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Sodium Potassium Niobate-Based Piezoelectrics Sintered in Humid Air
Summary
High humidity during sintering of lead-free piezoelectric ceramics like lithium niobate-modified sodium potassium niobate (LKNN) improves density and functional properties. This suggests no special atmosphere control is needed for fabrication, simplifying processing.
Area of Science:
- Materials Science
- Ceramic Engineering
- Solid-State Chemistry
Background:
- Humidity's impact on early processing of lead-free piezoelectric powders is known.
- The effect of humidity during later fabrication stages, like sintering, is less understood.
Purpose of the Study:
- To investigate the influence of humidity on the sintering and functional properties of 0.06LiNbO3-0.94(K0.5Na0.5)NbO3 (LKNN) piezoceramics.
- To determine if humidity control is necessary during the sintering of these lead-free materials.
Main Methods:
- Sintering of LKNN samples in controlled high-humidity air.
- Characterization of density, dielectric losses, and mechanical quality factor.
- Long-term storage and re-evaluation of piezoelectric parameters.
Main Results:
- Samples sintered in high humidity exhibited higher density.
- Lower dielectric losses and an increased mechanical quality factor were observed.
- These improved properties remained stable for at least five months.
Conclusions:
- Sintering lead-free piezoelectric ceramics in high humidity enhances density and functional properties.
- The findings indicate that specialized atmosphere control is not required to prevent adverse humidity effects during LKNN sintering.
- This simplifies the fabrication process for sodium potassium niobate-based piezoceramics.
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