Ceramics, whiteware

ASTM C322-82 (1982), Standard practice for sampling ceramic whiteware clays, 12... 

ASTM C325-81 (Re-approved 1997) Standard test method for sieve analysis of ceramic whiteware clays, 235... 

The term porcelain is used here in its European sense. In the USA, it is defined as vitreous ceramic whiteware for technical purposes (ASTM). whereas similar materials for non-technical applications (table ware, sanitary ware, art ware) made by somewhat different processes arc called china (also refer to the note on p. 311). 

Table 8.4a Traditional use Ceramic whiteware classes and their products...

Young s Modulus, Shear Modulus, and Poisson s Ratio Tor Ceramic Whitewares by Resonance," ASTM Standard Test Method C848-78. Annual Book of ASTM Standards, Section 15.02. Am. Soc. Testing Matls., Philadelphia, PA, 1984. 

Alumina Whitewarc. Defined in ASTM - C242 as Any ceramic whiteware in which alumina is the essential crystalline phase. 

Ceramic Whiteware. This term is defined in the USA (ASTM C242) as A fired ware consisting of a glazed or unglazed ceramic body which is commonly white and of fine texture the term includes china, porcelain, semivitreous ware and earthenware. ... 

China. BS 5416 specifies this to be pottery with water absorption 0.2% and tranlucency 0.75% (assessed by comparison with standard test pieces) See also bone china. In the USA, however, ASTM-C242 defines the word as any glazed or unglazed vitreous ceramic whiteware used for nontechnical purposes, e.g. dinnerware, sanitary-ware, and art-ware, provided that they are vitreous. The combined nomenclature (q.v.) equates this term with porcelain (q.v.). 

Dinnerware. An American term (ASTM C242) for ceramic whiteware made in a consistent pattern and a full range of articles to make up a dinner service. Dinosaur. A precision setting machine which automatically cuts, faces and sets green bricks. (Pearne Lacy, USA Craven Fawcett, Leeds). 

E Glass. (Electrical.) A glass of low alkali content (electrically insulating glass fibre. Earthenware. Non-vitreous, opaque, ceramic whiteware. The combined... 

Knoop Hardness. A pyramidal-diamond indentation test. The result is expressed in kg/mm2, the applied load being indicated, eg. Knoop 100 or KlOO a US abbreviation is KHN(Knoop Hardness Number) The test was introduced by F. Knoop, C G Peters and W. B. Emerson (/. Res. Nat. Bur. Stand., 23,39,1939). ASTM C849 describes its application to ceramic whitewares C730 to glass. 

Ovenware. Ceramic whiteware or glassware (casseroles etc) of good thermal shock resistance for use in cooking. Overalls. Workers overalls in the pottery industry are designed without lapels, pockets and other dust traps. 

Overspray. (1) In the application, by spraying, of enamel slip to base-metal or of slop glaze to ceramic whiteware, that proportion of slip or glaze that is not deposited on the ware it is normally collected for re-use. 

Semi-vitreous or Semi-vitrified. These synonymous terms are defined in the USA (ASTM - C242) as signifying a ceramic whiteware having a water absorption between 0.5% and 10%, except for floor tiles and wall tiles which are deemed to be semi-vitreous when the water absorption is between 3% and 7%. S.E.N. Submerged Entry Nozzle. S.E.N.B. Single Edge Notched Beam. 

In Comparative Tests the same constant heat flow is established through the specimen to be measured, and a standard sample of known conductivity. The different temperature gradients across the two samples are compared. (B.S. 1902 Pt. 5.8 specifies a test of this type for refractories, Pt.6 Section 6 a guarded hot-plate test up to 1200 C for ceramic fibre products ASTM C408 one for ceramic whitewares, using a copper standard from 40 to 150°C. 

White s Test. A method for the detection of free lime, for example in Portland cement or dolomite refractories. A few mg of the powdered sample is placed on a glass microscope-slide and wetted with a solution of 5g phenol dissolved in 5 ml nitrobenzene with the addition of two drops of water. Micro-examination (x 80) will reveal the formation of long birefringent needles if free CaO is present. (A. H. White, Industr. Engng. Chem. 1, 5, 1909.) Whiteware. A general term for all those varieties of pottery that usually have a white body, e.g. tableware, sanitary ware and wall tiles. See also ceramic WHITEWARE, which has an ASTM definition. 

ASTM C-242 Terminology relating to ceramic whiteware and related products. 

ASTM, 1997. ASTM C326 - Test Method for Drying and Firing Shrinkage of Ceramic Whiteware Clays. American Society for Testing and Materials. 

Ceramics - Whitewares use a combination of china clay (usually airfloat) and ball clay selected for consistent chemical composition so that firing and vitrifying characteristics of the body are controlled and color and translucency of the fired ware are satisfactory. The ratios used are chosen to optimize green strength, plasticity, and casting behavior. 

Considerable research is now underway into the drying of green ceramic bodies. As one example, current research being performed at Ceram Research in the UK is focussed on two different sectors of the ceramic whitewares... 

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