Keyence 4K Ultra-High Accuracy, 3-Dimensional Microscopy with Integrated LIBS Elemental Analysis
Keyence Capabilities
- 4K CMOS Image Sensor
- Zoom Magnification from 20X to 2000X
- Motorized Lens and Sample Stage
- 3-Dimensional Image Construction from the in-focus areas of many z-displaced images provides high depth of field at high optical resolution
- Unlike SEM Images, Color Information is Retained, Providing Chemical Phase Information
- Large-Area Imaging by Stitching Images Together
- Ring and Co-Axial Lighting, Quadrant Ring Lighting, Quadrant Through-the-Lens Lighting, Mixed Ring and Co-Axial Lighting – A given illumination draws out different features of a surface
- Calibrated 2-Dimensional and 3-Dimensional Distance Measurements
- Particle Size and Grain Size Analyses Using Advanced Image Analysis
- Surface Topography Profiles with Surface Roughness Measurement over Lines and Areas
- Integrated with LIBS (Laser-Induced Breakdown Spectroscopy) for Elemental Analysis of Small Volumes of Material
Small Particle Analysis for Environmental Investigation
An examination of debris collected from an industrial roof to determine the sources of aluminum, zinc, and copper was undertaken to determine if these elements were likely to arise from a commercial enterprise’s manufacturing processes. The location was very near heavy traffic major highways. The 3D image above shows tire wear particles, many silicate particles, and organic fibers. The tire wear particles were distinguished from possible bitumen by heating the debris to a temperature of 250oC. Bitumen will flow into smoothed shapes at this temperature. There was almost no bitumen in the sample, but there were many, many tire wear particles. LIBS elemental analysis of 83 particles and fibers found that almost all the aluminum was in the form of various aluminosilicates. Only two particles had detectable zinc. which was at low concentrations in silicates. Only one particle had a detectable copper concentration, which was also in a low concentration and in the form of a silicate. These silicate particles were all expected as wind blown dust, given that this location was downwind from a mountain range with much bare dirt. XPS analysis found that there was more zinc than that found by LIBS, but it was only on the immediate surfaces. LIBS has an analysis depth at least 250 times deeper than does XPS. Given the tire wear particles and their greatly deteriorated state, indicated by the extensive exposure of fine silica particles used as tire rubber filler and due to long UV exposure, it appeared likely that the zinc residue was due to zinc oxide vulcanization of tire rubbers resulting in nanoparticles of zinc oxide.
Foreign Object Debris in Mixed Salt of High-Value Battery
Several small particles were brought to us for identification after they were found in a mixture of salts for high-value batteries. Among those particles, was the nearly complete insect in the upper image. The texture of its body, seen in the lower high resolution image, and the texture of its wings in similar high resolution images, made the identification of many of the other particles more certain because of common surface textures and coloration. A smaller number of non-insect foreign particles were identified using LIBS.
Surface Roughness Measurements
Linear and surface roughness parameters can be measured for a surface along a line or for a surface area. The 3-dimensionally focused surface can be referenced to a fitted plane for tilt correction or to fitted spheres or cylinders. The measured surface parameters are:
Sa, Arithmetic mean deviation
Sq, Root mean square deviation
Ssk, Skewness
Sku, Kurtosis
Sp, Maximum peak height
Sv, Maximum valley depth
Sz = Sp + Sv
The surface roughness parameters for a polished stainless steel square tube are given below as an example:
