1、Designation: C 824 91 (Reapproved 2005)Standard Practice forSpecimen Preparation for Determination of Linear ThermalExpansion of Vitreous Glass Enamels and Glass EnamelFrits by the Dilatometer Method1This standard is issued under the fixed designation C 824; the number immediately following the desi
2、gnation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the prep
3、aration of vitreous glassenamels and glass enamel frit specimens for the measurementof linear thermal expansion using Test Method E 228.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to a
4、ddress all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements, see Section 6.2. Refer
5、enced Documents2.1 ASTM Standards:E 228 Test Method for Linear Thermal Expansion of SolidMaterials With a Vitreous Silica Dilatometer23. Significance and Use3.1 The dilatometer method of measuring linear thermalexpansion of vitreous glass enamels and glass enamel frits hasthe advantage of simplicity
6、, lends itself to automatic, self-recording arrangements, and requires test specimens of simpleconfiguration.4. Apparatus4.1 Powder Pressing Die, whose top and bottom sectionsare free to move such that density variations within the bar areminimized (see Fig. 1).4.2 Hydraulic Press.4.3 Furnace, for f
7、iring test specimen, electrically heated andcontrolled to a minimum rate of heating of 1C/min from roomtemperature to the maximum temperature of the test. It shall beso designed that the temperature variation over the length ofthe test specimen shall be less than 2C during the entire rangeof heating
8、.4.4 Scale or Caliper, capable of measuring the length of thetest specimen to an accuracy of 0.1 %.5. Reagents and Materials5.1 Hydroxypropyl Cellulose Solution in Water(1 weight% ).5.2 Powder Sample.6. Hazards6.1 Appropriate ventilation should be provided when han-dling powdered frits or enamels co
9、ntaining toxic ingredients.6.2 Ingestion or inhalation of test materials should beavoided. Protective clothing such as gloves, respirators, etc.,may be advisable. If ingestion occurs, seek medical attentionimmediately.1This practice is under the jurisdiction of ASTM Committee C14 on Glass andGlass P
10、roducts, and is the direct responsibility of Subcommittee C14.10 on GlassDecoration.Current edition approved Sept. 1, 2005. Published October 2005. Originallyapproved in 1976. Last previous edition approved in 2000 as C 824 91 (2000).2Withdrawn.NOTE 1Material: No. 316 stainless steel.FIG. 1 Powder P
11、ressing Die1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.3 Caution should be exercised when placing specimens infurnaces. Tongs and insulated gloves should be used. To avoidaccidental contact and serious thermal burns, care shoul
12、d betaken to guard hot-fired specimens while they are being cooled.7. Test Specimen Preparation7.1 Collect vitreous glass enamel or glass enamel fritparticles within the 60 to 200 mesh particle size range andcombine with 0.5 to 1.0 weight % of the hydroxypropylcellulose solution.7.2 Using the die in
13、 4.1 and the hydraulic press in 4.2, pressthe powder prepared in 7.1 at 34 MPa (5000 psi) into a barconsistent with the dimensional guidelines found in TestMethod E 228.7.3 Fire and anneal the test specimen prepared in 7.2 usinga time/temperature cycle consistent with that used commer-cially for the
14、 vitreous glass enamel or glass enamel fritinvolved.7.4 The ends of the fired test specimen shall conform to theguidelines given in Test Method E 228.7.5 Measure the length of the test specimen to an accuracyof 0.1 % with the test specimen at a temperature equivalent tothe temperature of the dilatom
15、eter at the initiation of the testprocedure (normally room temperature).ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of
16、 any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments ar
17、e invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not rec
18、eived a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C 824 91 (2005)2
