Zirconia ceramic

Morgan’s injection-molded 3 mol% yttria-stabilized zirconia has indicative test-piece values of greater than 800 MPa four-point flexural strength at 20°C and greater than 10¹⁰ Ω·cm volume resistivity at 100°C. Specify the stabilizer and manufacturing route, then set acceptance values for the finished component. Morgan yttria-stabilized zirconia datasheet

Identify the formulation and ceramic family

CoorsTek distinguishes magnesia partially stabilized zirconia, yttria partially stabilized zirconia, and zirconia-toughened alumina (ZTA). ZTA is an alumina-based composite family, not another name for a predominantly zirconia material. Its brochure separately identifies sintered yttria grades and grades strengthened by hot isostatic pressing (HIP). Retain that processing distinction when comparing or substituting material.

Its examples include Dura-Z and Technox 500 in the magnesia-stabilized family, YTZP and Technox 2000 as sintered yttria grades, and HIPped YTZP, YZ110HS and Technox 3000 as HIPped options. These product names identify different selections, rather than a menu of interchangeable values. CoorsTek, Zirconia Materials

Stabilizer concentration must retain its units. Tosoh's powder brochure identifies TZ-3Y-E as a 3 mol% yttria grade and separately lists a powder-composition range of 5.2 ± 0.5 wt% Y₂O₃. Mole percent and mass percent are not interchangeable labels. The same brochure distinguishes powder chemistry from typical properties of sintered bodies; purchasing a compliant powder does not establish the finished ceramic's density or strength. Tosoh, The Fascinating World of Tosoh Zirconia

What transformation toughening means

Superior Technical Ceramics explains that stress near a crack in Y-TZP can induce transformation from tetragonal to monoclinic crystal structure, accompanied by local volume expansion that resists further crack growth. Stabilizer concentration and grain size influence stability. The cited note carries 10.28.2013 alongside a 2014 copyright; these are printed document markings, not dates inferred from search results.

Transformation toughening is a mechanism, not a guarantee against brittle fracture. Do not interpret a high toughness value as metal-like ductility or permission to ignore notches, impact, surface damage or tensile stress. The final design still requires an appropriate ceramic failure assessment. Superior Technical Ceramics, Transformation Toughening of Y-TZP

A bounded manufactured-grade example

Morgan's 3 mol% Yttria-Stabilised Zirconia for Ceramic Injection Moulding sheet is dated 22 February 2018. Its description says 99% ZrO₂, Y₂O₃ and HfO₂ in combination; this must not be shortened to “99% pure ZrO₂.” Selected reported values are:

The sheet explicitly describes test-piece values as indicative, variable with component design and not guaranteed. They are not finished-part acceptance limits or structural allowables. A four-point bending result is also not a tensile-strength result. Morgan Advanced Materials, Yttria Stabilised Zirconia datasheet

Match specimen dimensions, surface preparation, temperature, method and statistical basis before comparing test results.

Temperature and electrical behavior

A material's suitability for a wear part does not establish suitability for electrical insulation. Ceramco specifically cautions that its YTZP may be unsuitable for long-term water immersion and for applications at 500 °C and above where electrical conductivity must be avoided. This is a supplier's application caveat, not a universal temperature threshold for every stabilized zirconia.

Specify operating and transient temperatures, load, atmosphere, electrical field and exposure duration separately. Confirm electrical properties at the relevant temperature instead of extrapolating a room-temperature insulating result. A melting-point or furnace-use statement cannot establish continuous loaded performance for an arbitrary assembly. Ceramco, Zirconia application guidance

Water, steam and aging require qualification

Superior Technical Ceramics' low-temperature-degradation paper describes moisture-associated destabilization of YTZP's tetragonal phase, progressing from the surface and potentially affecting integrity. The paper's footer reads Revised 01.05.2021. Its discussion also identifies formulation and surface modifications as possible approaches to improved resistance. It does not justify treating all zirconias as equally susceptible or an alternative stabilizer as universally immune.

For wet or steam-exposed service, qualify the actual material, surface condition and exposure history. Define liquid chemistry, temperature, pressure, duration, cycling and applied stress, together with required retained properties. An accelerated test needs a justified relationship to service before it can support a lifetime claim. Superior Technical Ceramics, Low Temperature Degradation of YTZP

Tosoh illustrates the importance of processing by discussing improved hydrothermal-aging resistance for TZ-3Y-E sintered under particular conditions and showing comparisons between separately identified grades and sintering temperatures. Its brochure also presents aging and translucency comparisons with their own exposure and processing labels. Those comparisons support keeping powder grade and sintering history in the record; they are not universal operating recipes or automatic qualification of a finished component. Tosoh, processing and aging comparisons

Manufacturing, finishing and handling

Specify whether the supplier delivers powder, a formed blank, sintered stock or a finished ground/polished part. CoorsTek lists pressing, extrusion and injection molding alongside finishing operations such as precision grinding, lapping and polishing. Agree the required geometry, dimensional tolerances, critical surfaces and final material condition rather than assuming a forming route alone establishes precision. CoorsTek, manufacturing and finishing options

For installation, define contact surfaces, fits, edge details and load transfer. Assess the final assembly rather than relying on a generic assertion that zirconia expands similarly to a metal. Inspection should address critical dimensions and surface/edge defects using agreed acceptance criteria.

CoorsTek's 01964 B Zirconia Ceramic SDS identifies fired/sintered formed parts and several named grades. Its history gives February 15, 2017, version 2, despite a 2018 copyright footer. It distinguishes dust generated by grinding, sanding or machining from intact parts, noting possible mechanical eye and respiratory irritation at high dust concentrations. Follow the applicable exposure controls and eye protection, and obtain current product-specific instructions before processing; a formed-part SDS should not be substituted for raw-powder guidance. CoorsTek, Zirconia Ceramic SDS

Purchase and release requirements

Record manufacturer and grade, stabilizer identity and composition basis, manufacturing/HIP condition, dimensions, surface finish, batch traceability and required tests. Distinguish supplier typical data from contractual limits and approved design values. Define environmental aging and electrical requirements independently of initial mechanical strength. No revision date is assigned here to the undated CoorsTek materials brochure, Tosoh brochure or Ceramco webpage from their filenames or crawl dates.

Related reference

Material selection through production