ASTM_B_223_-_08_2013.pdf

Designation:B22308(Reapproved 2013)Standard Test Method forModulus of Elasticity of Thermostat Metals(CantileverBeam Method)1This standard is issued under the fixed designation B223;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 This test method covers the determination of the modu-lus of elasticity of thermostat metals at any temperaturebetween 300 and+1000F(185 and 540C)by mounting thespecimen as a cantilever beam and measuring the deflectionwhen subjected to a mechanical load.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.1.3 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 become familiarwith all hazards including those identified in the appropriateMaterial Safety Data Sheet(MSDS)for this product/materialas provided by the manufacturer,to establish appropriatesafety and health practices,and determine the applicability ofregulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2B388 Specification for Thermostat Metal Sheet and Strip3.Terminology3.1 Definitions:3.1.1 thermostat metal,na composite material,usually inthe form of sheet or strip,comprising two or more materials ofany appropriate nature,metallic or otherwise,which,by virtueof the differing expansivities of the components,tends to alterits curvature when its temperature is changed.3.1.2 modulus of elasticity,nthe ratio,within the elasticlimit of a material,of stress to corresponding strain.In this testmethod the modulus of elasticity is calculated from theexpression for the deflection of a cantilever beam undermechanical load which is transposed to read as follows:E 5 4Pl3/dbt3where:E=modulus of elasticity,psi or MPa,P=load,lbf or N,l=gage length,in.or mm,d=specimen deflection,in.or mm,b=specimen width,in.or mm,andt=specimen thickness,in.or mm.4.Apparatus(Figs.1-3)4.1 Specimen Holder for securely clamping the test speci-men in a horizontal position as a cantilever beam whenimmersed in a bath at the desired temperature.It shall carry amicrometer depth gage for reading the deflection of thespecimen and a loading rod for loading the specimen.Both ofthese shall extend sufficiently above the liquid level of the bathto permit the operator to perform the test at the higher testtemperatures.4.1.1 Specimen holder to be made sufficiently rigid to allownormal handling without distortion.4.2 Loading Rod,18in.(3.2 mm)or less in diameter,forcarrying the load and transmitting its weight vertically to thefree end of the cantilever specimen.It shall be made of a lowexpansion material;the mounting clamp and tube shall bemade of the same material as the specimen mounting clamps inorder to prevent a difference in expansion rates from affectingthe deflection readings.The bottom end shall be conicallyshaped and shall rest in the conical punch mark at the free endof the specimen.Any supports shall permit free movement withspecimen deflection and shall provide electrical insulation fromthe micrometer depth gage.Near the top shall be a holder forsupporting the load.The weight of the loading rod and holdershall be no greater than 1 oz(28 g).4.3 Micrometer Depth Gage,for measuring the deflection ofthe specimen to the nearest 0.0001 in.(0.002 mm).It shall bemounted directly over the loading rod.The micrometer shaftshall be in the same vertical line as the loading rod,so thatreadings can be taken of the top of the loading rod for no-load1This test method is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.10 on Thermostat Metals and Electrical Resistance Heating Materials.Current edition approved Aug.1,2013.Published August 2013.Originallyapproved in 1948.Last previous edition approved in 2008 as B223 08.DOI:10.1520/B0223-08R13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 and full-load positions.The gage shall be insulated electricallyfrom the specimen holder and the loading rod.4.4 Load,constructed so that when placed in the holder,itscenter of gravity will coincide with the center of the loadingrod.It shall be readily detachable for the operators conve-nience in taking no-load and full-load readings and shall not beof sufficient weight to deflect the specimen m