LFA 500

Simple and cost-effective measurement of thermal conductivity

Description

To the point

Information about the thermophysical properties of materials and the optimization of heat flows in end products is becoming increasingly important in many industrial applications. In recent decades, the flash method has become the most widely used technique for determining the thermal diffusivity and thermal conductivity of solids, powders and liquids.

The LINSEIS Light Flash LFA 500 series is ideal for determining/measuring the thermal diffusivity, thermal conductivity and specific heat of up to 18 samples in a temperature range from -100 °C to +1500 °C.

Measuring principle:

The sample to be measured is positioned horizontally on the sample carrier / sample changer in an IR or resistance-heated furnace. The furnace heats the sample to a fixed isothermal temperature. The underside of the sample is then irradiated by a programmed energy pulse using a laser or xenon flashlamp.

This energy pulse leads to a homogeneous temperature rise on the top of the sample, which is measured against time using an infrared detector. The temperature and thermal conductivity can be calculated from this measurement data.

High temperature configuration

The Light Flash Series LFA 500 is available with different furnace options (-100 up to 500°C, RT up to 500/1000°C or 1250°C, 1500°C with boost), ensuring the right temperature range for your application.

Sample Robot

Each Linseis LFA 500 model is equipped with a sample robot for maximum sample throughput. LFA 500 – 500/1000 with up to 18 samples, LFA 500/1250 with up to 5 samples.

COMBINED “DUSZA” MODEL

Worlds only combined solution for combined heat loss and finite pulse corrections for the flash method.
One fits all model. No more uncertainty of selecting the appropriate model.

DUSZA – Combined model for Translucent Samples

Accounts for the distinctive problems relating to translucent samples and ensures perfect measurement results.

High Speed IR or Micro-heater furnace

Fast measurements cycling due to very fast heating and cooling rates.
Perfect temperature control with low mass furnace, no measurement error due to temperature fluctuation at sample.

 

Unique Features

Wide temperature range:
-125°C to 2800°C

High measuring accuracy
and repeatability

Modular design for
flexible customization

Fastest measuring times thanks
to laser/light flash technology

User-friendly software for
comprehensive data
analysis

Suitable for solids,
layers and liquids

Service-Hotline

+01 (609) 223 2070

 

+49 (0) 9287/880 0

Our service is available Monday to
Thursday from 8-16 o’clock
and Friday from 8-12 o’clock.

We are here for you!

Specifications

Black on white

MODEL

LFA 500

Temperature range*:-50 to 500°C, -100 to 500 °C, RT up to 500°C / 1000°C / 1250°C (1500°C with boost)
Heating rate:0.01 up to 300°C/min
Pulse source:Flash lamp, user replaceable
Pulse energy:up to 15J/pulse (variable pulse energy: software-controlled)
Energy adjustable:Yes
Measuring range alpha:0.01 to 2000 mm2/s
Measuring range lambda:0.1 to 4000 W/(m∙K)
Reproducibility cp:±3% (for most materials)
Reproducibility alpha:±1.9% (for most materials)
Accuracy cp:±5% (for most materials)
Accuracy alpha:±2.4% (for most materials)
Pulse length:Software controlled
Sample size:∅ 3, 6, 10, 12.7 or 25.4 mm
rectangular samples 10×10 or 20×20 mm
Sensor:InSb, LN2 cooled
Sample thickness:0.1 mm ... 6 mm
Number of possible samples:Sample robot for up to 18 samples
Sample holder:metal, SiC, graphite, Al2O3
Variant available for liquids, powders or pastes
Atmosphere:inert, oxidising, reducing, vacuum
Electronics:integrated
Data acquisition:2 MHz
Interface:USB
*Other temperature ranges on request

Software

Making values visible and comparable

All thermo analytical devices of LINSEIS are PC controlled, the individual software modules exclusively run under Microsoft® Windows® operating systems. The complete software consists of 3 modules: temperature control, data acquisition and data evaluation. The Linseis software encounters all essential features for measurement preparation, execution and evaluation, just like with other thermo analytical experiments.

LFA Features

  • Precise pulse length correction, pulse mapping
  • Heat-loss corrections
  • Analysis of 2- or 3-layers systems
  • Wizard for selection of the perfect evaluation model
  • Specific heat determination
  • Contact resistance determination in multi-layer systems
  • Multi-method analysis: DIL, STA, LSR and LZT

Evaluation Software

  • Automatic or manual input of related measurement data (density, specific heat)
  • Model wizard for selection of the appropriate model
  • Finite pulse correction
  • Heat loss correction
  • Multilayer model
  • Determination of contact resistance
  • Cp (Specific Heat) determination by comparative method

Measurement Software

  • Easy and user-friendly data input for temperature segments, gases etc.
  • Controllable sample robot
  • Software automatically displays corrected measurements after the energy pulse
  • Fully automated measurement procedure for multi sample measurements

Applications

Application: PTFE “Polytetrafluoroethylene”

PTFE is a versatile material and used in many different industries/applications such as chemical processing and petrochemical sectors: used for vessel linings, seals, spacers, gaskets, well-drilling parts and washers, since PTFE is chemically inert and resistant to corrosion. Laboratory applications: Tubing, piping, containers and vessels due to resistance to chemicals and the absence of contaminants attaching to the surface of PTFE products. Electrical industry: used as an insulator in the form of spacers, tubing and the like Virgin PTFE had been approved by the FDA for use in the pharmaceutical, beverage, food and cosmetics industries in the form of conveyor components, slides, guide rails, along with other parts used in ovens and other heated systems. Semiconductor sector: used as an insulator in the production of discrete components such as capacitors and in the chip manufacturing process.

Application: BCR 724 glass ceramic

BCR 724, a standard glass ceramic has been measured using LFA 500. Therefore, a small disc of 1 mm thickness and 25 mm diameter was cut out of a plate of bulk material and coated with graphite for the measurement.

The LFA 500 gives the thermal diffusivity as a direct function of temperature. The Cp data was obtained in a comparative way by measuring a known ceramic standard under the same conditions in a second sample position of the same sample holder. Using this, the thermal conductivity was calculated out of the product of density, specific heat and thermal diffusivity. The result shows a slightly decreasing thermal diffusivity and conductivity while the Cp value increases over temperature.

Application:  Graphite reference

A graphite sample has been investigated using the LFA 500. Thermal diffusivity has been determined directly at several temperature between RT and 1100°C. Specific heat capacity has been determined using a known graphite standard in a second sample position as a reference in the same measurement. The product out of diffusivity, specific heat and density gives the corresponding thermal conductivity. The result shows a linear decreasing thermal conductivity which is typical and a thermal diffusivity that is showing a plateau above 500°C. The Cp is slightly increasing over temperature.

Application: Reproducibility investigation

Pyroceram, a glass ceramic trademark of Corning used as a standard material in various applications, has been measured using the LFA 500 to show the reproducibility of thermal diffusivity values. In total 18 measurements were performed with 18 samples that were cut out of one bulk block. Each sample was measured separately and the result shows a spread in the result that is in a range of +/- 1 % in a temperature range up to 600°C.

well informed

Downloads

Everything at a glance