1、Designation: D 4092 07Standard Terminology forPlastics: Dynamic Mechanical Properties1This standard is issued under the fixed designation D 4092; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number i
2、n parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This terminology is a compilation of definitions anddescript
3、ions of technical terms used in dynamic mechanicalproperty measurements on polymeric materials, including so-lutions, melts, and solids. Terms that are generally understoodor defined adequately in other readily available sources areeither not included or sources identified.1.2 A definition is a sing
4、le sentence with additional infor-mation included in notes. It is reviewed every five years andthe year of the last review or revision is appended.1.3 Definitions identical to those published by anotherstandards organization or ASTM committee are identified withthe abbreviation of the name of the or
5、ganization or the ASTMcommittee.1.4 Descriptions of terms specific to dynamic mechanicalmeasurements are identified with an italicized introductoryphrase.NOTE 1This terminology standard is similar to ISO 67211 however,the ISO document cites fewer terms.2. Referenced Documents2.1 ASTM Standards:2D 65
6、3 Terminology Relating to Soil, Rock, and ContainedFluidsD 883 Terminology Relating to PlasticsD 2231 Practice for Rubber Properties in Forced Vibration3E 6 Terminology Relating to Methods of Mechanical Test-ing2.2 ISO Standards:4ISO 472: 1988 (E/F) DefinitionsISO 67211 1994 (E) Plastics-Determinati
7、on of DynamicMechanical Properties, Part 1, General Principles3. Terminology Definitions and Descriptionsalpha (a) loss peak (in dynamic mechanical measurement)the first peak in the damping curve below the melt, in orderof decreasing temperature or increasing frequency. (1981)beta (b) loss peak (in
8、dynamic mechanical measurement)the second peak in the damping curve below the melt, inorder of decreasing temperature or increasing frequency.(1981)complex modulus, E*, K*, or G*the ratio of the stress tostrain where each is a vector that may be represented by acomplex number.E*=E8 + iE9G*=G8 + iG9K
9、*=K8 + iK9where:E* = complex modulus, measured in tension or flexure,E8 = storage modulus, measured in tension or flexure,E9 = loss modulus, measured in tension or flexure,G* = complex modulus, measured in shear,G8 = storage modulus, measured in shear,G9 = loss modulus, measured in shear,K* = comple
10、x modulus, measured in compression,K8 = storage modulus, measured in compressionK9 = loss modulus, measured in compression, andi=1 , measured in compression.DISCUSSIONThe complex modulus may be measured in tension (E*), compression (K*), flexure ( E*), or in shear (G*). (1981)complex shear complianc
11、e, J *the reciprocal of complexshear modulus. (1981)J* 51G*complex tensile compliance, D*the reciprocal of complextensile modulus. (1981)D* 51E*critical damping (in dynamic mechanical measurement)thatdamping required for the borderline condition betweenoscillatory and nonoscillatory behavior. (1983)
12、.dampingthe loss in energy, dissipated as heat, that resultswhen a material or material system is subjected to anoscillatory load or displacement. (1981)1This terminology is under the jurisdiction ofASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.10 on Mechanical P
13、roperties.Current edition approved March 1, 2007. Published March 2007. Originallyapproved in 1982. Last previous edition approved in 2001 as D 4092 - 01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMS
14、tandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1*A Summary of Changes section appears at the end of this standard.Co
15、pyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.damping ratio, the ratio of actual damping to criticaldamping. (1983).DISCUSSIONDamping ratio is a function of the logarithmic decre-ment (D): 5D/2p=1 1 D/2p!25 sin arctan D/2p!For small v
16、alues of D,itis:=D/2pdissipation factor see tan delta.dynamic mechanical measurementa technique in whicheither the modulus or damping, or both, of a substance underoscillatory load or displacement is measured as a function oftemperature, frequency, or time, or combination thereof.(1981)dynamic modul
17、ussee complex modulus.elasticitythat property of materials that causes them to returnto their original form or condition after the applied force isremoved. (1981)elastic modulussee complex modulus and storage modu-lus.energy lossthe energy per unit volume that is lost in eachdeformation cycle. (ISO)
18、 (1983)DISCUSSIONEnergy loss is the hysteresis loop area, calculated withreference to coordinate scales.free vibration (in dynamic mechanical measurement)a tech-nique for performing dynamic mechanical measurements inwhich the sample is deformed, released, and allowed tooscillate freely at the system
19、s natural resonant frequency.DISCUSSIONElastic modulus is calculated from the measured reso-nant frequency, and damping is calculated from the rate at which theamplitude of the oscillation decays. (1981)frequency profile , na plot of the dynamic properties of amaterial, at a constant temperature, as
20、 a function of testfrequency. (1981)gamma (g) loss peak , nthe third peak in the damping curvebelow the melt, in the order of decreasing temperature orincreasing frequency. (1981)glass transitionthe reversible change in amorphous poly-mer, or in amorphous regions of a partially crystallinepolymer, f
21、rom (or to) a viscous or rubbery condition to (orfrom) a hard and relatively brittle one.DISCUSSIONThe glass transition generally occurs over a relativelynarrow temperature region and is similar to the solidification of a liquidto a glassy state; it is not a phase transition. Not only do hardness an
22、dbrittleness undergo rapid changes in this temperature region, but otherproperties, such as coefficient of thermal expansion and specific heat,also change rapidly. This phenomenon has been called second-ordertransition, rubber transition, and rubbery transition. The word transfor-mation has also bee
23、n used instead of transition. When more than oneamorphous transition occurs in a polymer, the one associated withsegmental motions of the polymer backbone chain, or accompanied bythe largest change in properties, is usually considered to be the glasstransition. (D20) (1981)glass transition temperatu
24、re, Tgthe approximate midpointof the temperature range over which the glass transitiontakes place.DISCUSSIONThe glass transition temperature can be determinedreadily only by observing the temperature at which a significant changetakes place in a specific electrical, mechanical, or other physicalprop
25、erty. Moreover, the observed temperature can vary significantly,depending on the specific property chosen for observation and ondetails of the experimental technique (for example, rate of heating,frequency). Therefore, the observed Tgshould be considered only anestimate. The most reliable estimates
26、are normally obtained from theloss peak observed in dynamic mechanical tests or from dilatometricdata. (D20) (1981)hysteresis loop (in dynamic mechanical measurement)theclosed curve representing successive stress-strain status ofthe material during a cyclic deformation. (ISO) (1983)DISCUSSIONHystere
27、sis loops may be centered around the origin ofcoordinates or, more frequently, displaced to various levels of strain orstress; in this case, the shape of the loop becomes variously asymmetri-cal, but this fact is frequently disregarded.logarithmic decrement, D (in dynamic mechanicalmeasurement)the n
28、atural logarithm of the ratio of any two(or more) successive amplitudes of like sign, in the decay ofsingle frequency oscillation:D51klnAnAn 1 kwhere: Anand An+kare amplitudes (in radians of rotation) oftwo oscillations, and k is the number of oscillations separatingthe two amplitude measurements. (
29、1981)loss angle, d see phase angle.loss factorsee tan d.loss modulusM9(Pa)loss compliance O9 (Pa1): theimaginary part of the complex modulus (compliance).DISCUSSIONIt is a measure of the energy lost (dissipated during aloading cycle). (See also complex modulus and complex compliance.)(See ISO 67211.
30、)loss tangentsee tan delta.mean modulusthe ratio of mean stress to mean strain. (ISO)(1983)mean strainthe average value of strain during a singlecomplete hysteresis loop of cyclic deformation. (ISO) (1983)mean stressthe average value of the stress during a singlecomplete hysteresis loop of cyclic de
31、formation. (ISO) (1983)modulus, complexsee complex modulus.modulus, elasticsee complex modulus and storage modu-lus.modulus, losssee complex modulus and loss modulus.modulus, storagesee complex modulus and storage modu-lus.modulus of elasticity see complex modulus and storagemodulus.nonresonant forc
32、ed and vibration technique , na tech-nique for performing dynamic mechanical measurements, inwhich the sample is oscillated mechanically at a fixedfrequency.DISCUSSIONStorage modulus and damping are calculated from theapplied strain and the resultant stress and shift in phase angle. (1981)normal str
33、ess, sthe stress component perpendicular to aplane on which the forces act. (E28) (1981)phase angle, dthe angle between a sinusoidally appliedstrain and the resultant sinusoidal stress. (1981)D4092072Poissons ratio, nthe absolute value of the ratio of trans-verse strain to the corresponding axial st
34、rain resulting fromuniformly distributed axial stress below the proportionallimit of the material.DISCUSSIONPoissons ratio will have more than one value if thematerial is anisotropic. (E-28) (1981)power lossthe power, per unit volume, that is transformedinto heat through hysteresis. (ISO) (1983)DISC
35、USSIONPower loss is the product of energy loss and frequency.quality factor, Qthe ratio of elastic modulus to loss modu-lus, measured in tension, compression, flexure, or shear.DISCUSSIONThe quality factor is a nondimensional term. Thequality factor is the reciprocal of tan delta. (1981)relative rig
36、idity (in dynamic mechanical measurement)theratio of modulus at any temperature, frequency, or time tothe modulus at a reference temperature, frequency, or time.(1981)resonant forced vibration technique (in dynamic mechanicalmeasurement)a technique for performing dynamic me-chanical measurements, in
37、 which the sample is oscillatedmechanically at the systems natural resonant frequency.DISCUSSIONThe amplitude of oscillation is maintained constantthrough the addition of makeup energy. Elastic modulus is calculatedfrom the measured frequency. Damping is calculated from the addi-tional energy requir
38、ed to maintain constant amplitude. (1981)rootmeansquare strainthe square root of the mean valueof the square of the strain, averaged over one cycle ofdeformation. (ISO) (1983).DISCUSSIONFor a symmetrical sinusoidal strain, the root-mean-square strain equals the strain amplitude divided by = 2.rootme
39、ansquare stressthe square root of the mean valueof the square of the stress, averaged over one cycle ofdeformation. (ISO) (1983)DISCUSSIONFor a symmetrical sinusoidal stress, the root-mean-square stress equals the stress amplitude divided by = 2.shearan action or stress, resulting from applied force
40、s,which causes (or tends to cause) two contiguous parts of abody to slide, relative to each other, in a direction parallel totheir plane of contact. (1981)shear modulus, G (Pa)the quotient of shear stress and shearstrain. (See ISO 537.)G 5sgshear rate, gthe time rate of change of shear strain. For a
41、one-dimensional shear flow, it is the velocity gradient.(1981)shear strain, gthe tangent of the angular change, due toforce, between two lines originally perpendicular to eachother through a point in a body. (E-28) (1981)shear stress, tthe stress component tangential to the planeon which forces act.
42、 (E-28) (1981)storage compliance, C (Pa1)the quotient of strain andstress.C 5es51Mwhere: D is the tensile compliance; J is the shear compli-ance; C is the storage compliance; and M is the storagemodulus.storage modulusM* (Pa), storage compliance C (Pa1)the real part of the complex modulus (complex c
43、ompliance).DISCUSSIONIt is a measure of the energy stored and retained duringa loading cycle. (See also complex modulus and complex compli-ance.) (See ISO 67211.)strain, ethe unit change, due to force, in the size or shape ofa body referred to its original size or shape.DISCUSSIONStrain at a point i
44、s defined by six components of strain:three normal components and three shear components, referred to a setof coordinate axes. With appropriate rotation of coordinate axis, thestrain may be fully described by three normal components alone. (E-28)(1981)strain amplitudethe ratio of the maximum deforma
45、tion,measured from the mean deformation, to the free length ofthe unstrained test specimen. (ISO) (1983)DISCUSSIONStrain amplitude is measured zero to peak on one sideonly.stress, sthe intensity at a point in a body of the internalforces or components of force that act on a given planethrough the po
46、int. (E-28) (1981)stress amplitudethe ratio of the maximum applied force,measured from the mean force, to the cross-sectional area ofthe unstressed test specimen. (ISO) (1983)tan delta, tan dthe ratio of the loss modulus to the storagemodulus, measured in compression, tension, flexure, orshear. (198
47、1)Tan d5K9K85E9E85G9G8time profilea plot of the modulus or damping, or both of amaterial versus time. (1981)torsional penduluma device for performing dynamic me-chanical analysis, in which the sample is deformed torsion-ally and allowed to oscillate in free vibration.DISCUSSIONModulus is determined
48、by the frequency of the resultantoscillation, and damping is determined by the decreasing amplitude ofthe oscillation. (1981)torsional stressthe shear stress on a transverse cross section,resulting from a twisting action. (E-28) (1981)viscosity, hthe property of resistance to steady flow exhib-ited
49、within the body of the material.DISCUSSIONIn determining the ratio of the shearing stress to the rateof shear of a fluid, viscosity is usually taken to mean “NewtonianViscosity”, in which case the ratio of shearing stress to the rate ofshearing strain is constant. In non-Newtonian behavior, which is theusual case with plastic materials, the ratio varies with the shearing rate.Such ratios are often called the “Apparent Viscosity” at the correspond-ing shear rate. (D20) (1981)visc
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