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1、Leading Thermal AnalysisAnalyzing determination of the optimum model using statistical criteria Determination of specific heat by means of a comparative method Calculation of thermal conductivityEvaluation Taskn Presentation of an individual response curve, the entire result as well as test paramete
2、rs and measured values in one presentation n Free input or import of density and specific heat values for determination of thermal conductivity n Simultaneous presentation of thermal diffusivity and conductivity data in one plot n Storage and restoration at any point of the analysis n Presentation a
3、nd new evaluation of data from previous measurementsSoftware Featuresn Multitasking: simultaneousmeasurement and evaluation n Full network compatibility n Easy printout and export of measuring curves and data (ASCII) n Selectable screen design bymeans of docking windows n Multi-moduling: operation o
4、fseveral different instruments with one computer n Integrated data baseMeasuring Taskn Full control of the sample changer n Easy and user-friendly input of test parameters n Free selection of temperature programs (heating, coding) n Automatic optimization of the system parameters (measuring time, am
5、plification, etc.) n Automatic evaluation of the measurement after each shot with selected evaluation model6 6Performance - Stainless Steel and Pyroceram 9606The thermal diffusivities of two well- known standard materials (NIST SRM 1461 Stainless Steel and Pyroceram 9606) were measured versus temper
6、ature with the LFA 447 NanoFlash: The figure shows the measurement results as compared to literature values (Touloukian et al., 1970, Henderson et al., 1998) up to 200 C. It can clearly be seen that the deviations between the literature values and the measurement results are less than 3 % (error bar
7、s). This demonstrates the high accuracy of this flash unit in the field of metals and ceramics.Accuracy - NIST SRM 8421 Electrolytic IronA certified NIST thermal conductivity reference material (SRM 8421) was measured between room temperature and 100C. Additionally shown are the NIST values for the
8、thermal conductivity for this material together with the stated accuracy (3 %). As expected, both the thermal diffusivity and thermal conductivity decrease with temperature. It can be seen that the determined thermal conductivity values are close to the NIST values. The measured deviations are withi
9、n the stated uncertainty range for this certified standard reference material.LFA 447 NanoFlash for a Wide Variety of Applications 7Thermal Conductivity Determination Polymer TapeThe LFA 447 NanoFlash allows easy and fast temperature-dependent measurement of the thermal diffusivity. Additionally, th
10、e specific heat can be determined by employing a comparative method. A direct determination of the thermal conductivity is possible, if the bulk density of the material is known. This method was used for the thermo- physical properties charaterization of a polymer tape between room temperature and 9
11、0C. The calibration standard for the specific heat determination was Pyroceram 9606. It can clearly be seen that both the thermal diffusivity and specific heat changed significantly versus temperature. The resulting thermal conductivity depicts nearly no temperature dependence.In-Plane Tests Fiber-R
12、einforced EpoxyMore and more polymers, metals or ceramics are being reinforced with fibers to improve their bending strength and to adjust them to special applications. In many cases, the fiber reinforcement results in a high degree of anisotropy to the mechanical and thermal transport properties. B
13、y employing special sample holders, the flash technique allows analysis of this anisotropy in the thermal diffusivity and thermal conductivity. The measurement example clearly demonstrates that the values for both the thermal diffusivity and thermal conductivity, perpendicular to the fiber direction
14、 are significantly lower than the results of the in-plane test (in the fiber direction).8LFA 447 NanoFlash for a Wide Variety of ApplicationsMTX-ResultsThe result shows the influence of a thermal conductivity paste between two aluminum plates. In the areas of poor contact or missing paste, values we
15、re obtained in the apparent thermal diffusivity, which were very low. The areas of good contact appear as high values in the apparent thermal diffusivity. Such an analysis can be carried out without disassembling of the composite system.9up to 25.4 mm (1“) diameter, or 8 mm / 10 mm / 12.7 mm square,
16、 up to 3 mm (0.12“) thick, specials on requestScanning range: 50 mm x 50 mm, resolution: down to 0.1 mmAmbient, or as controlled by external fluid source Ambient to 300C (also below room temperature as controlled by external fluid source) Test temperature: ambient (up to 300 C with standard sample carrier)0.01 mm2/s to 1000 mm2/s0.1 W/(mK) to 2000 W/(mK)Thermal Diffusivity: +/-2 % Specifi
