DLF 1600

High Power Laser and Advanced Optics 

The DLF 1600 features the industry’s most powerful and robust laser light source and most efficient delivery system. The proprietary Class 1 Neodymium-Phosphate Glass laser and fiber optic power wand system, with built-in alignment, ensures effective generation and delivery of laser energy to the sample.

• Proprietary laser designed and manufactured by TA
• 40% more energy delivered to the sample surface than the closest competitive system
• 99% homogenized laser energy profile
• Noise-free design – The separation of the laser and furnace modules eliminates the effect of electromagnetic interference, and ensures long-term optical alignment stability.

Flexible High Productivity Sample Carousel

Only the DLF 1600 comes standard with a carousel enabling simultaneous testing of up to five samples in a single experiment to 1600°C. The carousel accepts samples up to 15.9 mm diameter and 10 mm thick, 20% larger and 50% thicker than any competitive high-temperature light flash instrument. Optional trays and adapters can accommodate a variety of sample dimensions and shapes, including round and square. Specialty sample holders are available for liquids, powders, pastes, laminates, and in-plane testing of thin films.

1600°C Furnace

The clever design of the DLF 1600 furnace sets it apart from competitive light flash analysis instruments in every aspect of temperature performance. The furnace employs high quality molybdenum silicide (MoSi₂) heaters, a high-purity alumina muffle tube, and multiple baffles along its length preventing thermal disturbances. The result is a furnace designed to provide the most stable and uniform heating for reliable control of the sample at 1600°C. When operating the DLF 1600, every sample in the carousel absolutely reaches and maintains the programmed temperature from ambient up to 1600°C throughout the testing time. Sample testing can be conducted in static or dynamic atmospheres, including vacuum, oxidizing, or inert gas purge. The result is the most reproducible thermal diffusivity measurements available from RT to 1600°C.

Precision IR Detector and Optics

The DLF 1600 includes a high sensitivity liquid nitrogen cooled Indium Antimonide (InSb) IR detector with an optimum signal-to-noise ratio over the entire temperature range. A built-in liquid nitrogen dewar delivers unattended 24-hour operation for extended experiments free from interruptions. Additionally, the optics in the detector path ensure uniform and accurate measurement of the sample thermogram. The IR detection area covers more than 90% of the sample surface, therefore representative data is collected without contributions from extraneous radiation, including edge effects such as “flash through” caused by imperfect sample preparation.

Unmatched Accuracy and Repeatability

Accuracy, which defines how close a set of measured data are to the true value, is paramount in understanding how well an instrument performs under known conditions. The figure to the top right shows results of three consecutive experiments on a Molybdenum sample compared to the reference value. The data show the DLF 1600 accuracy is better than ±2%, well within the 2.3% specification, across the entire temperature range. It is important to note that, even at the maximum temperature of 1600°C, the results are outstanding with a deviation of only 1.26%.

The repeatability, or precision, of a measurement system is determined by the variation of multiple measurements on the same instrument under the same conditions. The bottom figure to the right shows measurement repeatability on five molybdenum samples tested from room temperarure to 1600°C at intervals of 100°C. The deviation from the average is less than ±1% with almost 80% of the results within ±0.5% of the average. These results are well within the specification of ±2%, across the entire temperature range demonstrating the unmatched repeatability of the DLF 1600.

The Most Accurate Diffusivity Measurements – Even Under the Most Extreme Conditions

The ability of any instrument to make an accurate measurement relies on all design elements working together efficiently as a system. On a light flash instrument, these components include the light source, the pulse delivery, the detector, and the furnace. A good way to understand the performance of a light flash system is to evaluate a sample under conditions that push measurement limits of all components simultaneously. Such an extreme case for light flash is a sample at the maximum thickness and the maximum temperature.

A 9.9 mm thick thermographite sample, 65% thicker than the maximum allowed on competitive instrumentation, was tested on the DLF 1600 from 100 to 1600°C at intervals of 100°C. The raw data thermogram is shown for the most difficult measurement at 1600°C in the top right figure. It can be seen here that the DLF 1600, with its combination of high energy proprietary laser and pulse delivery, high temperature furnace with uniform heat zone, sensitive IR detector, and 16-bit data processing yields high signal-to-noise ratios for excellent thermogram results under the most demanding conditions.

The graph to the lower right shows the results of the thermal diffusivity of the 9.9 mm thick thermographite sample compared to two thinner samples, 3.2 mm and 6.1 mm thick, superimposed with reference data. The results in the figure clearly show the superior design of the DLF 1600 to make accurate measurements over the widest range of conditions. All values reported fall well within ±2% of the reference. Even under the most extreme conditions, at maximum thickness, over 50% of the thermal diffusivity measurements show a deviation of less than 1%.