1、CEN ENrb23-2 93 EUROPEAN STANDARD NORMEEUROPENNE EUROPISCHE NORM 3404589 O050692 04T = EN 623-2 September 1993 UDC 666.5/.6: 620.1: 531.75 Descriptors: Ceramics, characteristics, tests, determination, bulk density, porosity, quality English version Advanced technical ceramics - Monolithic ceramics -
2、 General and textural properties - Part 2 : Determination of density and porosity Cramiques techniques avances - Cramiques monolithiques - Proprits gnrales et structurales - Partie 2 : Dtermination de la masse volumique et de la porosit Hochleistungskeramik - Monolithische Keramik - Allgemeine und s
3、trukturelle Eigenschaften - Ri1 2 : Bestimmung von Dichte und Porositt This European Standard was approved by CEN on 1993-08-30. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard
4、 without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other langu
5、age made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland,
6、 Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O 1993 Copyright reserved to CEN members
7、 Ref. No. EN 623-2 : 1993 E CEN EN*b23-2 93 = 3404589 0050b93 T8b Page 2 EN 623-2 : 1993 Foreword This European Standard has been prepared by %chnical Committee CEN/TC 184 Advanced technical ceramics the secretariat of which is held by BSI. EN 623 Advanced technical ceramics - Monolithic ceramics -
8、General and textural properties consists of four Parts: Part 1 : Determination of the presence of defects by dye penetration tests Part 2 : Determination of density and porosity Part 3 : Determination of grain size) part 4 : Determination of surface roughness1) The European Standard shall be given t
9、he status of a national standard, either by publication of an identical text or by endorsement, at the latest by March 1994, and conflicting national standards shall be withdrawn at the latest by March 1994. In accordance with the CENXENELEC Internal Regulations, the following countries are bound to
10、 implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Contents Foreword 1 Scope 2 Normative references 3 Definitions 4 5 6 Method by measuremen
11、t of Statement of accuracy and errors The evacuation method (Method 1) dimensions and mass (geometric buk density) (Method 2) 7 Test report Page 2 3 3 3 4 4 6 7 Parts 3 and 4 of this European Standard will be published as ENV. CEN EN+b23-2 93 m 3404589 0050694 912 m 1 Scope This Part of EN 623 descr
12、ibes methods for determination of the bulk density, apparent solid density, and apparent porosity of advanced technical ceramics. Two methods are described and are designated as Methods 1 and 2, as follows. Method 1. Determination of bulk density, apparent solid density and apparent porosity by the
13、evacuation method. NOTE 1. This method is not suitable for the determination of apparent porosity of less than 1 %. A method for determining the presence of defects and surface porosity in this type of material is given in EN 623 : lart 1. NOTE 2. The method is also not suitable for materials which
14、are known to have an average pore size of greater than 200 pm. Method 2. Determination of bulk density only, by measurement of dimensions and mass. NOTE 3. Neither of these test methods measures total porosity including open and closed pores. This parameter may be calculated from the test results of
15、 Method 1 if the true density of pore-free material is known. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed herea
16、fter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN 623-1 Advanced technical ceramics
17、 - Monolithic ceramics - General and textural properties Part 1 : Determination of the presence of defects by dye penetration tests General criteria for the operation of testing laboratories Advanced technical ceramics - Methods of testing monolithic ceramics - Guidance on the sampling and selection
18、 of test pieces IS0 758 : 1976 Liquid chmical products for industrial use - Deterrninution of density at 20 OC Micrmter callipers for external Steel - Hardness conversions Vernier callipers reading to EN 45001 EN 1006 IS0 3611 : 1978 meclsurement IS0 4964 : 1984 IS0 6906 : 1984 0,02 mm Page 3 EN 623
19、-2 : 1993 3 Definitions For the purposes of this lart of EN 623 the following definitions apply. 3.1 open pores Pores that are penetrated by an immersion liquid in vacuum, or that are connected with the atmosphere, either directly or via one another. 3.2 closed pores Pores that are not penetrated by
20、 the immersion liquid, or that are not connected with the atmosphere. 3.3 bulk volume vb The sum of the volumes of the solid material, the open pores and the closed pores in a porous body. 3.4 true volume The volume of a body occupied by solid material, excluding all forms of porosity. 3.5 apparent
21、solid volume Vs The sum of the volume of the closed pores and true volume. 3.6 bulk density Pb The ratio of the mass of the dry material of a porous body to its bulk volume. 3.7 geometric bulk density The mass per unit total volume of a material including ali porosity accessible and in accessible fr
22、om the surface, the volume being calculated from linear dimensions. 3.8 apparent solid density ps The ratio of the mass of the dry material to its apparent solid volume. 3.9 apparent porosity na The ratio of the total volume of the open pores in a porous body to its bulk volume. 4 Statement of accur
23、acy and errors The minimum accuracy of measurement of the parameters used in calculation of densities and porosities is given in table 1. CEN EN*b23-2 93 W 3404589 0050b95 859 W Method 1: Evacuation method (see clause 5) Page 4 EN 623-2 : 1993 Method 2: Geometric bulk density see clause 6) Ittble 1.
24、 Accuracy and errors of density and porosity measurement Minimum test piece mass in g 1 2 30 Accuracy of weighing in g 0,0001 0,001 0,Ol I- Accuracy of measurement of dimension) Accuracy of measurement of density 0,0001 0,001 0,001 of immersion liquid, (Mg/m3); see 5.5 and table 2 Accuracy of densit
25、y measurement (%I O, 3 0,Ol mm or 0,05 % of smallest dimension 2,o 0,001 - 190 Minimum test piece dimension in mm I - 1370 5 The evacuation method (Method 1) 5.1 Principle The mass of dry test piece is determined by weighing, then its apparent mass when immersed in a liquid with which it has been im
26、pregnated under vacuum, and then its mass in air while still soaked with the liquid. From these values its bulk density and apparent porosity are determined by calculation. 5.2 Apparatus 5.2.1 Drying oven, capable of maintaining a temperature of 110 OC f 5 OC. 5.2.2 Balame with accuracy in accordanc
27、e with clause 4. 5.2.3 A bridge, to be placed over the load-bearing scale pan of the balance (see 5.2.2), if the balance is not equipped for suspension loading. 5.2.4 Evacuating equipment, capable of reducing the pressure to a value less than 2500 Pa (25 mbar), and a means of measuring the pressure
28、used. NOTE. If a rotary vacuum pump is used, it should be fitted with a moisture trap, to minimize the mixing of water and the pump lubrication system. 5.2.5 Degreased metul wire, of diameter not more than 0,15 mm. 5.2.6 Cradle to contain test piece(s) (optional). 5.2.7 Immersion liquid, which may b
29、e either: a) cold distilled water, containing a dilute solution of a surface active agent (concentration not more than 0,Ol %), the addition of which does not change the densities given in table 2; or b) an organic liquid, which shall be used for materiais that are sensitive to contact with water or
30、 that cannot be fully wetted by water. NOTE. Some materials may chemically react with water, others such as boron nitride are not wetted by water. Where test pieces of smaller volume (1 cm3 to 10 cm3) (see 5.3.1) are used, and the error caused by evaporation of liquids is comparatively high, dibutyl
31、 phthalate should be used. 5.2.8 ?tmrnmter, capable of measuring to f 0,l K. 5.2.9 Glass beak, of a size allowing adequate clearance of its walls by the test piece. 5.2.10 Desiccator, for storage of test pieces. 5.2.11 Manometer. 5.2.12 Absorbent cloth or t.lssue paper. 5.3 Test pieces 5.3.1 Materia
32、ls for testing shall be sampled in accordance with the guidance given in ENV 1006. Test pieces shall be either whole or broken ceramic products, or shall be cut from blocks or rods of the same material. The bulk volume of a test piece shall be not less than 1 cm3, and its mass shall be greater than
33、1 g (see table 1 and note 2). NOTE 1. When the apparent porosity is greater than 10 %, the ratio of the longest to the shortest dimension of a test piece should not exceed 2 : 1. NOTE 2. For test pieces of mass 1 g to 3 g, significant sources of error include temperature, air content of liquid and t
34、he consistency of the liquid level position on the suspension wire. These factors should be kept constant. 5.3.2 If any surface treatment such as the removal of skin is carried out this shall be reported in the test report (see clause 7). NOTE. Since it is necessary to sponge the surface of the test
35、 piece to remove surface moisture, the test pieces should not have inaccessible external surfaces or very rough surfaces. CEN EN*623-2 93 = 3Li04589 0050696 795 5.4 Procedure 5.4.1 Determination of the mass of the dry test piece Dry the test piece in the oven (see 5.2.1) at 110 OC f 5 OC to constant
36、 mass, i.e. until two successive weighings made before and after at least 2 h in the drying oven do not differ by more than 0,03 %. Before each weighing, place the test piece in the desiccator (see 5.2.10),until it has cooled to room temperature, and weigh it as quickly as possible after removal fro
37、m the desiccator. The mass thus determined is the mass of the dry test piece (ml), weighed in accordance with table 1. 5.4.2 Soaking of test piece Place the cooled and dried test piece in an airtight vessel. Seal the vessel and evacuate it until a pressure of less than 2500 Pa is attained; maintain
38、this vacuum for at least 15 min. In order to ensure that all the air has been removed from the test piece, isolate or disconnect the vessel from the vacuum pump and use the manometer (see 5.2.11) to check that the pressure does not rise through any degassing of the test piece. Progressively introduc
39、e the immersion liquid in such a way that, after 3 min, the test piece is covered by about 20 mm of liquid. Reconnect the vessel to the vacuum pump and maintain this reduced pressure for 30 min, then switch off the pump and open the vessel to ambient air pressure. Wait for at least a further 30 min
40、to ensure complete penetration of the test piece by the liquid. NmE. If there is any doubt about the completion of penetration within 30 min, this period may be extended by agreement between parties as required. 5.4.3 Determination of the apparent mass of the immersed test piece Suspend the test pie
41、ce by the thin wire (see 5.2.5) from the load-pan suspension point of the balance, perpendicular to the liquid, and weigh it while completely immersed in a quantity of the immersion liquid, contained in the beaker (see 5.2.9), standing on the bridge (see 5.2.3) if used. Remove bubbles from the surfa
42、ce of the test piece and weigh. Remove the test piece 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 piece (mz), weighed in accordance with table 1. Determine the temp
43、erature of the immersion liquid, using the thermometer (see 5.2.8). 5.4.4 Determination of the mass of the soaked test piece Remove the test piece from the liquid and, without waiting, sponge it quickly and carefully with a damp, lint-free absorbent cloth or tissue (see 5.2.12) to remove droplets an
44、d the surface film of liquid, but avoid drawing out liquid from the pores of the test piece. Page 5 EN 623-2 : 1993 Immediately weigh the test piece in air. Take care to ensure that evaporation of the immersion liquid does not lead to any appreciable loss in mass during the weighing operation. NCYTE
45、. If such loss occurs, the test should be repeated using a different immersion liquid (see note to 6.2.7). Record the mass thus determined as the mass of the soaked test piece (m), weighed in accordance with table 1. Repeat the immersion, drying and weighing. If the results for each test piece diffe
46、r by more than the relevant accuracy figures given in table 1, repeat the test until two sets of figures meet these criteria. 5.5 Determination of the density of the immersion liquid Determine the density of the liquid used in the operation at the temperature of the test, using the method given in I
47、S0 758 : 1976, to the accuracy given in table 1. NCTE 1. For distilled water, the density at various temperatures is given in table 2. NOTE 2. As many organic solvents have high coefficients of volume thermal expansion, the determination of density of the liquid should be carried out at the same tem
48、perature as that of the measurement of the apparent mass of the immersed test piece (see 5.4.3) Igble 2. Density of distilled water as a function of temperature between 15 OC and 30 OC Temperature, OC 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Density, p Mg/m3 0,99910 0,99894 0,99877 0,99860 0,
49、99841 O, 99820 0,99799 0,99777 0,99754 0,99730 0,99704 0,99678 0,99651 0,99623 O , 99594 O, 99565 Kg/m3 999,lO 998,94 998,77 998,60 998,41 998,20 997,99 997,77 997,54 997,30 997,04 996,78 996,51 996,23 995,94 995,65 CEN EN*b23-2 93 3404587 0050b77 621 D Page 6 EN 623-2 1993 5.6 Calculation of results 5.6.1 Calculate the bulk density Pb, in either megagrams per cubic metre or kilograms per cubic metre from the following equation: 5.6.2 Calculate the apparent solid density ps, in either megagrams per cubic metre or kilograms per cubic metre. 5.6.3 Calculate the appa
