1、Designation: E473 16E473 18Standard Terminology Relating toThermal Analysis and Rheology1This standard is issued under the fixed designation E473; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number
2、in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This terminology is a compilation of definitions of terms used in ASTM documents relating to thermal analysis andrheology. This terminology in
3、cludes only those terms for which ASTM either has standards or is contemplating some action. It isnot intended to be an all-inclusive listing of terms related to thermal analysis and rheology.1.2 This terminology specifically supports the single-word form for terms using thermo as a prefix, such as
4、thermoanalyticalor thermomagnetometry, while recognizing that for some terms a two-word form can be used, such as thermal analysis. Thisterminology does not support, nor does it recommend, use of the grammatically incorrect, single-word form using thermal as aprefix, such as, thermalanalytical or th
5、ermalmagnetometry.1.3 A definition is a single sentence with additional information included in a Discussion area. It is reviewed every five years.1.4 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on P
6、rinciples for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2E1142 Terminology Relating to Thermophysical Properties3. Terminologyadiabatic, adjno heat
7、 exchange with the surroundings.calorimeter, napparatus for measuring quantities of absorbed or evolved bined, adjthe application of two or more techniques to different samples at the same time.controlled-rate thermal analysis (CRTA), na family of techniques that monitors the temperature versus time
8、 profile needed tomaintain a chosen, fixed rate of change of a property of a substance.DISCUSSIONCompared to controlled-temperature experiments, where the reaction rate tends to increase exponentially and the rate can become limited by heat ormass transfer, CRTA experiments are more likely to involv
9、e the chemical reaction as the limiting step. This technique can also improve the resolutionof multiple reactions. For example, in controlled rate experiments, power to the furnace is controlled to ensure a fixed rate of mass loss (or gain).controlled-temperature program, nthe temperature history ex
10、perienced by a sample during the course of a thermal analysisexperiment.DISCUSSIONIn contrast to controlled-rate experiments, power to the furnace is controlled to ensure a fixed rate of temperature change for controlled-temperature1 This terminology is under the jurisdiction of ASTM Committee E37 o
11、n Thermal Measurements and are the direct responsibility of Subcommittee E37.03 onNomenclature and Definitions.Current edition approved May 1, 2016Dec. 1, 2018. Published May 2016January 2018. Originally approved in 1973. Last previous edition approved in 20142016 asE473 14.E473 16. DOI: 10.1520/E04
12、73-16.10.1520/E0473-18.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard
13、and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases onl
14、y the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1experiments. The program may include heating or cooling segments in which the temperat
15、ure is changed at a fixed rate, isothermal segments in whichtime becomes the explicit independent variable, or any sequence of these individual segments. If the atmosphere (or vacuum) around the sample ischanged by some external action (depending on the independent variable onlytemperature or time)
16、during the course of the experiment, that toobecomes part of the controlled-temperature program.curve, thermal, nthe plot of a dependent parameter against an independent parameter such as temperature or time.derivative, adjpertaining to the first derivative (mathematical) of any curve with respect t
17、o temperature or time.dielectric analysis (DEA), na technique in which the dielectric constant (permittivity or capacitance) and dielectric loss(conductance) of a substance under oscillating electric field are measured as a function of temperature or time while thesubstance is subjected to a control
18、led-temperature program in a specified atmosphere.differential, adjpertaining to a difference in measured or measurable quantities usually between a substance and some referenceor standard material.differential scanning calorimetry (DSC), na technique in which the heat flow difference into a substan
19、ce and a referencematerial is measured as a function of temperature while the substance and reference material are subjected to acontrolled-temperature program.DISCUSSIONThe record is the differential scanning calorimetric or DSC curve. Two modes, power compensation differential scanning calorimetry
20、, and heat fluxdifferential scanning calorimetry can be distinguished, depending on the method of measurement used.DISCUSSIONTwo conventions exist in thermal analysis. In the physicists convention, exothermic behavior increases downward on the thermal curve. In thechemists convention, exothermic beh
21、avior increases upward on the thermal curve. Committee E37 takes no position on which convention shall beused. To aid the user, the direction of exothermic (or conversely, endothermic) behavior shall be indicated on each thermal curve.differential thermal analysis (DTA), na technique in which the te
22、mperature difference between the substance and a referencematerial is measured as a function of temperature, while the substance and reference material are subjected to acontrolled-temperature program.DISCUSSIONThe term quantitative differential thermal analysis covers those uses of DTA where the eq
23、uipment is designed to produce quantitative results.dilatometry, nsee thermodilatometry.dynamic mechanical analysis (DMA), na technique in which the storage modulus (elastic response) and loss modulus (viscousresponse) of a substance under oscillatory load is measured as a function of temperature, t
24、ime, or frequency of oscillation, whilethe substance is subjected to a controlled-temperature program in a specified atmosphere.electrobalance, nan analytical balance where the specimen weight is balanced by the torque produced by a current in a coil ina magnetic field (that is, a torque motor) with
25、 the torque proportional to the current.endotherm, nIn thermal analysis, the thermal record of a transition where heat is absorbed by the specimen.evolved gas analysis (EGA), na technique in which the nature or amount, or both, of gas or vapor evolved by a substance issubjected to a controlled-tempe
26、rature program.DISCUSSIONSome specific forms of EGA have become established for investigating different aspects of catalysis, such as reduction, oxidation, or desorption. Inthis context, EGA in a hydrogen atmosphere is known as temperature-programmed reduction (TPR); EGA in an oxygen atmosphere iste
27、mperature-programmed oxidation (TPO); and EGA in the absence of decomposition, in an inert atmosphere or vacuum, is temperature-programmeddesorption (TPD). For each technique the method used for gas identification and quantification should always be clearly stated.evolved gas detection (EGD), nsee e
28、volved gas analysis.extrapolated onset value, nthe value of the independent parameter found by extrapolating the dependent parameter baselineprior to the event and a tangent constructed at the inflection point on the leading edge to their intersection.first-deviation-from baseline, nthe value of the
29、 independent parameter at which a deflection is first observed from theestablished dependent parameter baseline prior to the event.E473 182high-pressure (HP.), adja prefix for different thermoanalytical techniques in which the pressure in the apparatus is aboveambient.DISCUSSIONAs an example, high-p
30、ressure thermogravimetric analysis is designated HPTGA.isoperibol, adjto maintain constant surroundings.DISCUSSIONFor calorimeters, if only the surroundings are isothermal, the mode of operation is isoperibol. In isoperibol calorimeters, the temperature changes withtime, governed by the thermal resi
31、stance between the calorimeter and surroundings.isothermal, adjat constant temperature.modulated temperature, adja prefix applied to the technique named to indicate that temperature modulation has been appliedto the temperature program.DISCUSSIONAs an example, a DSC experiment carried out with a mod
32、ulated temperature program would be Modulated Temperature Differential ScanningCalorimetry (MTDSC).DISCUSSIONOther modulated techniques are possible, such as modulated force TMA.DISCUSSIONThe use of the prefix MT is preferred to TM.nonreversing, adjin modulated temperature experiments, responding to
33、 the value of the temperature or time, or both.onset point (temperature or time), nthe temperature or time at which a deflection is first observed from the established baselineprior to the thermal event.peak, nthat portion of a thermal curve characterized by a deviation from the established baseline
34、, a maximum dependentparameter deflection, and a reestablishment of a baseline not necessarily identical to that before the peak.peak value, nthe value of the independent parameter corresponding to the maximum (or minimum) deflection from the baselineof the dependent parameter curve.plateau, na regi
35、on of little or no change in a graphical representation.pulse, na transient step-hold-return variation of a parameter that is normally constant where the intensity and duration arespecified.reversing, adjin modulated temperature experiments, responding to the rate of change of the temperature.rheome
36、ter, nan instrument for measuring rheological properties with a controlled temperature, shear rate, or stress program.rheometry, na technique in which viscosity, storage modulus, and loss modulus of a material are measured as a function oftemperature, time, shear rate, or stress while the material i
37、s subjected to controlled temperature, shear rate, or stress program.simultaneous, adjthe application of two or more techniques to the same sample at the same time.DISCUSSIONA hyphen is used to separate the abbreviations of the techniques; for example, simultaneous thermogravimetric analysis and dif
38、ferential scanningcalorimetry would be TGA-DSC.stochastic, adjrandom.E473 183tan , nis the dimensionless ratio of energy lost to energy returned during one cycle of a periodic process. Tan is normallycalculated by dividing the loss component of the property measured by a periodic method by the stora
39、ge component (forexample, tan = E”E as used in DMA).thermal analysis (TA), na group of techniques in which a physical property of a substance is measured as a function oftemperature or time while the substance is subjected to a controlled-temperature program.thermally stimulated current (TSC) analys
40、is, na technique in which the current generated when dipoles change their alignmentin a substance is measured as a function of temperature or time while the substance is subjected to a controlled-temperatureprogram in a specified atmosphere.DISCUSSIONThe technique can be applied in several ways: for
41、 example; the substance can be pre-conditioned by heating and cooling in a nonoscillating electricfield to create aligned, frozen dipoles. The substance may then generate a thermally stimulated current during subsequent heating with no field applied.thermoanalytical, adjof, or pertaining to, thermal
42、 analysis.thermodilatometry, na technique in which a dimension of a substance under negligible load is measured as a function oftemperature while the substance is subjected to a controlled-temperature program in a specified atmosphere.DISCUSSIONLinear thermodilatometry and volume thermodilatometry a
43、re distinguished on the basis of the dimension measured.thermogravimetric analysis (TGA), na technique in which the mass of a substance is measured as a function of temperatureor time while the substance is subjected to a controlled-temperature program in a specified atmosphere.DISCUSSIONThe record
44、is the thermogravimetric or TG curve.thermogravimetry (TG), nsee thermogravimetric analysis.thermomagnetometry, na family of thermoanalytical techniques in which a magnetic characteristic of a substance is measuredas a function of temperature or time while the substance is subjected to a controlled-
45、temperature program in a specifiedatmosphere.DISCUSSIONThermogravimetric analysis with a magnetic field acting on the specimen is the most common example.thermomechanical analysis (TMA), na technique in which the deformation of a substance under nonoscillatory load is measuredas a function of temper
46、ature or time while the substance is subjected to a controlled-temperature program in a specifiedatmosphere.DISCUSSIONThe load on the substance may be compressive, tensile, flexural, or torsional. When the applied load is too low to cause deformation, TMA measuresa dimension of the substance and in
47、this mode is called thermodilatometry.thermomicroscopy, nsee thermoptometry.thermoptometry, na family of techniques in which an optical characteristic of a substance is measured as a function oftemperature or time while the substance is subjected to a controlled-temperature program in a specified at
48、mosphere.DISCUSSIONMeasurement of total light, light of specific wavelength(s), refractive index, and luminescence leads, respectively, to thermophotometry,thermospectrometry, thermorefractometry, and thermoluminescence. Observations under the microscope lead to thermomicroscopy.valley, na region of
49、 minimum values in a graphical representation bordered by higher values.viscometer, nan instrument for measuring viscosity at fixed temperature, shear rate, or stress.viscometry, na technique in which viscosity of a material is measured at fixed temperature, shear rate, or stress.E473 184viscosity, rotational, na measure of viscosity (seeTerminology E1142) in which a rotational element (spindle) is unidirectionallyrotated in a measured fluid.4. Keywords4.1 definitions; rheology; terminology;
