Application notes


For any application questions feel free to contact us (contact), or maybe you can find an answer in one of these demonstrations:

  • Analysis of cement in ethanol suspension (Apn16-SD001)
  • Milled polyethylene characterisation (Apn16-SD002)
  • Sieve correlation (Apn16-SD003)
  • Quality control of atomized powders (Apn16-SD004)
  • Abrasive property of industrial diamond (Apn16-SD005)
  • Dispersion and analysis of a dry aggregated fibers (Apn16-SD006)
  • Analysis of tobacco (Apn16-SD007)
  • 3D pellet characterisation (Apn16-SD008)
  • Characterisation of CMP slurry, high concentration suspention (Apn-16SD009)

Our knowledge goes far beyond this short list so do not hesitate to ask more!

 

 

 

 

 

Apn16-SD001 - Analysis of Hydraulic cement sample in isopropyl alcohol suspension

The standard method for measuring cement is light scattering. The measurement is taken from an isopropyl alcohol solution. Wet dispersion is preferable to dry methods due to the difficulty of storing cement samples while avoiding aggregation issues. Cement particle sizes range from 0.4µm to 1mm; in this paper, we will be proposing a solution to replace laser diffraction (LD) with an image analysis method (IA).

Both methods, LS and IA, use the same isopropyl alcohol suspension so that the analyses are conducted under similar conditions. The instrument used for this application will be the OCCHIO FC200M-HR, with a resolution setting of 200nm/pixel.

The sample analyzed is ASTM C150 CEM 1, general purpose Portland cement.

Advantages of image analysis:

Image analysis is a direct measurement; therefore, you do not need to know the nature of the sample. This is not the case for laser diffraction where it is important to know the complex refractive index; after which, this value must be adjusted if the sample composition changes (e.g. the presence of limestone or other additives).
Ability to visualize the shape of each particle to perform a more accurate and complete sample sizing. The only size available when using the LD measurement method is the equivalent diameter; however, with IA we can compute length, width, inner diameter (sieve diameter), and particle size distribution
Sample dilution is less important when using the IA method as opposed to the LD method. This means we can perform measurements with greater accuracy while using less solvent.
Complete transparency of the entire procedure allowing the user to optimize cleaning of the cell and reduce analysis time.

Apn16-SD002 – High density polyethylene powder characterisation

 

HDPE is used in various industrial applications from simple plastic bottles to more complexly structured materials. Characterization, size, shape, and distribution are key parts of quality control and determine powder behavior.  The OCCHIO 500nano can help you gain a better understanding of your product during production or for final user application reports.

For these measurements we set a resolution of 800nm, dispersion is done directly by using the vacuum dispersing device integrated inside the instrument.

Mean particle size for this sample is 25µm. D10, D50, D90 are respectively 9, 22, 45 µm.

For coating applications is important to understand sample flowability; this property is directly related to the morphology of each individual particle. The bluntness parameter is an excellent estimator of this property.

Apn16-SD002

Apn16-SD003 – Image analysis and sieve size distribution

The weighting of fractions retained in a series of sieves is a reference method that has been used for decades and is duly normalized. Image analysis techniques, only when properly implemented, predict the result of sieving with perfect correlation.

A 6-gram sand sample distributed by the European Bureau for Certified Reference Material, under reference BCR 68, has been analyzed with the Occhio Zephyr ESR. Relative weight fractions have been computed and results are compared to mean and standard deviation data obtained from sieving by five European reference labs. Zephyr ESR achieves perfect results with only a fraction of the material and within a fraction of the time required...to clean the sieves!

 

Advantages of optical over mechanical sieving:

 

• Accurate and real time analysis of individual particles

• Capability of measuring very limited material quantities

• Capability of working with very lightweight and friable material

• Automatically generated report of results

• Normalized or user-defined mesh intervals

• No clogging, no wear

• Simultaneous size and shape analysis

Apn-16SD004 – Quality control of atomized powder, controlling sphericity and detecting satellites

 

Atomization is a major process in the production of powders both in metallurgy and ceramics. It is important to reduce the number of irregular particles so to maintain the ability of the atomized powders to properly fill in a mold or to circulate in an air flow. A common problem is the presence of satellites, nodules on the particle. To ensure the production of spherical and well calibrated particles, a very sensitive and highly accurate quality control process must be implemented. Thanks to a specific shape descriptor exclusive to Occhio technology, satellite detection is fast, simple, and accurate. The Occhio 500nano proves to be a unique instrument to disperse and image such powders. Combined with the exclusive shape analysis capabilities of the CALLISTO software, it becomes a very sensitive tool for identifying deviations in the atomization process.

 

A scatterplot of elongation versus sieving diameters gives a very comprehensive insight into the production. From such data, the number of particles exceeding a critical elongation factor or a given size is precisely monitored. Each output can be compared to a reference sample. The subtle morphometric measurements computed by CALLISTO (roundness (rnd) and elongation (el)) provide unrivalled precision for accurate detection and categorization of satellite particles.

Apn-16SD005 – Quality control of superabrasives

 

Super abrasives are strictly calibrated powders of which performances are critically linked to shape properties. Image analysis is a unique tool to monitor the mechanical separation of particles with different shapes. A systematic imaging of abrasive diamonds, separated into individual batches on a vibrating table, is easily achieved using the 500nanoXY granule morphometry. Further image analysis with our patented CALLISTO software allows accurate monitoring of the size and elongation statistics of individual grains within each section of the table. In addition, an exclusive shape processing algorithm is available to suit the abrasive industry’s needs and quantify angularity and abrasion power of particles!

 

Subtle evolutions from angular to more rounded particles are clearly shown for standard industrial diamond from a process control chart, based on abrasion index measurements, while no significant difference in size exists.

Apn-16SD006 – Dispersion and analysis of fibers sample

 

Fiber sample analyses demand an extremely flexible analyzer. The Occhio 500nanoXY has been developed to cover best the resolution range requested for fiber analysis.

The important ratio between fiber length and fiber thickness (one thousand or even more) must be compensated for by using a high-resolution camera. Here is our choice in settings for the optimization of fiber analysis:

Sample dispersing: we use our vacuum technology to disperse aggregate samples without damaging them
We increase the dispersion surface from 96mm to 140mm diameter (main difference between the 500nano and 500nanoXY)
We incorporate a higher resolution camera
We cover the entire dispersion surface

The adjacent analyses show fiber thickness and length distributions.

Apn-16SD007 – Analysis of tobacco samples

 

Tobacco leaves are cut into smaller strands for cigarette filler and the length of these strands can vary depending on the manufacturer’s production. Due to the difficulty of dispersing this kind of sample, light weight and agglomerating, the Zephyr ESR 2 is fitted with a special funnel to eliminate sample clogging and assure constant feeding from the primary vibrating dispersion to imaging area. It does this by using the vibrator integrated into the dispersion system in coordination with a sonar-like captor. The results are impressive. The funnel can support up to 200gr of tobacco and assure optimal feeding during the entire autonomic analysis.

The goal is to make the entire run without any operator support and guarantee reliable analysis.

Results show two different sample grades, short and long tobacco fibers. The final blend size distribution is an important point in final cigarette quality.

 

 

 

 

 

Apn-16SD008 – three-dimensional pellet characterisation

 

A precise size, shape, and color analysis can be obtained with our newest Morpho 3D particle analyzer. Thanks to the stereoscopic image the size measurement can be computed on the three dimensions of the particle: width, length, and thickness.

The 3D image is not based on estimated values; but instead, the real size computed by the images taken with the dual camera setup. This very precise measurement combined with the powerful Callisto 3D software allows us to reach unrivalled quality control in a very short time.

Following figures depict Polyethylene pellets characterization, width, length, thickness and color analysis.

Apn-16SD009 - Characterisation of CMP slurry, particle counting in high concentration suspension

CMP (chemical-mechanical planarization) process uses colloid slurry to polish semiconductor wafers surfaces. The presence of impurities or over-sized particles must be quantified constantly during slurry production. Ipac 2 CMP offers a complete method to improve particles counting for slurry suspensions.

 

The IPAC 2 CMP platform is based on high-end imaging devices and the newest generation microchip cell.

 

Where we put our efforts:

Increasing the detection of the finest particles by using a dedicated optical bench with a resolution of 172nm/pixel.
Reduce sample dilution, by using 50µ cell thickness we can reduce, or even eliminate, sample dilution (typically 1:1; 1:10; 1:100). The lowest sample dilution improves measurement reliability and sample stability.
High stability lighting and imaging device, we eliminated the derive of the acquisition device (compared with standards light obscuration devices)
Dynamic background function, this intelligent software compares each image with the previous one and allows recognition of only moving particles. This means that dirt on the cell will be filtered out and not counted as a particles giving us the most accurate counting results.
Direct measurement method.

 

 

Device and sample information and method

Instrument:                            IPAC 2 CMP

Calibration:                          172 nm/pixel

Camera sensor size:           12 Megapixels

Cell thickness:                      50 µm

Sample dilution:                   1:1 (undiluted)

Sample type:                         Colloidal silica slurry

Pump type:                            Precision syringe

Particles identification

During the measurement the camera acquires and processes the images in real time, up to 18 images processed per second. All the particles, visible on the image, are identified and stored in the corresponding size classes. Counting distribution is refreshed continuously until the end of the analysis. The adjacent table shows four particles in different size ranges.