Pseudocubic-based polymorphic phase boundary structures and their effect on the piezoelectric properties of (Li,Na,K)(Nb,Sb)O3-SrZrO3 lead-free ceramics

Thermally stable high strain and piezoelectric characteristics of (Li, Na, K)(Nb, Sb)O3‐CaZrO3 ceramics for piezo actuators

“…Furthermore, the pseudocubic samples also exhibit relatively high piezoelectric characteristics, indicating that the pseudocubic phase formed in these samples is the rhombohedral phase rather than the cubic phase. Similar results were found for (Li, Na, K)(Nb, Sb)O 3 ‐SrZrO 3 ceramics …”

“…Therefore, the pseudocubic structure is similar to the rhombohedral structure rather than the pure cubic structure. The E C of the sample with x = 0.0 is large (1.1 kV/mm) and decreases continuously with the increase in x, probably because of the development of the rhombohedral (or pseudocubic) structure; this is because a specimen with the rhombohedral structure generally shows a relatively small E C value . In general, d 33 and k p are proportional to P r × ε T 33 and d 33 × g 33 , respectively.…”

“…The densities of the specimens were measured by using Archimedes’ method. The structural, dielectric, and piezoelectric characteristics of the synthesized samples were analyzed, as described in Data …”

“…NKN materials have a pseudocubic structure near the T C , revealing that the pseudocubic specimen could display a high ε T 33 . The pseudocubic structure is not a cubic structure and is reported to be similar to the rhombohedral structure or a mixture of tetragonal and cubic structures . Moreover, this pseudocubic structure can coexist with the orthorhombic (or tetragonal) structure upon decreasing the T C , resulting in the development of the orthorhombic‐pseudocubic (or tetragonal‐pseudocubic) PPB structures at RT .…”

“…Therefore, it is considered that a specimen having a pseudocubic‐based PPB structure could reveal large d 33 and k p values. Recently, specimens with orthorhombic‐pseudocubic PPB and tetragonal‐pseudocubic structures were reported to display high piezoelectric properties . However, the T C of a specimen with the pseudocubic‐based PPB structure is generally low.…”