Bismuth sodium titanate lead‐free piezoelectric coatings by thermal spray process

Abstract

Bismuth sodium titanate (BNT) piezoelectric ceramic coatings with dense morphology and single perovskite phase were fabricated by thermal spray process. The melting and crystallization behaviors of BNT near congruent composition and the effect of excess Bi composition were investigated by analyzing the heating-melting-cooling cycle for the application in thermal spray process. Crystal structure and morphology of the thermal sprayed BNT coatings were examined, and their electrical and electromechanical properties were tested. An effective piezoelectric coefficient d 33 of 50 pm/V was obtained under substrate clamping, measured with laser scanning method. The findings have shed light on the design of appropriate compositions for achieving high quality lead-free piezoelectric ceramic coatings by the scalable thermal spray process.

Structural evolution of thermal sprayed bismuth sodium titanate piezoelectric ceramic coatings

“…The ceramic powder feedstocks and substrates preparation were reported in our previous publication . An Atmospheric Plasma Spraying system (9MC, Sulzer Metco Inc., Westbury, NY) was conducted at ambient pressure using Ar plasma with plasma power of 23 kW.…”

“…As important smart materials, piezoelectric ceramic coatings have shown great application potentials in structure health monitoring, energy harvesting, etc. Research efforts have been reported on fabricating piezoelectric ceramic coatings by thermal spray process . By far, most of the thermal sprayed piezoelectric ceramic coatings had Pb‐based compositions, due to the outstanding electromechanical coupling properties of lead zirconate titanate (PZT) bulk ceramic.…”

“…The understanding on the structural evolution from melt to solid phase during the thermal spray process is important to realize the targeted single crystalline phase and achieve excellent piezoelectric property of the resulting thermal sprayed ceramic coatings. Our recent work on thermal sprayed bismuth sodium titanate (BNT) coating showed promising results of obtaining single perovskite crystalline phase and superior piezoelectric performance properties. However, the understanding on the structural evolution involving the recrystallization behavior from the melt of the thermal sprayed piezoelectric compositions, including BNT system, is insufficient.…”

Potassium sodium niobate (KNN)‐based lead‐free piezoelectric ceramic coatings on steel structure by thermal spray method

“…With the extensive efforts and significant progress on developing lead‐free piezoelectric ceramics with competitive performance properties, they are regarded as the promising candidates to replace the market‐dominant PZT‐based materials for various applications . Recently, our group first reported thermal‐sprayed KNN‐based and bismuth sodium titanate (BNT)‐based lead‐free piezoelectric ceramic coating . The thermal‐sprayed coatings exhibited single phase of perovskite structure and strong piezoelectric response, with effective piezoelectric coefficient (d 33 ) up to 112 pm/V .…”

“…27,28 Recently, our group first reported thermal-sprayed KNN-based and bismuth sodium titanate (BNT)-based lead-free piezoelectric ceramic coating. [29][30][31] The thermal-sprayed coatings exhibited single phase of perovskite structure and strong piezoelectric response, with effective piezoelectric coefficient (d 33 ) up to 112 pm/V. 29,31 The lead-free KNN-based or BNT-based ceramic compositions are environmentally friendly and thus suitable for wide implementation in largearea coating applications.…”