ASTM_B_388_-_06_2012.pdf

Designation:B38806(Reapproved 2012)Standard Specification forThermostat Metal Sheet and Strip1This standard is issued under the fixed designation B388;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 specification covers thermostat metals in the formof sheet or strip that are used for the temperature-sensitiveelements of devices for controlling,compensating,or indicat-ing temperature and is intended to supply acceptance require-ments to purchasers ordering this material by type designation.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:2B63 Test Method for Resistivity of Metallically ConductingResistance and Contact MaterialsB106 Test Methods for Flexivity of Thermostat MetalsB223 Test Method for Modulus of Elasticity of ThermostatMetals(Cantilever Beam Method)B362 Test Method for Mechanical Torque Rate of SpiralCoils of Thermostat MetalB389 Test Method for Thermal Deflection Rate of Spiral andHelical Coils of Thermostat MetalB478 Test Method for Cross Curvature of Thermostat MetalsB753 Specification for Thermostat Component AlloysC351 Test Method for Mean Specific Heat of ThermalInsulation(Withdrawn 2008)3E92 Test Method for Vickers Hardness of Metallic Materials(Withdrawn 2010)3E384 Test Method for Knoop and Vickers Hardness ofMaterials3.Terminology3.1 Definitions:3.1.1 thermostat metal,na composite material comprisingtwo or more metallic layers of differing coefficients of thermalexpansion such that the radius of curvature of the compositechanges with temperature change.4.Ordering Information4.1 Orders for material under this specification shall includethe following information:4.1.1 Type designation(Table 1 and Table 2),4.1.2 Thickness(see 9.1),4.1.3 Width(see 9.2),4.1.4 Temper(designated as percent cold reduction asneeded),4.1.5 Marking to identify vendor,type,high-expansion sideor low-expansion side,4.1.6 Weight.5.Material Segregation5.1 The thermostat metal shall be supplied segregated intotwo groups after slitting:(1)the burr on the low-expansivecomponent,and(2)the burr on the high-expansive component.These two groups shall be identified and packaged separatelyor together as mutually agreed upon between the producer andthe user.6.Chemical Composition6.1 The nominal composition of component materials isgiven in Table 1.6.1.1 The component alloys shall be as specified in Speci-fication B753.7.Component Ratio7.1 The typical thickness ratio of the component materials isgiven in Table 1.The component thickness ratios are given for1This specification 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 May 1,2012.Published May 2012.Originallyapproved in 1962.Last previous edition approved in 2006 as B388 06.DOI:10.1520/B0388-06R12.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 TABLE 1 CompositionNOTE1TM6 and TM7 are no longer manufactured due to availability,difficulty to produce,commercial interest,or combinations thereof.ASTM TypeElementTM1TM2TM3TM4TM5TM8TM9Nominal chemicalhigh-expansivenickel22102525251022composition,componentchromium3.8.58.58.5.3weight,%manganese.72.72.copper.18.18.iron75.66.566.566.5.75aluminum.carbon.intermediatecomponentnickelmanganese.100.low-expansivecomponentnickelironcobalt3664.3664.4258.4555.5050.3664.3664.Component ratio,thickness,%high-expansivecomponent50535050508027intermediatecomponent.46low-expansivecomponent50475050502027ASTM TypeElementTM10TM11TM12TM13TM14TM15TM16Nominal chemicalhigh-expansivenickel22222222222222composition,componentchromium3333333weight,%manganese.copper.iron75757575757575aluminum.carbon.intermediatecomponentnick