{
  "spore": "profile",
  "id": "lead-titanate-pzt",
  "spore_version": "0.2",
  "family": "oxide-ceramics",
  "name": "Lead zirconate titanate",
  "abbreviation": "PZT",
  "role": "piezoelectric ceramic (lead zirconate titanate solid solution, Pb(Zr,Ti)O3)",
  "category": "ceramics",
  "type": "oxides",
  "summary": "PZT is a lead zirconate titanate solid solution, a perovskite oxide ceramic. It turns stress into voltage and voltage into motion, and it has been the most widely used commercial piezoelectric material for about 60 years (Seshadri et al., 2018). PI Ceramic's hard grade PIC 255 has a Curie temperature of 350 degC and a charge coefficient d33 of 400 pC/N. A 2 at% Sm-doped laboratory composition near its Curie point reached 915 pm/V, about twice the value of Nb or La donor dopants. The main drawback is lead: the supplier safety data sheet classifies the powder as a reproductive toxicant.\n",
  "best_for": "Transducers and actuators that need a large piezoelectric response well below the Curie point, where lead content is acceptable",
  "weakest_at": "Lead content: the supplier SDS classes the powder as a reproductive toxicant, and PI limits operation to 50 % of the Curie temperature",
  "identity": {
    "formula": "Pb(Zr0.52Ti0.48)O3",
    "cas": "12626-81-2",
    "crystal_system": "perovskite; tetragonal ferroelectric phase below the Curie point (P4mm at 250 degC in the Sm-doped 50:50 study)",
    "space_group": "P4mm",
    "designations": [
      {
        "system": "Trade name",
        "code": "PIC 255",
        "note": "hard PZT, printed in a column shared with PIC 252",
        "source": "pi-pzt",
        "where": "Standard Piezoelectric Material Data, column PIC255/PIC252"
      }
    ],
    "source": "seshadri2018",
    "where": "Introduction (Zr:Ti 52:48 at the morphotropic phase boundary) and Table 1 (P4mm at 250 degC); CAS number from the Stanford Advanced Materials SDS, section 1"
  },
  "tags": {
    "environments": [],
    "stresses": [
      "extreme-heat"
    ],
    "applications": [
      "mechanisms",
      "electronics-and-chips"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density, PIC 255 hard PZT",
      "value": 7.8,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "note": "ceramic density as printed by the maker; not a powder value"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Physical and dielectric properties, Density row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "curie_temperature",
      "label": "Curie temperature, PIC 255 hard PZT",
      "value": 350,
      "bound": "exact",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Physical and dielectric properties, Curie temperature row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "curie_temperature",
      "label": "Curie temperature, Sonox P4 hard PZT (CeramTec)",
      "value": 325,
      "bound": "exact",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "grade": "Sonox P4 (CeramTec Navy Type I hard PZT); a different grade from PIC 255"
      },
      "method": "Value printed in the CeramTec piezoceramic hard materials datasheet",
      "status": "ground",
      "source": "ceramtec-hard",
      "where": "Material characteristics table, Curie temperature Tc row, Sonox P4 column",
      "source_detail": {
        "title": "CeramTec: Piezoceramic Hard Materials (Sonox P4, PZT401, PZT406, Sonox P8, PZT807)",
        "id": "CA220108/EN/2604/IM",
        "url": "https://ceramtec-group.com/fileadmin/user_upload/Corporate/11_Downloads/04_Piezo_Ceramics/CeramTec_Datasheet_Piezo_Hard_Materials_EN.PDF",
        "year": 2026,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "dielectric_constant",
      "label": "Relative permittivity in the polarisation direction, PIC 255",
      "value": 1800,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "quantity": "eps33T/eps0, measured at 23 degC after polarisation"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Relative permittivity row (in polarisation direction)",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "dielectric_constant",
      "label": "Relative permittivity in the polarisation direction, Sonox P4 (CeramTec)",
      "value": 1300,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "grade": "Sonox P4",
        "quantity": "e33T/e0 (free dielectric constant)"
      },
      "method": "Value printed in the CeramTec piezoceramic hard materials datasheet",
      "status": "ground",
      "source": "ceramtec-hard",
      "where": "Dielectric properties table, relative permittivity e33T/e0, Sonox P4 column",
      "source_detail": {
        "title": "CeramTec: Piezoceramic Hard Materials (Sonox P4, PZT401, PZT406, Sonox P8, PZT807)",
        "id": "CA220108/EN/2604/IM",
        "url": "https://ceramtec-group.com/fileadmin/user_upload/Corporate/11_Downloads/04_Piezo_Ceramics/CeramTec_Datasheet_Piezo_Hard_Materials_EN.PDF",
        "year": 2026,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "dissipation_factor",
      "label": "Dielectric loss factor, PIC 255",
      "value": 20,
      "bound": "exact",
      "unit": "10^-3",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "note": "printed as 10^-3 in the source, so 20 means 0.020"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Dielectric loss factor tan delta row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "piezoelectric_d33",
      "label": "Piezoelectric charge coefficient d33, PIC 255",
      "value": 400,
      "bound": "exact",
      "unit": "10^-12 C/N",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "test": "test pieces to EN 50324-2, values 24 h to 48 h after polarisation at 23 degC"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Piezoelectric charge coefficient d33 row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "piezoelectric_d33",
      "label": "Piezoelectric charge coefficient d33, Sonox P4 (CeramTec)",
      "value": 310,
      "bound": "exact",
      "unit": "10^-12 C/N",
      "scope": "material",
      "conditions": {
        "grade": "Sonox P4"
      },
      "method": "Value printed in the CeramTec piezoceramic hard materials datasheet",
      "status": "ground",
      "source": "ceramtec-hard",
      "where": "Electromechanical properties table, charge constant d33, Sonox P4 column",
      "source_detail": {
        "title": "CeramTec: Piezoceramic Hard Materials (Sonox P4, PZT401, PZT406, Sonox P8, PZT807)",
        "id": "CA220108/EN/2604/IM",
        "url": "https://ceramtec-group.com/fileadmin/user_upload/Corporate/11_Downloads/04_Piezo_Ceramics/CeramTec_Datasheet_Piezo_Hard_Materials_EN.PDF",
        "year": 2026,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "piezoelectric_d33",
      "label": "Peak d33 of a 2 at% Sm-doped PZT 50:50 sample near the Curie point (first thermal cycle)",
      "value": 915,
      "bound": "exact",
      "unit": "pm/V",
      "scope": "material",
      "conditions": {
        "composition": "Pb0.97Sm0.02Zr0.5Ti0.5O3, laboratory sample, not a commercial grade",
        "temperature": "near the Curie point, first thermal cycle",
        "measurement": "converse longitudinal piezoelectric coefficient"
      },
      "method": "Peak value reported by the authors for a laboratory sample",
      "status": "ground",
      "note": "A lab result for one doped composition at high temperature, not a rating for PZT in service. After repoling and thermal cycling the same sample reached 583 and then 438 pm/V (see corrosion).",
      "source": "seshadri2018",
      "where": "Abstract; Results, Fig. 1 and Fig. 2 text",
      "source_detail": {
        "title": "Unexpectedly high piezoelectricity of Sm-doped lead zirconate titanate in the Curie point region",
        "id": "doi:10.1038/s41598-018-22566-5 (Sci Rep 8, 4120, PMC5841290)",
        "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC5841290/",
        "year": 2018,
        "kind": "paper",
        "license": "open access, Creative Commons (as listed by PMC)"
      }
    },
    {
      "benchmark": "coupling_factor_kp",
      "label": "Planar coupling factor kp, PIC 255",
      "value": 0.62,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Coupling factor kp row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "mechanical_quality_factor",
      "label": "Mechanical quality factor Qm, PIC 255",
      "value": 80,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "note": "low Qm means high damping of resonance, which suits pulse-mode transducers"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Mechanical quality factor row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "coercive_field_strength",
      "label": "Coercive field strength, PIC 255",
      "value": 1.5,
      "bound": "exact",
      "unit": "kV/mm",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "temperature": "25 degC"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Coercive field strength row (at 25 degC)",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "static_compressive_strength",
      "label": "Static compressive strength, PZT ceramics (PI)",
      "value": 600,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "basis": "PI gives one figure for its PZT ceramics as a group, shown as more than 600 MPa; not a per-grade value"
      },
      "method": "Value printed in the PI Ceramic standard material data table, note on compressive strength",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, note 'Static compressive strength' (right-hand column)",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "speed_of_sound",
      "label": "Speed of sound, longitudinal (v1E), PIC 255",
      "value": 2840,
      "bound": "exact",
      "unit": "m/s",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "wave": "thin-rod longitudinal wave (v1E)"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Speed of sound v1E row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "acoustic_impedance",
      "label": "Acoustic impedance, pressure wave along polarisation, PIC 255",
      "value": 34.7,
      "bound": "exact",
      "unit": "MRayl",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "direction": "polarisation direction"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Acoustic impedance Z33 row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion along polarisation, all PZT (PI approximation)",
      "value": -6,
      "value_high": -4,
      "bound": "range",
      "unit": "10^-6/K",
      "scope": "material",
      "conditions": {
        "basis": "PI approximation stated as valid for all PZT materials, shorted electrodes, polarisation direction",
        "note": "negative: the material shrinks slightly as it heats along the polarisation axis"
      },
      "method": "Approximation printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, notes at right, coefficient of thermal expansion alpha3",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "temperature_coefficient_permittivity",
      "label": "Temperature coefficient of permittivity eps33, PIC 255",
      "value": 3,
      "bound": "exact",
      "unit": "10^-3/K",
      "scope": "material",
      "conditions": {
        "grade": "PIC 255 (column PIC255/PIC252)",
        "range": "-20 to +125 degC"
      },
      "method": "Value printed in the PI Ceramic standard material data table",
      "status": "ground",
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, Temperature coefficient of eps33T row",
      "source_detail": {
        "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
        "id": "PI Ceramic GmbH, revision 08/2024",
        "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
        "year": 2024,
        "kind": "datasheet",
        "license": "manufacturer datasheet, cited not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Thermal cycling to the depoling temperature (laboratory Sm-doped sample, not a commercial grade)",
      "headline": "Heating a doped PZT sample to its depoling temperature and repoling it cut its peak d33 by more than half over three cycles.",
      "effect": "Peak d33 fell from 915 pm/V on the first thermal cycle to 583 pm/V on the second and 438 pm/V on the third. The authors say the sample was not annealed to processing temperature between cycles, so it would not regain full properties, and they suggest changes in phase fraction, domain walls or point defects.",
      "rating": "moderate",
      "conditions": {
        "composition": "Pb0.97Sm0.02Zr0.5Ti0.5O3",
        "cycling": "heat to depoling temperature, then repole to saturation at room temperature, three times"
      },
      "source": "seshadri2018",
      "where": "Results, Fig. 2 and the paragraph after it"
    },
    {
      "environment": "Continuous operation at elevated temperature (commercial PZT ceramics)",
      "headline": "PI recommends operation only up to half the Curie temperature, and gives no ageing rate at that limit.",
      "effect": "PI's standard material data table recommends an operating temperature of up to 50 % of the Curie temperature for PZT. The same table gives no time-dependent drift figure for the grades shown, so the long-term loss of response is not quantified here. Published PZT ageing studies that were found could not be opened in this run (see gaps).",
      "rating": "unknown",
      "conditions": {
        "basis": "manufacturer recommendation for PZT generally, not a test result"
      },
      "source": "pi-pzt",
      "where": "Standard Piezoelectric Material Data, note 'Recommended operating temperature' (right-hand column)"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Supplier SDS (Stanford Advanced Materials, Nov 2022) classifies lead zirconate titanate under Regulation (EC) No 1272/2008 as Repr. 1A (H360: may damage fertility or the unborn child), STOT RE 2 (H373: damage to the reproductive system, blood, brain and endocrine system through prolonged or repeated exposure), and Acute Tox. 4 (H302 and H332: harmful if swallowed or inhaled). Signal word Danger.",
        "ghs": [
          "H360",
          "H373",
          "H302",
          "H332"
        ],
        "source": "stanford-pzt-sds",
        "where": "Section 2 (classification and label elements)"
      },
      {
        "text": "Occupational limits in the same SDS: 0.05 mg/m3 as Pb (US PEL and TLV, 29 CFR 1910.1025) and a biological limit of 30 ug per 100 ml of blood lead.",
        "ghs": [],
        "source": "stanford-pzt-sds",
        "where": "Section 8 (control parameters)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Operation above the recommended temperature limit",
        "trigger": "Use above 50 % of the Curie temperature (350 degC for PIC 255, so above about 175 degC)",
        "consequence": "PI recommends operation up to 50 % of the Curie temperature. The datasheet does not give a response figure above that limit, so the size of the risk is not quantified in this profile.",
        "severity": "moderate",
        "source": "pi-pzt",
        "where": "Standard Piezoelectric Material Data, note 'Recommended operating temperature'"
      },
      {
        "mode": "Loss of piezoelectric response after thermal cycling",
        "trigger": "Heating a 2 at% Sm-doped PZT 50:50 sample to its depoling temperature and repoling it, three times, without annealing",
        "consequence": "Peak d33 fell from 915 to 583 to 438 pm/V over three cycles, so the first-cycle peak was not repeatable.",
        "severity": "moderate",
        "source": "seshadri2018",
        "where": "Results, Fig. 2"
      },
      {
        "mode": "Fire releases lead fume",
        "trigger": "The product is involved in a fire",
        "consequence": "The SDS lists lead oxide fume, zirconium oxide and titanium oxides as products of a fire, and says firefighters should wear a self-contained respirator and a fully protective impervious suit.",
        "severity": "high",
        "source": "stanford-pzt-sds",
        "where": "Section 5 (firefighting measures) and Section 10 (hazardous decomposition products)"
      }
    ],
    "side_effects": [
      {
        "text": "The SDS says not to let the product reach drains, sewage systems or watercourses, and to dispose of waste material under local, regional and national rules.",
        "affects": "Water and soil at the disposal site",
        "source": "stanford-pzt-sds",
        "where": "Section 6 (environmental precautions) and Section 2 (precautionary statement P501)"
      }
    ],
    "handling": [
      {
        "text": "Keep the container tightly sealed in a cool, dry place with good ventilation, and open it with care. Use a chemical fume hood for dust-generating work (average face velocity at least 100 feet per minute, per the SDS).",
        "source": "stanford-pzt-sds",
        "where": "Sections 7 and 8"
      },
      {
        "text": "The SDS says the product is for use only by technically qualified individuals.",
        "source": "stanford-pzt-sds",
        "where": "Section 15 (regulatory information)"
      }
    ],
    "mitigations": [
      {
        "text": "Keep the operating temperature at or below 50 % of the Curie temperature, as PI recommends for PZT.",
        "source": "pi-pzt",
        "where": "Standard Piezoelectric Material Data, note 'Recommended operating temperature'"
      }
    ]
  },
  "uses": [
    {
      "application": "mechanisms",
      "device": "Multilayer piezoelectric stack actuators for spacecraft mechanisms (ground characterisation, not flown)",
      "example": "NASA characterised co-fired multilayer piezoelectric stacks under AC and DC drive at nominal and high temperatures and voltages. Five actuators were driven sinusoidally for up to ten billion cycles. The abstract reports measurements of displacement, impedance, capacitance and leakage current to assess degradation, but gives no degradation result.",
      "source": "nasa-stacks-2008",
      "where": "Abstract (NTRS record 20110013164)"
    },
    {
      "application": "electronics-and-chips",
      "device": "Transducers and sensors for ultrasonic and other electroacoustic systems",
      "example": "The 2018 Scientific Reports paper calls PZT the most commonly used commercial piezoelectric material for the last 60 years and says it is extensively used in the transducer industry because of its electromechanical sensitivity.",
      "source": "seshadri2018",
      "where": "Introduction, first paragraph"
    }
  ],
  "supply": [
    {
      "subject": "Lead",
      "producers": [
        {
          "country": "China",
          "share_percent": 42.2,
          "year": 2025
        },
        {
          "country": "Australia",
          "share_percent": 10.7,
          "year": 2025
        },
        {
          "country": "Peru",
          "share_percent": 6.4,
          "year": 2025
        },
        {
          "country": "United States",
          "share_percent": 6.2,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 Final List of Critical Minerals (lead added in 2025)",
          "listed": true
        }
      ],
      "recycling": "USGS: about 1 million tons of secondary lead was produced in 2025, equal to 70 % of apparent U.S. consumption, nearly all from old scrap, mostly lead-acid batteries.",
      "substitutes": [
        "USGS: the electronics industry has moved toward lead-free solders. The chapter does not discuss lead in piezoelectric ceramics; lead-free piezo grades are not yet approved for production (see story)."
      ],
      "source": "usgs-mcs2026-lead",
      "where": "World Mine Production and Reserves table, 2025e (shares calculated by Space Mushroom against the printed world total of 4,500 thousand t, which is rounded); Events, Trends and Issues (critical list); Recycling; Substitutes"
    },
    {
      "subject": "Zirconium",
      "producers": [
        {
          "country": "Australia",
          "share_percent": 33.3,
          "year": 2025
        },
        {
          "country": "South Africa",
          "share_percent": 22.5,
          "year": 2025
        },
        {
          "country": "Mozambique",
          "share_percent": 13.3,
          "year": 2025
        },
        {
          "country": "Senegal",
          "share_percent": 5.8,
          "year": 2025
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: companies in Oregon and Utah recycled zirconium from new scrap generated during metal production.",
      "substitutes": [
        "USGS: chromite and olivine can substitute for zircon in some foundry applications (not for PZT)."
      ],
      "source": "usgs-mcs2026-zirconium",
      "where": "Zirconium mineral concentrates, mine production table, 2025 (gross weight; shares calculated by Space Mushroom against the printed world total of 1,200 thousand t, which is rounded); Recycling; Substitutes"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables, revision 08/2024)",
      "type": "datasheet",
      "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
      "year": 2024
    },
    {
      "title": "CeramTec: Piezoceramic Hard Materials datasheet (CA220108/EN/2604/IM)",
      "type": "datasheet",
      "url": "https://ceramtec-group.com/fileadmin/user_upload/Corporate/11_Downloads/04_Piezo_Ceramics/CeramTec_Datasheet_Piezo_Hard_Materials_EN.PDF",
      "year": 2026
    },
    {
      "title": "Stanford Advanced Materials: Safety Data Sheet, PZT (lead zirconate titanate), CAS 12626-81-2",
      "type": "sds",
      "url": "https://samaterials.com/tds/1697120751-1966-lead-zirconate-titanate-powder-sds.pdf",
      "year": 2022
    },
    {
      "title": "Unexpectedly high piezoelectricity of Sm-doped lead zirconate titanate in the Curie point region (open access)",
      "type": "paper",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC5841290/",
      "year": 2018
    },
    {
      "title": "Characterization of Piezoelectric Stacks for Space Applications (NASA NTRS 20110013164)",
      "type": "report",
      "url": "https://ntrs.nasa.gov/citations/20110013164",
      "year": 2008
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Lead",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-lead.pdf",
      "year": 2026
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Zirconium and Hafnium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-zirconium-hafnium.pdf",
      "year": 2026
    }
  ],
  "gaps": [
    "No flight, vacuum, radiation or thermal-vacuum result for PZT was found. The only space source is a 2008 NASA ground characterisation of multilayer stacks, whose abstract reports no degradation result.",
    "The 2017 aging studies of soft and hard PZT (Promsawat et al., Ceramics International) and the related Fe-doped PZT study could not be read: the publisher and the repository returned access blocks. No ageing-rate figure from them is included.",
    "No humidity, electrolyte or moisture-exposure result for bulk PZT was found in a source we could open. Thin-film humidity studies were found but not read in full, so they are not used.",
    "Melting point, density and decomposition temperature are 'No data available' in the supplier SDS. The density given is the PI Ceramic figure for PIC 255, not a powder value.",
    "Lead content of a typical commercial PZT (weight per cent) is not stated in the SDS we read. A supplier formulation with PbO at 60 to 70 % was seen in another SDS, but it was not read in full and is not used.",
    "Lead's EU critical raw materials status was not checked, and the zirconium critical-list status was not checked. Titanium supply is not included; see the titanium profiles.",
    "RoHS: Directive (EU) 2025/2363 sets exemption 7(c)-I for lead in piezoelectronic devices to expire on 30 June 2027, per the TUV summary. The official EUR-Lex text and the start date were not read.",
    "Property names not in property-canon.yaml were written in snake_case: piezoelectric_d33, coupling_factor_kp, mechanical_quality_factor, coercive_field_strength, speed_of_sound, acoustic_impedance, static_compressive_strength, temperature_coefficient_permittivity.",
    "Lead-free comparison: PI's lead-free table gives PIC 753 (KNN) a d33 of 241 pC/N with a Curie temperature of 300 degC, marked preliminary and not approved for production. It is noted in the story but not entered as a property, because it is a different material.",
    "No image was sourced for this profile, so media is empty.",
    "Atomic weights in the recipe (Pb 207.2, Zr 91.222, Ti 47.867, O 15.999) are the IUPAC abridged values printed in the Wikipedia element infoboxes read in this run. PubChem element pages returned a browser check, so they were not used.",
    "The RoHS expiry (30 June 2027) comes from the TUV Rheinland summary of Directive (EU) 2025/2363 (source key tuv-rohs-2025). The start date and the official text were not read."
  ],
  "story": {
    "why": "PZT is the workhorse of piezoelectric ceramics. It converts a mechanical strain into a voltage and back again, and it has done so in transducers and actuators for about 60 years (Seshadri et al., 2018). Its response is largest near the morphotropic phase boundary, around 52:48 zirconium to titanium, where high piezoelectric properties are obtained. Its drawback is lead, which makes the powder a reproductive toxicant on the supplier's safety data sheet, and which is the reason RoHS needs a special exemption for piezoelectric devices.",
    "uses": [
      {
        "where": "Multilayer actuators for spacecraft mechanisms",
        "line": "NASA characterised co-fired multilayer PZT stacks under AC and DC drive at nominal and high temperatures. Five actuators were driven sinusoidally for up to ten billion cycles. The abstract reports no degradation result, so it is a test programme, not a lifetime figure."
      },
      {
        "where": "Transducers in the electroacoustic industry",
        "line": "The 2018 paper describes PZT as the most commonly used commercial piezoelectric material for about 60 years and as extensively used in the transducer industry."
      }
    ],
    "can_do": [
      {
        "label": "Piezoelectric response",
        "line": "PI's hard grade PIC 255 has a charge coefficient d33 of 400 pC/N. Sonox P4 from CeramTec gives 310 pC/N. In a laboratory Sm-doped composition, the peak near the Curie point reached 915 pm/V on the first thermal cycle.",
        "benchmark": "piezoelectric_d33",
        "scope": "material",
        "value": "400 pC/N"
      },
      {
        "label": "Temperature limit",
        "line": "PIC 255 has a Curie temperature of 350 degC and Sonox P4 of 325 degC. Above that point the crystal changes from the ferroelectric tetragonal phase to a paraelectric cubic phase, as Seshadri et al. describe. PI's recommended operating limit is half the Curie temperature.",
        "benchmark": "curie_temperature",
        "scope": "material",
        "value": "350 degC"
      },
      {
        "label": "Resonance damping",
        "line": "PIC 255 has a mechanical quality factor Qm of 80, which is low, meaning the resonance is well damped. PI describes the family as suited to pulse-mode transducers.",
        "benchmark": "mechanical_quality_factor",
        "scope": "material",
        "value": "Qm 80"
      },
      {
        "label": "Density and sound speed",
        "line": "PIC 255 has a density of 7.8 g/cm3 and a longitudinal sound speed of 2840 m/s. Its acoustic impedance is 34.7 MRayl.",
        "benchmark": "density",
        "scope": "material",
        "value": "7.8 g/cm3"
      }
    ],
    "compare": "PZT's main cost is lead. The supplier SDS makes the powder a reproductive toxicant, and the EU's RoHS directive keeps a time-limited exemption for lead in piezoelectric devices. PI Ceramic's lead-free KNN grade PIC 753 gives a d33 of 241 pC/N with a Curie temperature of 300 degC, but PI marks those figures preliminary and says the material is not yet approved for production. The compare rows below use PIC 255 and Sonox P4 as the PZT values.",
    "compare_rows": [
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Curie temperature",
        "benchmark": "curie_temperature",
        "scope": "material"
      },
      {
        "label": "Piezoelectric d33",
        "benchmark": "piezoelectric_d33",
        "scope": "material"
      }
    ],
    "handling": [
      "Treat the powder as lead: the SDS classes it as a reproductive toxicant and as harmful by inhalation.",
      "Keep it sealed and dry, and use a fume hood for any work that makes dust.",
      "Keep operating temperature to half the Curie temperature or less, as PI recommends.",
      "In a fire it can release lead oxide fume, so firefighters need a self-contained respirator."
    ],
    "good_for": [
      "Large, stable piezoelectric response: PIC 255 has a d33 of 400 pC/N, with a coupling factor kp of 0.62.",
      "Long track record: PZT has been the most widely used commercial piezoelectric material for about 60 years."
    ],
    "watch_out": [
      "Lead content: the powder is classed as a reproductive toxicant and as a source of lead fume in a fire.",
      "Ageing and thermal history: a laboratory sample lost more than half its peak d33 over three thermal cycles without annealing.",
      "RoHS: the exemption for lead in piezoelectric devices is time-limited, and the TUV summary gives 30 June 2027 as its expiry."
    ],
    "verdict": "PZT gives the strongest piezoelectric response of the materials in this collection's datasheets, but its lead content is a hazard and a regulatory limit. The lead-free grades PI lists are not yet approved for production, so PZT remains the practical choice for now.",
    "recipe": {
      "line": "PZT is a solid solution of lead zirconate and lead titanate with the perovskite structure, written Pb(Zr,Ti)O3. The composition used for high piezoelectric response sits at the morphotropic phase boundary, near 52 mol% zirconium to 48 mol% titanium, written Pb(Zr0.52Ti0.48)O3.",
      "parts": [
        {
          "name": "Lead",
          "symbol": "Pb",
          "role": "The A-site cation. Lead is the element that carries the toxicity of the material. Samarium is substituted for it in the laboratory donor-doped studies.",
          "atoms": 1,
          "atomic_weight": 207.2
        },
        {
          "name": "Zirconium",
          "symbol": "Zr",
          "role": "A B-site cation. Mixing zirconium with titanium near 52:48 gives the morphotropic phase boundary, where high piezoelectric properties are obtained.",
          "atoms": 0.52,
          "atomic_weight": 91.222
        },
        {
          "name": "Titanium",
          "symbol": "Ti",
          "role": "The other B-site cation. Together with zirconium it sets the composition at the morphotropic phase boundary.",
          "atoms": 0.48,
          "atomic_weight": 47.867
        },
        {
          "name": "Oxygen",
          "symbol": "O",
          "role": "Three oxygen atoms per formula unit.",
          "atoms": 3,
          "atomic_weight": 15.999
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The powder carries serious health hazards on the supplier's safety data sheet, so handle it as lead.",
        "points": [
          {
            "label": "The powder",
            "line": "The supplier SDS classes it as Repr. 1A (may damage fertility or the unborn child), STOT RE 2 (damage through prolonged or repeated exposure) and Acute Tox. 4 (harmful if swallowed or inhaled). The signal word is Danger."
          },
          {
            "label": "Limits",
            "line": "The US exposure limit is 0.05 mg/m3 as lead, and the blood-lead biological limit is 30 ug per 100 ml."
          },
          {
            "label": "In a fire",
            "line": "Lead oxide fume, zirconium oxide and titanium oxides can be released. Firefighters should wear a self-contained respirator."
          }
        ],
        "level": 0,
        "verdict": "Classed as a reproductive toxicant"
      },
      {
        "title": "Handling and storage",
        "points": [
          {
            "label": "Storage",
            "line": "Keep the container tightly sealed, in a cool, dry place with good ventilation."
          },
          {
            "label": "Waste",
            "line": "Do not let the product enter drains or watercourses. Dispose of it under local, regional and national rules."
          },
          {
            "label": "Heat",
            "line": "PI recommends operating PZT only up to 50 % of its Curie temperature. For PIC 255 that is half of 350 degC, or 175 degC."
          }
        ]
      }
    ]
  },
  "updated": "2026-10-26",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 17,
    "unreachable": 3,
    "caveats": 1,
    "note": "Written by an AI assistant on 2026-10-26 from pages read in this run. Values come from the PI Ceramic and CeramTec datasheets, a 2018 open-access paper and the Stanford Advanced Materials SDS. Three sources could not be opened: the Promsawat 2017 aging paper (Cranfield repository), the Southampton aging-rate eprint, and PubChem element pages."
  },
  "sources": {
    "pi-pzt": {
      "title": "PI Ceramic: Piezo Ceramics Material Data (standard and lead-free tables)",
      "id": "PI Ceramic GmbH, revision 08/2024",
      "url": "https://www.pi-usa.us/fileadmin/user_upload/pi_us/files/technotes_whitepapers/Piezo_Ceramics_Material_Data.pdf",
      "year": 2024,
      "kind": "datasheet",
      "license": "manufacturer datasheet, cited not reproduced"
    },
    "ceramtec-hard": {
      "title": "CeramTec: Piezoceramic Hard Materials (Sonox P4, PZT401, PZT406, Sonox P8, PZT807)",
      "id": "CA220108/EN/2604/IM",
      "url": "https://ceramtec-group.com/fileadmin/user_upload/Corporate/11_Downloads/04_Piezo_Ceramics/CeramTec_Datasheet_Piezo_Hard_Materials_EN.PDF",
      "year": 2026,
      "kind": "datasheet",
      "license": "manufacturer datasheet, cited not reproduced"
    },
    "seshadri2018": {
      "title": "Unexpectedly high piezoelectricity of Sm-doped lead zirconate titanate in the Curie point region",
      "id": "doi:10.1038/s41598-018-22566-5 (Sci Rep 8, 4120, PMC5841290)",
      "url": "https://pmc.ncbi.nlm.nih.gov/articles/PMC5841290/",
      "year": 2018,
      "kind": "paper",
      "license": "open access, Creative Commons (as listed by PMC)"
    },
    "stanford-pzt-sds": {
      "title": "Safety Data Sheet: PZT (Lead Zirconate Titanate), Stanford Advanced Materials, CAS 12626-81-2",
      "id": "CAS 12626-81-2; revised 29/11/2022",
      "url": "https://samaterials.com/tds/1697120751-1966-lead-zirconate-titanate-powder-sds.pdf",
      "year": 2022,
      "kind": "datasheet",
      "license": "supplier document, linked not reproduced"
    },
    "nasa-stacks-2008": {
      "title": "Characterization of Piezoelectric Stacks for Space Applications",
      "id": "NTRS 20110013164 (presented 2008; Sherrit, Jones, Aldrich, Blodget, Bao, Badescu, Bar-Cohen)",
      "url": "https://ntrs.nasa.gov/citations/20110013164",
      "year": 2008,
      "kind": "report",
      "license": "public domain (NASA)"
    },
    "usgs-mcs2026-lead": {
      "title": "Mineral Commodity Summaries 2026: Lead",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-lead.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-mcs2026-zirconium": {
      "title": "Mineral Commodity Summaries 2026: Zirconium and Hafnium",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-zirconium-hafnium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "tuv-rohs-2025": {
      "title": "Europe directive (EU) 2025/2363 amending the RoHS directive on exemptions for lead in glass or ceramic components (summary)",
      "id": "Directive (EU) 2025/2363",
      "url": "https://www.tuv.com/regulations-and-standards/en/europe-directive-eu-2025-2363-amending-rohs-directive-on-exemptions-for-lead-in-glass-or-ceramic-components-7-c-i-7-c-ii-7-c-v-7-c-vi.html",
      "year": 2025,
      "kind": "web",
      "license": "third-party summary, cited not reproduced"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/lead-titanate-pzt/"
}