This standard specifies the terminology of material damping characteristics and gives definitions or explanations. This standard is applicable to describing the damping characteristics of homogeneous materials and their specimens under mechanical vibration and impact. The damping characteristics exhibited under other deformation conditions can also be used for reference. GB/T 14465-1993 Terminology of Material Damping Characteristics GB/T14465-1993 Standard download decompression password: www.bzxz.net
This standard specifies the terminology of material damping characteristics and gives definitions or explanations. This standard is applicable to describing the damping characteristics of homogeneous materials and their specimens under mechanical vibration and impact. The damping characteristics exhibited under other deformation conditions can also be used for reference.

National Standard of the People's Republic of China
Terms for specifying
damping properties of materials 1 Main content and applicable scope
This standard specifies the terms for damping properties of materials and gives definitions or explanations. GB/T 14465-93
This standard is applicable to describing the damping properties of homogeneous materials and their specimens under mechanical vibration and impact. The damping properties exhibited under other deformation conditions can also be used for reference. 2 General terms
2.1 Damping
The effect of dissipating the energy of a system during motion. 2.2 Damping force
The force that causes the system to dissipate energy during motion. 2.3 Homogeneous material
Material that is macroscopically uniform or macroscopically continuous. Including those materials with microscopic and submicroscopic interfaces, excluding materials with clearly visible interfaces between different parts.
2.4 Homogeneous specimens are specimens made of a single homogeneous material. Hysteresis loop
A closed curve representing the continuous stress-strain or force-displacement state of a material during periodic deformation. Its general shape is shown in the table below. is the material damping index.
Classification of hysteresis loops
Damping phenomenon related to deformation rate
Hysteresis loops have various shapes, but the ends are all
smooth
Hysteresis loops are elliptical
2.6 Instantaneous value of stress Approved by Guohao Technical Supervision Bureau on 1993-06-11 Hysteresis phenomenon related to strain amplitude
Hysteresis loops have various shapes, but the ends are all sharp Under medium stress -23, (2)
Under high force = 2 ~ 30
Implementation on 1994-03-01
The magnitude of a given instantaneous stress:
GB/T 14465—93
2. 6. 1f instantaneous value of bottom force (s) instantaneous yalue of normal stress The magnitude of a given instantaneous normal stress. 2.6.2 Instantaneous value of shear stress (r) instantaneous value of shear stress The minimum value of the stress at a given solution. [L-\MT-?-2.7 Amplitude of harmonic stress The maximum value of harmonic stress.
-N/m2]
2.7.1 Amplitude of harmonic narmal stress (a,) Amplitude of harmonic narmal stress The maximum value of harmonic normal stress. [L-\MT-2—--N/m2]
2.7.2 Amplitude of harmonic shear stress (t:) Amplitudinal value of harmonic shear stress The maximum value of harmonic shear stress, [I-MT-2N/m\]2.8 Instantaneous value of strain l sirain The magnitude of a given instantaneous strain.
2.8.1 Instantaneous value of linear strain () valuc of normal strain The magnitude of a given instantaneous linear strain,
2.8.2 Instantaneous valuc of shear strain (%) The magnitude of a given instantaneous shear strain
2.9 Amplitude of harmonic strain The maximum value of the simple harmonic strain,
2.9.1 Amplitude of harmonic strain (e,) Amplitudeofharmonicnormalsttain The maximum value of the simple harmonic strain.
2. 9.2 Amplitude of harmonic shear strain (%) The maximum value of the simple harmonic strain.
2.10 Modulus
Should be carefully compared with the corresponding strain.
2. 10.1 Modulus of elasticity (F) 2.10.2 Shear modulus (G) Shear modulus of elasticity The ratio of normal stress to linear strain.
2.11 Stiffness () The ratio of the increment of external force (torque) on an elastic body to the increment of displacement (rotation) produced by it. 2.11.1 Rectilinearstiffness The ratio of the increment of external force on an elastic body to the increment of displacement produced by it. [MT2—-N/m] 2.11.2 Torsional stiffness: The ratio of the increment of torque on an elastic body to the increment of rotation produced by it. L3MT-2——Nm/rad] 3 Damping characteristics terminology
3.1 Linear viscous damping The energy dissipation of a material or specimen caused by the internal damping force of the material whose magnitude is proportional to the deformation velocity and whose direction is opposite to the deformation velocity.
Synonyms Viscous damping
3.2 Nonlinear viscous damping Nonlinear viscous damping Energy dissipation of a material or a specimen caused by the internal damping force of the material which is proportional to the deformation velocity (not equal to "1") and opposite to the deformation velocity during vibration. CB/T 14465-93
3.3 Hysteretic damping When the vibration system is in simple harmonic vibration, the damping caused by the internal friction of the material, the energy dissipation of which in a fixed period is independent of the frequency and is proportional to the square of the amplitude.
Linear material Lincar material
Material with linear viscous damping characteristics. Its hysteresis loop is generally elliptical. 3.5 Single pseudo damping energy (D) unit camping energyThe energy consumed by the internal damping of a unit volume of homogeneous material under simple harmonic stress during a period of time. EL-IMT--J/(m.period)
The numerical value of the unit damping energy is proportional to the area of ​​the dynamic stress-strain hysteresis loop (see the figure below). R -EAY
Generally:
hysteresis loop and its characteristics
D= 4ade
For simple vibration with frequency of, the unit damping energy is: a(ar)d(t) =
Formula: t-
time.
For linear materials under normal stress:
([de()/dtdt
Formula: E\…loss elastic modulus.
3.6 Damping energy of specimen (D.)specitren rdamping energy(l
Energy dissipated by the damping force in the material under the action of simple harmonic load in a homogeneous specimen in a cycle. [L\MT\--cycle
Obtained by integrating the unit damping energy over the specimen volume. 3.7 Unit strain energy (U) unil strainl energyGB/T 14465-93
The strain energy stored in a unit volume of homogeneous material under simple harmonic stress in a cycle. [L-\MT-2phase
For linear materials, the unit strain energy is:
Where: The elastic energy storage mold, that is, the area between the positive and negative lines Ob and the horizontal axis in the above figure. 3.8 Specimen strain energy (U) specimen strain energyThe strain energy stored in a homogeneous specimen under simple harmonic load in a cycle. [L*MT-J/cycle 3.9 Specific damping capacityThe ratio of unit damping energy to unit strain energy. D
3-10Complex modulus of elasticity (E+)Complex modulus of elasticityThe elastic modulus expressed in complex form. [L-\MT-——N/m］]E* = E' +iE\
Storage modulus of elasticity (E\)storage modulua of elasticity3.11
Real part of the complex elastic modulus. [L-iMT-—N/m”] 3.12 Loss modulus (E\) Loss modulus of elasticity The random part of the complex elastic modulus. EL-IMT-2—N/m\ 3.13 Absolute value of complex modulus of elasticity (/E*1) absolute value of complex modulus of elasticity The modulus of complex elastic modulus. [L-\MT-\
-N/m2]
[E= (E +E\)2
3.14 Complex shear modulus (G) complexshearmodulusofelasticity The shear modulus expressed in complex form. [LMT-2—N/mG. -G' +iG\
3.15 Storage shear modulus (G) storageshearmodulusofelasticity The real part of the complex shear modulus. [L-IMT-—
3.16 Loss shear modulus (G\) lossshearmodulus of elasticityJm\·周
(4))
The real part of the complex shear modulus. [L-\MT-2——N/m Absolute value of complex shear modulus ([G*) absolute value of complex shear modulus af elasticity3. 17
The modulus of complex shear modulus,
IG -(G +Greyu2
3.18 Complex stiffness (k*) complexstiffneg9 Stiffness expressed in complex form.
+( 10 3
GB/T 14465—93
3. 18. 1 Complex rectilinear stiffness
Complex rectilinear stiffness The rectilinear stiffness expressed in complex form. [MT-2——N/m] 3.18-2
Complex torsional stiffness The torsional stiffness expressed in complex form, [L\MT·2—3. 19 Storage stiffness (n) storage stiffness The real part of the complex stiffness.
3.20 Consumption stiffness (\) lass stiffnes8 The random part of the complex stiffness.
-N + m/radl
Absolute value of complex stiffness (|[) Absolute value of complex stiffness The modulus of the complex stiffness.
[k*| =( +)1/2
2 Linear viscous damping coefficient (C) linear viscousdamping coefficient3.22
The ratio of the linear viscous damping force to the deformation velocity. "MT-1.3.23 Critical damping coefficient (C) criticaldamping coellicientN-s/m
The minimum linear viscous damping coefficient that allows a single-degree-of-freedom system that deviates from the equilibrium position to return to the equilibrium position without vibration. [MT-1
-N*x/tm3
C, = 2(m - )1/7
Where: m——-mass of the system +
—stiffness of the system.
3.24 Damping ratio () dampirg ratio
The ratio of the linear viscous damping coefficient to the critical damping coefficient. r= CC
3.25 Quality factor quality factor
A measure of the sharpness of the resonance of a single-degree-of-freedom system. 3.25.1 Quality factor of a material (Q) Quality factor for a material Proportional to the ratio of unit strain energy to unit damping energy. 2x
3.25.2 Quality factor of a specimen (Q.) Quality factor far a uniform specification Proportional to the ratio of strain energy to damping energy of the specimen. Q
3.26 Loss factor
Luss factor
(12)
(13)
(15)
GB/T14465-93
A measure of the energy dissipation capacity of a material or specimen. 3.26.1 Loss factor of a material (9) Loss factor of a material A measure of the energy dissipation capacity of a material. Its value is proportional to the ratio of unit damping energy to unit strain energy. B
3.26.2 loss factor of a uniform specimen (9.) loss factor of a uniform specimen The value of the energy dissipation capacity of the specimen. Its value is proportional to the ratio of the specimen damping energy to the specimen strain energy. p.
loss angle ()loss angle
The phase difference between strain and stress in vibration. 3.28 loss angle tangent (tane) loss 1angent The tangent of the loss angle.
3.29 Logarithmic decrement (logarithmicdecrementD
Natural logarithm of the ratio of two consecutive amplitudes in a single-frequency decay vibration 4
Where: X., X+
Amplitudes of the nth and n+1th vibration cycles, synonyms logarithmic reduction rate
3. 30 Damping constant of a material (J) damping constant of a material! When the unit damping energy can be expressed by =Jann, it is the material damping constant. [(M1.-1T\)\e3.31 Damping exponent of a material (n) damping exponent of a material When the unit damping energy can be expressed by L), it is the material damping exponent. (16)
(N/m)-)
Material quality factor
Material loss factor.
Material damping constant
Material damping index
Storage shear modulus
Storage stiffness
Storage elastic modulus
Hysteresis damping
Unit strain energy
Unit damping energy
Logarithmic decay rate
Nonlinear viscous damping
Complex stiffness
Complexity Absolute value
Complex tension and compression stiffness
Complex torsional stiffness·
Complex shear modulus
Absolute value of complex shear modulus:
Complex elastic modulus
Absolute value of complex elastic modulus·
Harmonic shear strain amplitude
Harmonic shear strain amplitude
Harmonic linear strain amplitude
Harmonic strain amplitude
Harmonic stress amplitude
Harmonic stress amplitude
Homogeneous material
GB/T 14465
Appendix A
Chinese index
(Supplement)
Homogeneous specimen
Tensile and compressive stiffness
Critical Yinni coefficient
3.11 Modulus -
Torsional stiffness·
- 2. 7. 2
Quality factor
Shear modulus·
Instantaneous value of shear strain
Instantaneous value of shear stress
Effective shear modulus
Loss elastic modulus
Loss stiffness·
Loss angle
Loss tangent·
Loss factor:www.bzxz.net
Quality factor of specimen
Loss factor of specimen
Specimen strain energy
Specimen damping energy
Elastic modulus
Linear material
Linear viscous damping
. 3.12
Linear viscous damping coefficient.
Instantaneous value of linear strain
Strain value
Instantaneous stress
GB/T 1446593
damping ratio
damping specific capacity
instantaneous value of normal stress
Appendix B
English inspection
(supplement)
absolute value of complex modulus of elasticityabsolute value of romplex shear modulus of elasticityabsolute yalue of complex stiffnessr:amplitude of harmonic normal stressamplitude of harmonic shear stressamplitude of harmonic stressapliturle μl harnionic normal strainamplitude of harmonic shear strainamplitude of harmonic strain++++
complex madulus of elasticitycomplex rectilinear stiffnesscomplcx shcar modulus of elasticitycomplex stiffness
complex torsional stiffness||tt ||critical damping coefficientD
damping .
damping constant of a materialdamping exponent of a materialdamping force
damping ratio
hysteresis loop
hystcreticdamping||tt ||instantaneous value of normal stainZ
*** 3.18. 2
instantaneous value of shear stain.instantaneous value of siraininstantaneous value of normal stress ..inntantaneous value ol shear stressinstantaneus value of stressJinear material
linear viscos damping
linear viscos darnping coefficientlogarithmic decrement
loss atigle *+
loss factor
lass factor of a material
loss factor of a unifarm specimenloss modulus of elasticity
loss shear modulus of elasticityloss $tiflness
loss tangent
modulus
modulus of elasticity
non-linear viscous dsmping
qualityfactor
quality factor for a materialquality factor for a uniform specimenrcetilinear stiffnest
shear modulus of elasticity
specific damping capacity
specimen damping erergy
specimen strain energy
stiffness
storagt modulus of elasticitystorage shear modulus of elasticityGB/T 14465--93
+ 3. 26.2
..3.25.1
storage stiffnes
torsional stiffness
uniform material
uniform specimer
unit damping energy||tt ||unit strain energy
Additional remarks:
GB/T 14465--93
This standard was proposed by the Ministry of Aerospace Industry of the People's Republic of China. This standard is drafted by the 72nd Institute of the Ministry of Aerospace Industry. The main drafter of this standard is Li Hong.inntantaneous value ol shear stressinstantaneus value of stressJinear material
linear viscos damping
linear viscos darnping coefficientlogarithmic decrement
loss atigle *+
loss factor
lass factor of a material
loss factor of a unifarm specimenloss modulus of elasticity
loss shear modulus of elasticityloss $tiflness
loss tangent
modulus
modulus of elasticity
non-linear viscous dsmping
qualityfactor
quality factor for a materialquality factor for a uniform specimenrcetilinear stiffnest
shear modulus of elasticity
specific damping capacity
specimen damping erergy
specimen strain energy
stiffness
storagt modulus of elasticitystorage shear modulus of elasticityGB/T 14465--93
+ 3. 26.2
..3.25.1
storage stiffnes
torsional stiffness
uniform material
uniform specimer
unit damping energy||tt ||unit strain energy
Additional remarks:
GB/T 14465--93
This standard was proposed by the Ministry of Aerospace Industry of the People's Republic of China. This standard is drafted by the 72nd Institute of the Ministry of Aerospace Industry. The main drafter of this standard is Li Hong.inntantaneous value ol shear stressinstantaneus value of stressJinear material
linear viscos damping
linear viscos darnping coefficientlogarithmic decrement
loss atigle *+
loss factor
lass factor of a material
loss factor of a unifarm specimenloss modulus of elasticity
loss shear modulus of elasticityloss $tiflness
loss tangent
modulus
modulus of elasticity
non-linear viscous dsmping
qualityfactor
quality factor for a materialquality factor for a uniform specimenrcetilinear stiffnest
shear modulus of elasticity
specific damping capacity
specimen damping erergy
specimen strain energy
stiffness
storagt modulus of elasticitystorage shear modulus of elasticityGB/T 14465--93
+ 3. 26.2
..3.25.1
storage stiffnes
torsional stiffness
uniform material
uniform specimer
unit damping energy||tt ||unit strain energy
Additional remarks:
GB/T 14465--93
This standard was proposed by the Ministry of Aerospace Industry of the People's Republic of China. This standard is drafted by the 72nd Institute of the Ministry of Aerospace Industry. The main drafter of this standard is Li Hong.
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