powders are then sintered using high-frequency induction heating within two minutes under the uniaxial pressure of 80MPa. The average fracture toughness and hardness of the nanostructured W-3/2 ZrO2 composite sintered at 1300oC are 540 kg/mm2 and 5 MPa·m1/2, respectively. The fracture toughness of the composite is higher than that of monolithic ZrO2. The phase and microstructure of the composite is also investigated by XRD and FE-SEM.

Abstract
 1. 서 론
 2. 실험 방법
 3. 결과 및 고찰
  3.1 나노분말 합성
  3.2 나노분말 소결
  3.3 기계적 특성
 4. 결 론
 References

• 김성은(전북대학교 신소재공학부 수소연료전지 연구센터) | Seong-Eun Kim (Division of Advanced Materials Engineering, the Research Center of Hydrogen Fuel Cell, Chonbuk National University)
• 손인진(전북대학교 신소재공학부 수소연료전지 연구센터) | In-Jin Shon (Division of Advanced Materials Engineering, the Research Center of Hydrogen Fuel Cell, Chonbuk National University) Corresponding author