1、November 2007DEUTSCHE NORM English price group 9No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 81.060.30!$JF$“1393501
2、www.din.deDDIN EN 725-10Advanced technical ceramics Methods of test for ceramic powders Part 10: Determination of compaction propertiesEnglish version of DIN EN 725-10:2007-11Hochleistungskeramik Prfverfahren fr keramische Pulver Teil 10: Bestimmung der VerdichtungseigenschaftenEnglische Fassung DIN
3、 EN 725-10:2007-11SupersedesDIN EN 725-10:1997-04www.beuth.deDocument comprises 16 pagesDIN EN 725-10:2007-11 2 National foreword This standard has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics” (Secretariat: BSI, United Kingdom). At present a DIN committee does not ex
4、ist for this standard since the parties concerned have not shown any interest in work on the subject. The Normenausschuss Materialprfung (Materials Testing Standards Committee) is obliged to publish the standard, however, as the subject falls in its domain. Amendments This standard differs from DIN
5、EN 725-10:1997-04 as follows: a) Clause 2 “Normative references” has been extended. b) The test report in clause 8 has been revised and extended. Previous editions DIN EN 725-10: 1997-04 EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 725-10September 2007ICS 81.060.30 Supersedes EN 725-10:1997 Eng
6、lish VersionAdvanced technical ceramics - Methods of test for ceramicpowders - Part 10: Determination of compaction propertiesCramiques techniques avances - Mthodes dessai despoudres cramiques - Partie 10: Dtermination desproprits de compactionHochleistungskeramik - Prfverfahren fr keramischePulver
7、- Teil 10: Bestimmung derVerdichtungseigenschaftenThis European Standard was approved by CEN on 11 August 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alter
8、ation. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by transl
9、ationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Gr
10、eece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement
11、Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 725-10:2007: EEN 725-10:2007 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Principle4 4 Symbols 4 5 Apparatus .4 6
12、Procedure .5 6.1 Drying5 6.2 Quantity 5 6.3 Cleaning of the die and punches .5 6.4 Powder testing conditions5 6.5 Lubrication .5 6.6 Compacting pressures6 6.7 Compacting and ejection 6 7 Expression of results 7 7.1 Calculation7 7.2 Compaction curve7 8 Test report 7 Annex A (informative) Repeatabilit
13、y and reproducibility 11 Annex B (informative) Example of presentation of test report .12 B.1 General12 B.2 Sample description and preparation .12 B.3 Test conditions 12 B.4 Determination of the density of the compacts .13 B.5 Calculation of density .13 Bibliography 14 EN 725-10:2007 (E) 3 Foreword
14、This document (EN 725-10:2007) has been prepared by Technical Committee CEN/TC 184 “Advanced technical ceramics”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the lat
15、est by March 2008, and conflicting national standards shall be withdrawn at the latest by March 2008. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such
16、 patent rights. This document supersedes EN 725-10:1996. EN 725 Advanced technical ceramics Methods of test for ceramic powders was prepared in parts as follows: Part 1: Determination of impurities in alumina Part 2: Determination of impurities in barium titanate Part 3: Determination of the oxygen
17、content of non-oxides by thermal extraction with a carrier gas Part 4: Determination of oxygen content in aluminium nitride by XRF analysis Part 5: Determination of particle size distribution Part 6: Determination of the specific surface area withdrawn Part 7: Determination of the absolute density w
18、ithdrawn Part 8: Determination of tapped bulk density Part 9: Determination of un-tapped bulk density Part 10: Determination of compaction properties Part 11: Determination of densification on natural sintering Part 12: Chemical analysis of zirconia Parts 6 and 7 of the series were superseded in 200
19、5 by EN ISO 18757 and EN ISO 18753 respectively. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Ge
20、rmany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. EN 725-10:2007 (E) 4 1 Scope This Part of EN 725 describes methods for the determination of th
21、e compaction behaviour of ungranulated or granulated ceramic powders, when subjected to uniaxial compressive loading in a rigid die, under specified conditions. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, onl
22、y the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories (ISO/IEC 17025:2005) 3 Principle The powder is compacted uniaxially
23、 in a rigid die by double-action pressing. Samples of the powder may be pressed either at a single pressure or at a series of pressures. After ejection from the die, the apparent geometrical density of the compact is determined. Where one pressure is used, the density obtained represents the compact
24、ion properties of the powder at that pressure. Where more than one pressure is used, the densities obtained are utilized for drawing the compaction curve of the powder, which is a plot of its density as a function of the compacting pressure. 4 Symbols The symbols and associated units used in this pa
25、rt of EN 725 are set out in Table 1. Table 1 Symbols and units Symbol Designation Unit geom m V Apparent geometrical density Mass of the compact Volume of the compact kg/m3 g cm3If the apparent density is measured at one pressure only, for example 200 MPa, the symbol becomes, e.g. geom (200). 5 Appa
26、ratus 5.1 Die, which shall be made from hard material (e.g. tungsten carbide). The cylindrical die shall contain two punches for producing cylindrical compacts and shall be of the floating type or of the type suspended from a spring. The die shall be capable of making compacts of diameter 20 mm to 2
27、6 mm with a height to diameter ratio between 0,3 and 0,5, with tolerances as indicated in Figure 1. The upper part of the die shall be (preferably) designed to avoid damage to the compact during the ejection phase due to springback. An ejection cone of height 5 mm, allowing an increase of the diamet
28、er at the top of the die of approximately 1 %, as shown in Figure 1, should be used. EN 725-10:2007 (E) 5 The die may be fitted with a venting valve. 5.2 Press, capable of applying sufficient force with an accuracy of 1 %. 5.3 Balance, capable of weighing at least 10 g, to the nearest 0,005 g. 5.4 M
29、icrometer, conforming to ISO 3611, or other suitable measuring device for measuring the dimensions of the compacts with a resolution of 0,01 mm. 6 Procedure 6.1 Drying A sample containing organic additives shall be used as received. A sample without organic additives shall be dried at 110 C 5 C unti
30、l constant mass is attained. Store in a desiccator until the test is performed. During drying the sample layer shall have a maximum thickness of 5 mm. 6.2 Quantity Three compacts with dimensions as specified in 5.1 shall be prepared for each pressure used in the determination. The quantity of powder
31、 shall be sufficient for the preparation of the total number of compacts (3 x the number of pressures used). NOTE If necessary, preliminary tests should be made to establish the quantity of powder necessary to conform to this requirement. 6.3 Cleaning of the die and punches Wipe the die cavity and t
32、he punches with a soft, clean paper towel soaked with an appropriate solvent, such as acetone. Allow the solvent to evaporate. 6.4 Powder testing conditions Powders shall be compacted: either 1) in a dry die NOTE For powders not containing a lubricant, seizure and excessive die wear may occur, parti
33、cularly at high compacting pressures or 2) in a die with lubricated walls (see 6.5), or 3) in a dry die, after mixing a lubricant with the powder (see 6.5.3). 6.5 Lubrication 6.5.1 Lubrication of the die walls or of the powder is likely to modify the compaction results. Similarly, depending on the t
34、ype and quantity of lubricant added to the powder, the results may vary within wide ranges. EN 725-10:2007 (E) 6 The test report (see Clause 8) shall therefore mention whether or not lubrication had taken place, and if the lubrication was carried out on the walls of the die or on the powder. Use one
35、 of the following two methods (see 6.5.2 and 6.5.3) if lubrication is applied. 6.5.2 To lubricate the die wall, apply a mixture or a solution of a lubricant in a suitable volatile organic liquid, for example 20 g of stearic acid in 980 g of acetone. After any excess liquid has drained away, allow th
36、e solution adhering to the walls to evaporate leaving a thin layer of lubricant. Alternatively, press in the die, before testing, inert spheres (polyurethane spheres for instance) coated with lubricant. After removal of the pressed disc of inert material, a thin layer of lubricant remains on the wal
37、ls of the die. 6.5.3 Lubricate the powder to be tested by thoroughly mixing it with an appropriate amount of a suitable solid lubricant (for example zinc stearate or stearic acid). 6.6 Compacting pressures For plotting the compaction curve of a powder, a minimum of four pressures in a range agreed b
38、etween the parties concerned shall be used. If compaction properties are to be determined at a single pressure only, this pressure shall also be agreed between parties prior to the test. 6.7 Compacting and ejection 6.7.1 Position the die using spacers between the die and the foot of the lower punch,
39、 to leave a free volume in the die large enough to contain the bulk powder (see Figure 2). 6.7.2 Pour a known weight of powder into the die, sufficient to almost fill the die cavity. The weight shall be the same for each compact in a series. 6.7.3 Remove any remaining powder adhering to the wall of
40、the die cavity. 6.7.4 Insert the upper punch into the die. 6.7.5 Position the die with its punches between the plate ends of the press. Apply and release a preliminary pressure. This pressure shall be lower than the lower pressure used in the test. Remove the spacers supporting the die. NOTE 1 If th
41、e die is supported by springs or by a similar system, it is unnecessary to apply this preliminary pressure. Apply the selected test pressure and maintain for 1 min. NOTE 2 Taking into account the different press technology, it is difficult to specify a rate of increase of the force as well as the di
42、splacement speed of the punch. 6.7.6 Perform decompression slowly (for example 10 mm/min) to avoid breaking the compact. 6.7.7 Eject the compact by using a relative movement between the die and the lower punch. Transfer the compact to a desiccator for 1 h to allow a possible expansion due to springb
43、ack. Remove the compact from the desiccator, weigh to the nearest 0,005 g and measure to the nearest 0,01 mm, the dimensions (both height and diameter) in 3 different places, and take the average. EN 725-10:2007 (E) 7 7 Expression of results 7.1 Calculation The apparent geometrical density of the co
44、mpact is given by the equation: Vmgeom= (1) where: m is the mass of the compact, in grams; V is the volume of the compact, in cubic centimetres. Calculate the apparent geometrical density in grams per cubic centimetre and then convert the answer to kilograms per cubic metre, expressed to the nearest
45、 20 kg/m3. Express the compaction properties for a given compacting pressure as the average of the three density figures, calculated to the nearest 20 kg/m3, obtained at the compacting pressure. 7.2 Compaction curve Draw the compaction curve of a powder through points representing the average of det
46、erminations of geom at each of the pressures tested. 8 Test report The test report shall be in accordance with the reporting provisions of EN ISO/IEC 17025, and shall include at least the following information: a) name and address of the testing establishment; b) date of the test; c) on each page, a
47、 unique report identification and page number; d) customer name and address; e) reference to this standard, i.e. determined in accordance with EN 725-10; f) authorizing signature; g) any deviation from the method described, with appropriate validation, i.e. demonstrated to be acceptable to the parti
48、es involved; h) description of the powder (e.g. material type, manufacturer code, batch or code number); i) type, nature and amount of lubricant and any other organic additives used in the test, including: 1) lubrication of the die walls, or no lubrication; 2) lubrication of the powder, or no lubric
49、ation (state how the lubricant has been added); 3) other organic additives; EN 725-10:2007 (E) 8 j) compacting pressures and compaction cycle used; k) dimensions of the compacts; l) results obtained including the compaction curve; m) any comments about the test or test results. EN 725-10:2007 (E) 9 Dimensions in millimetres 251004512= 60-80H16341,61,62,524R550152 x 451525 l0,01 A0,01 ATAKey 1 shrink ring 2 hard material 3 upper punch, l = H - 10 4 lower punch, l = H + 35 Figure 1 Example of tooling to produce a cylindrical compact EN 725-
