EN 1389-2003 pdf download.Advanced technical ceramics – Ceramic composites – Physical properties – Determination of density and apparent porosity.
4.2 Sampling
The sampling method shall be agreed between purchaser and manufacturer.
4.3 Number
At least five test specimens shall be taken from each sample.
NOTE Particular requirements tor Method A are given in 5.3.
4.4 Conditioning and testing atmospheres
The test specimens shall be conditioned in a standard testing atmosphere in accordance with EN ISO 291.
During testing, the apparatus and test specimens shall be maintained at constant temperature, preferably at
(23 ± 2) °C and (50 ± 5) % relative humidity.
5 Method A
5.1 Principle
A test specimen of uniform geometry is dried and weighed. Its volume is determined by measurement of the
appropriate dimensions- The density is calculated as mass per unit volume.
5.2 Apparatus
5.2.1 Balance, with accuracy of 0,1 mg.
5.2.2 Dimension measuring devices, used for measuring linear dimensions of the test specimen. The devices shall be accurate to ± 0,05 mm. Micrometers shall be in accordance with ISO 3611.
5.2.3 Drying oven, capable of maintaining a temperature of (110 ± 5) °C.
5.2.4 DesIccator, for storage of test specimens.
5.3 Test specimen
The shape of test specimens shall be such that the volume can be calculated from the external dimensions, such as rectangular parallelepipeds and right cylinders, discs or rods. Test specimens which do not have uniform dimensions and principal axes orthogonal to within 1 0 shall be ground to achieve such conditions.
where
in is the test specimen mass, expressed in kilogram or in gram;
Vb is the bulk volume of test specimen, expressed in cubic metre or cubec centimetre. The value of bulk density is expressed with a maximum of two significant digits.
6 Method B
6.1 Principle
The mass of the test specimen is determined by weighing in the following conditions:
(1) dry test specimen in air;
(2) test specimen immersed in a liquid which it has been impregnated under vacuum:
(3) test specimen in air while still impregnated with the hquid.
From these values its bulk density and open porosity are determined by calculation.
6.2 Apparatus and reagents
6.2.1 Drying oven, capable of maintaining a temperature of (110 ± 5) °C.
6.2.2 Balance, with an accuracy of 0,1 mg.
6.2.3 Degreased metal wire, of diameter not more than 0.15 mm or cradle (glass or stainless steel with holes), to contain test specimen and able to be easily immersed in the liquid.
6.2.9 Absorbent cloth or tissue paper.
6.2.10 Immersion liquid, which may be either:
a) cold distilled water, containing a dilute solution of a surface active agent (concentration not more than 0,01 %)
b) an organic liquid, which shall be used for materials that are sensitive to contact with water.
6.3 Procedure
6.3.1 Determination of the mass of the dry test specimen
Dry the test specimen in the oven at (110 ± 5) °C to constant mass, after at least 2 h in the drying oven.
Before each weighing. place the test specimen in the desiccator, until it is cooled to room temperature, and weigh it as quickly as possible after removal from the desiccator. The mass thus determined Is the mass of the dry test specimen (m1).
6.3.2 Determination of the apparent mass of the immersed test specimen
Place the cooled and dried test specimen in an airtight vessel. Seal the vessel and evacuate it until a pressure of less than 2 500 Pa is attained; maintain this vacuum for at least 15 mm.
In order to ensure that all the air has been removed from the test specimen, isolate or disconnect the vessel from the vacuum pump and use the manometer to check that the pressure does not rise because of any degasing of the test specimen.
Progressively introduce the immersion liquid in such a way that, alter 3 mm, the test specimen is covered by about 20 mm of liquid.
Reconnect the vessel to the vacuum pump.
Maintain the vacuum until pressure stability is obtained to ensure complete penetration of the test specimen by the liquid.
Suspend the test specimen by the thin wire from the load-pan suspension point of the balance, perpendicular to the liquid, and weigh it while it is completely immersed in a quantity of the immersion liquid, contained in the beaker standing on the bridge (if used).
Remove bubbles from the surface of the test specimen and weigh. Remove the test specimen from the suspension wire, replace the wire in the liquid to the same suspension level and weigh. The difference between the two weighings is the apparent mass of the immersed test specimen (m2). Determine the temperature of the immersion liquid, using the thermometer.EN 1389-2003 pdf download.