Friability Tester
Toughness Index (TI) Determination
The Friability Tester measures the impact strength value (Toughness Index – TI) of diamonds. This method is often used to obtain a general assessment of a diamond sample’s quality.
More than just one value.
The Toughness Index represents a diamond characteristic that cannot be directly measured through physical parameters. Instead, it must be assessed in relation to the average combinations of hardness and resiliency of a limited number of diamond grains considered a representative sample of the material being analyzed.
Two Versions.
ST 1 & ST 4.
There are two versions of the Friability Tester. The ST1 is designed specifically for testing industrial diamond. The ST4 allows for the selection of four different mechanical loads.
Both versions of the Friability Tester feature a specialized mechanism to apply the necessary forces to the samples using steel balls. The number of cycles can be preset for precise control.
Shake it Baby.
Operating Principle.
A well-sieved 2 cts. diamond sample is shaken in a specialized capsule with a steel ball. The number of cycles varies based on the grain size. The process may partially crush the diamonds. The Toughness Index (TI) is calculated as the percentage of undamaged grains.
Additionally, the Friability Index (FI) can be determined based on the number of cycles needed to crush 50% of the grains.
Taking it a Step Further.
Thermal Toughness Index (TTI).
For measuring the Thermal Toughness Index (TTI), we recommend using our DiaHeat v4 device, a specialized furnace engineered for heating diamond in a protective gas environment.
Technical Data
| Version ST 1 | For Diamonds for working stones |
| Version ST 4 |
For
|
| Measurement |
500 … 7,000 (shaking cycles) |
| Measurement range |
Grain size: 325/400 … 18/20 US-Mesh |
| Duty cycle |
20 % max. working duty cycle |
| Shaking frequencies |
ST 1: 1, ST 4: 4 |
| Power supply |
230 V A.C. (50 Hz) or 110 V A.C. |
| Power input |
max. 420 W |
| Protection class |
IP 54 |
| Dimensions |
465 x 225 x 195 mm |
| Weight |
ca. 35 kg |
|
Recommended accessories (not included, available separately)
|
Measurement capsules, Steel balls, Sieves (electroformed), Analytical sieve shaker, Electronic scales |