The uniaxial strength of engineering ceramics is often measured by the well‐known flexure strength test method there is a risk that flexure data are not representative of the properties of fabricated components. Reliability estimates for components based upon statistical extrapolation techniques from flexure data may not be valid. This paper reviews the problem and judges the usefulness of flexure data for design purposes. It is shown that some of the limitations of flexure data apply; to other modes of testing, including direct tension testing

Thermophysical properties for the solid and liquid phases of several Ni based superalloys (CMSX-4, CMSX-10, CM186LC, IN 738 and Rene 80) have been measured. The following properties were measured: heat capacity and enthalpy, thermal expansion coefficient and density, thermal diffusivity, viscosity and surface tension. Analysis of these measurements showed that that γ′ phase (Ni3Al) affected the values for the following properties; Cp, enthalpy, electrical resistivity, thermal diffusivity and conductivity. Relationships have been identified between properties and the γ′ phase content (which can be represented by mass% Al in the alloy). These relations were then used to calculate property values of the alloys from chemical composition. Other relations were developed to estimate the viscosities and surface tensions of Ni based superalloys. The predicted property values were found to be in good agreement with the measured values.

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The driving forces for the recent development of nanoscale features in conventional ceramic materials for both mechanical and functional reasons are discussed, and the causes of some of the resulting property enhancements are identified. Examples from the technical literature are examined, and the potential for future applications is assessed in terms of the tradeoff between enhanced properties and the added costs and difficulties of processing ultrafine powders.

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The development of robust methods for determining fracture toughness and for interlaboratory assessment of results is discussed with respect to procedural standardisation. Acceptable methods are based on meeting several criteria, including ease and cost-effectiveness of testpiece manufacture, the method of introducing a sharp precrack and the acceptability of appropriate fracture toughness analysis. The four simplest methods meeting these criteria are reviewed in detail, together with information on their reproducibility gathered during international round robin exercises. Not all these methods are effective on all materials, and users need to be aware of their limitations. Details of calibration equations and some experimental nuances are given.

Young and older adults were presented with pictures for study. Their recognition of the information was tested at five retention intervals: immediately, and 48 hr, 1 week, 2 weeks, and 4 weeks later. The main finding of interest was that picture recognition did not show an age-related decline until the 1-week retention interval.

Elastic modulus is an intrinsic material property and a key parameter in engineering design and materials development. A wide range of test methods is available for measuring modulus, but there is currently some uncertainty within parts of the user community about the reliability of modulus data, particularly from the tensile test, to the extent that many use standard handbook values in their calculations and designs. This is not recommended and can be addressed through good experimental practice and careful measurement.The paper discusses some of the key practical issues associated with the tensile test that need to be considered to obtain reliable values for Young's modulus such as strain measurement, alignment, data analysis methods, software validation, uncertainty budgets and the use of reference materials.