ASTM_A_367_-_11.pdf

Designation:A36711Standard Test Methods ofChill Testing of Cast Iron1This standard is issued under the fixed designation A367;the number immediately following the designation 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()indicates an editorial change since the last revision or reapproval.1.Scope1.1 These test methods of chill testing apply to gray ironsthat are to be free of chill in the casting and to chilled irons thatare to have a specific depth of chill in the casting.Two testmethods of determining the chilling tendencies of cast iron arecovered as follows.For many applications either test methodwill be satisfactory if test pieces of the proper dimensions areselected.1.1.1 Test Method A,Wedge TestThis test is generallybetter adapted to the higher strength gray irons.The acceleratedcooling rate to induce the formation of a chill is brought aboutthrough the design of the test specimen.This test method issimpler than Test Method B since maintenance of chill blocksor plates is not necessary.1.1.2 Test Method B,Chill TestThis test is better adaptedto the softer grades of gray iron and should be used if thecasting is to have a specified depth of chill.The chill in thistype of test is induced by casting one edge of the test specimenagainst a metal or graphite chilled plate or block.1.2 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.2.1 The metric equivalency charts in Figs.1 and 2 areprovided for information only.1.3 This standard does not purport to address 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.TEST METHOD AWEDGE TEST2.Application2.1 Selection of a test specimen of appropriate dimensionswill allow measurement of chilling tendencies of all gray ironcompositions,with the exception of those having siliconcontents much over 2.50%together with carbon contents over3.50%.3.Test Specimens3.1 The patterns for the test specimens shall be made ofmetal to the dimensions shown in Fig.1.With the exception ofthe length of the test specimen,dimensions shall not vary morethan 6132in.(0.8 mm).The tolerance on the length of thespecimen shall be 618in.(3.2 mm).The radius on the apex ofthe wedge should be formed by filing a132-in.flat on the sharpedge of the metal pattern and then carefully rounding the edgesformed by the132-in.flat and the sides of the wedge.If draft onthe pattern is desired,it may be obtained by varying dimensionH(Fig.1)from one end of the specimen to the other.Thepattern should be mounted in a core box so that the final corecan be poured with the wedge in such a position that its lengthis vertical.There shall be 1-in.(25.4-mm)minimum sand at thebottom of the core.4.Procedure4.1 CoresMake the test in a core.The cores may be eithersingle cores or gang cores.If a gang core is used,the minimumamount of sand between adjacent test specimens shall be notless than 212 B(Fig.1).The sand cores shall be well curedand free of moisture.The base sand shall be of such finenessthat a smooth casting will be obtained.A sand with an AFSfineness2of about 70 will be found satisfactory,although asand with a fineness of 100 or finer may be used for the smallertest specimens.4.2 Pouring PracticePour all samples at as consistent apouring temperature as possible since the amount of chill isclearly affected by the pouring temperature.Take precautionsto obtain a representative sample of iron for the test specimen.Best results are obtained with a sample ladle lined with arefractory mixture that is free of graphite and chilled iron.Theladle should hold at least 5 lb(2.3 kg)of iron in order to avoidexcessive chilling of the iron before the test specimen can bepoured.Filling the ladle once with iron just prior to obtainingthe sample for test is recommended.1These test methods are under the jurisdiction ofASTM Committee A04 on IronCastings and are the direct responsibility of Subcommittee A04.21 on Testing.Current edition approved July 1,2011.Published July 2011.Originally approvedin 1953.Last previous edition approved in 2005 as A367 60(2005).DOI:10.1520/A0367-11.2Mold&Core Test Handbook,The American Foundry SocietyCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.3 Cooling of Test SpecimenIf time is an important factorin control applications,the test specimen may be quenched inwater as soon as it is completely solid.The quenching must bedone carefully to avoid cracking of the chilled apex of thewedge.This may be accomplished by grasping the wedge withtongs at the apex of the wedge and immersing a