Measurement Principle — Indenter Crush Method

The AHT1000 measures individual particle hardness (crush strength) using the indenter crush method in accordance with JIS K 6219. A flat indenter is pressed down at a constant speed onto particles placed one at a time on a stage, and the load at the moment of particle crush (fracture) is recorded.

Individual particle hardness (MPa) is calculated from the crush load and particle diameter. Statistical analysis including Weibull distribution can also be performed. This enables quantitative evaluation not only of average hardness but also of the variability and failure modes within a particle population.

Automatic Feeding with Proprietary Loader

Conventional individual particle hardness testing required manually placing particles one by one on the stage using tweezers or a micro-manipulator — a time-consuming and labor-intensive process.

The AHT1000 features a proprietary loader mechanism that automatically feeds, positions, measures, and ejects particles one at a time simply by loading them into a hopper. This dramatically reduces the time required to measure 100 particles compared to manual methods, significantly reducing operator workload.

The loader supports particle diameters from 200 to 1500 μm and automatically handles a wide range of samples from carbon black granules to catalyst pellets and ceramic granules. Stable feeding is possible even for non-spherical particles.

Compatible Samples and Applications

The AHT1000 is used for quality control and R&D across a wide variety of particles and pellets.

• Carbon black granules — Evaluating the granulation quality of carbon black pellets used as reinforcing agents in rubber and tires. Used for predicting breakage during transport and optimizing granulation conditions.
• Catalyst carriers — Managing the crush strength of alumina and silica-based catalyst carrier pellets. Assessing fracture risk inside reactors.
• Ceramic granules — Analyzing the strength distribution of spray-dried granules for press forming. Identifying causes of molding defects and improving granulation conditions.
• Pharmaceutical granules and pellets — Evaluating the disintegration and hardness of pharmaceutical granules. Predicting crush behavior during tableting and supporting formulation design.

Image Capture of the Crushing Process

The AHT1000 has a built-in camera that automatically saves sequential images of the process from the moment the indenter contacts the particle until crushing occurs. Reviewing the images after measurement allows visual identification of the failure mode — whether brittle fracture, ductile deformation, or layer delamination.

By cross-referencing load-displacement curves with images, it becomes easier to identify the cause of outlier values and compare fracture behavior between samples. This provides valuable insight for particle design and granulation process improvement.

Comparison with Manual Measurement

Conventional manual particle hardness testing had the following challenges. The AHT1000 addresses all of them.

Key Features

• Supports particles from 200 to 1500 μm
• Proprietary loader for automatic feeding
• Built-in image capture of the crushing process
• Compliant with both JIS and ASTM standards
• High-speed measurement (significantly faster than manual methods)
• PC-connected data management

Specifications