On the possibilities of application of thermal wave methods for standardized measurement of thermal diffusivity

Transcription

1 13 TH Winter Workshop on PA & TWM, Wisła 008 On the possibilities of application of thermal wave methods for standardized measurement of thermal diffusivity Jerzy Bodzenta, Jacek Mazur *, Barbara Pustelny Silesian University of Technology, Institute of Physics * jacek.mazur@polsl.pl 1

2 Determination of thermal properties Outline Standardized methods quick review Methods for determination of thermal diffusivity of plate Flash method (standardized) Thermal wave methods Possible configurations of measurement set-up Examples Properties of Two-beam method Conclusions

3 Determination of thermal properties (1) Description of thermal properties thermal conductivity specific heat heat capacity thermal diffusivity thermal effusivity thermal resistance κ c C W [ m K ] J kg K = ρc κ α = C ε = κc R Q d = κ J 3 m K m s m K W W s m K Basic laws Fourier s law r j Q = κ r T basic equation of constantvolume calorimetry dq = mcdt = CVdT Fourier-Kirchhoff equation 1 T q T = α t κ 3

4 Determination of thermal properties () Steady flux methods r j = κ r T Q Variable flux methods r r ( ) T r κ T = C q α T = t T t Absolute Comparative Pulse Transient Wave Guarded-Hot-Plate Method Guarded-Comparative- Longitudinal Heat Flow Technique Flash method Hot-wire method Ångström s methods Heat-Flow-Meter Technique TTG method Interference methods 3ω method Comparative methods 4

5 ABSOLUTE Guarded-Hot-Plate Method STEADY FLUX METHODS ISO 007-: Plastics - Determination of thermal conductivity and thermal diffusivity - Part : Transient plane heat source (hot disk) method ASTM: C Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded- Hot-Plate Apparatus ISO: 830:1991 Thermal Insulation Determination of Steady-State Thermal Resistance and Related Properties Guarded Hot Plate Apparatus Heat-Flow-Meter Technique C Standard Test Method for Steady-State Thermal Transmission Properties by Means of the Heat Flow Meter Technique ASTM: E Standard Test Method for Evaluating the Resistance to Thermal Transmission of Materials by the Guarded Heat Flow Meter Technique COMPARATIVE Guarded-Comparative- Longitudinal Heat Flow Technique ASTM: E15-04 Standard Test Method for Thermal Conductivity of Solids by Means of the Guarded-Comparative-Longitudinal Heat Flow Technique 5

6 VARIABLE FLUX METHODS (1) PULSE METHODS Laser Flash (Heat Pulse) ASTM E Standard Test Method For Thermal Diffusivity of Solids By The Flash Method ISO Fine Ceramics (Advanced Ceramics, Advanced Technical Ceramics) - Determination Of Thermal Diffusivity Of Monolithic Ceramics By Laser Flash Method ISO DIS Plastics - Determination Of Thermal Conductivity And Thermal Diffusivity - Part 4: Laser Flash Method BS 7134 P4 S4. Testing Of Engineering Ceramics - Thermo- Mechanical Properties - Method For The Determination Of Thermal Diffusivity, By The Laser Flash (Or Heat Pulse) Method BS EN 81- Advanced Technical Ceramics - Monolithic Ceramics - Thermo- Physical Properties - Part. Determination Of Thermal Diffusivityby The Laser Flash (Or Heat Pulse) Method JIS R 1667 Determination Of Thermal Diffusivity Of Continuous Fiber- Reinforced Ceramic Matrix Composites By The Laser Flash Method JIS R 1611 Test Methods Of Thermal Diffusivity, Specific Heat Capacity, And Thermal Conductivity For Fine Ceramics By Laser Flash Method 6

7 PULSE METHODS VARIABLE FLUX METHODS () Laser Flash (Heat Pulse) cont. *PL, BS, DIN EN 81 P Monolithic Ceramics - Thermo-Physical Properties - Part. Determination Of Thermal Diffusivity By The Laser Flash (Or Heat Pulse) Method *PL, DIN EN Advanced Technical Ceramics - Ceramic Composites; Thermophysical Properties - Part : Determination Of Thermal Diffusivity (Foreign Standard) * Translated to Polish TRANSIENT Hot-wire method WAVE ISO 8894-:007 Refractory materials - Determination of Thermal Conductivity Part : Hot-wire method Ångström's Method ISO/DIS 007-3: Plastics - Determination of Thermal Conductivity and Diffusivity - Part 3: Temperature wave analysis method Under Development 7

8 WAVE Thermal Wave Method VARIABLE FLUX METHODS (3) DIN 5099-: Determination of the layer thickness Under Development? 8

9 Thermal diffusivity flash (1) T Q n n π αt ( t ) T ( L, t ) = 1 + ( 1) exp = ρcl n=1 L IR Detektor Tlim T(L,t) Sample Optics Pulse Laser / Flash Lamp Parker et al., Flash Method of Determining Thermal Diffusivity, Heat Capacity and Thermal Conductivity, J. Appl. Phys., 3(9),

10 Thermal diffusivity flash () ( L, t ) V = T T ( L, t ) lim V V n ( ) ( ) ( L, t = 1+ 1 exp n ) n= 1 ω ω 10 ω = π αt L α = L 0.48 π t x L α = 1.38 π t 0,5 Standardized method: EN

11 Pulse, thermal wave comparison (1) Method Pulse Thermal wave Domain of measurement: Time Amplitude vs. time Frequency Phase vs. frequency Generation of heat source: Light puls Laser / Flash Lamp Modulate light Temperature detection Thermocouple, IR radiometry, PA cell IR radiometry, PA cell, Optical photodeflection, reflection Common characteristic time: 11

12 Pulse, thermal wave comparison () Equivalence of two measurement techniques: CW laser with mechanical chopper Pulsed laser (5ns, 6.3mJ) + FFT A.I. Korobov, N.I. Odina, I.N. Kokshaysky and A.F. Asainov, Pulsed Photoacoustic Technique for Thermal Diffusivity Determination, IEEE Ultrasonic Symposium 1994, p

13 TWM Set-up Sample Detector (IR or PA) Light Source (Back) Light source (Front) Control Unit (PC) Measurement Data Acquisition 13

14 Front illumination TWM configurations Thermal wave interference Comparative method e.g. carbon black thermally thick reference sample Back illumination Flash method equivalent Reference sample needed Both sides illumination (Two-beam method) Self-normalized method Simplified fitting procedure 14

15 Two-beam method - examples (1) T. Sheenu, I. Johney J. Philip, Thermal diffusivity of solids by photoacoustic cell rotation and phase lag measurement, Rev. Sci. Instrum., 66 (7), 1996, 3907 M. Aravind, P. C. W. Fung, S. Y. Tang, and H. L. Tam, Two-beam photoacoustic phase measurement of the thermal diffusivity of a Gd-doped bulk YBCO superconductor, Rev. Sci. Instrum., 67(4), 1996 J.A. Balderas-Lopez, Photothermal signal normalization method and its application to the measurement of the thermal diffusivity for opticaly opaque materials, Rev. Sci. Instrum., 77, 06490, 006 O. Pessoa,Jr, C.L. Cesar, N.A. Patala, H. Vargas, C.C. Ghizoni and L.C.M. Miranda, Two beam photoacoustic phase measurement of the thermal diffusivity of solids, J. Appl. Phys. 59(4), 1986 J.A. Balderas-Lopez, A. Mandelis, Self-normalized photothermal techniquefor accurate thermal diffusivity measurement in thin metal films, Rev. Sci. Instrum., 74 (1),

16 Two-beam method - examples () Investigated Materials: metals (Cu, Al, steel), semiconductors (Si, Ge, GaAs, InP), glass, superconductor (YBCuO), plastic (tape), paint layer Detection method: PA, IR radiometry Temperature range: K 16

17 Two-beam method - properties Ratio of front and back independent on detection equipment CW measurement Reference sample not needed Only 1 parameter for fitting Simple mathematical description s 17

18 Conclusions Thermal wave methods are widely used for determination of thermal diffusivity Methods are based on phase-sensitive measurement CW methods do not need expensive pulsed light source Elaboration of standard is important for cooperation with industry 18

19 Acknowledgment This work is supported as part of project Elaboration of System for Measurement of Thermal Diffusivity by Thermal Wave Methods Multi-Year Programme PW-004 Development of innovativeness systems of manufacturing and maintenance , established by a resolution of the Council of Ministers of the Republic of Poland 19