Metrology CT : Non-destructive 3D inspection of internal/external geometry

Metrology CT is the fusion of metrology and X-ray Computed Tomography (CT). X-ray has long been used for industrial applications. With X-ray CT a number of 2D X-ray images are taken at different angles around the sample. All of the external and internal geometry is captured as the X-rays pass through the sample. CT software constructs a 3D model of the sample using these 2D images. Dimensional characteristics such as size, position and form can be measured directly using the model as well as full part-to-CAD comparison, section reporting and GD&T analysis.

Absolute accuracy of 9μm + L/50 and 2μm feature detectability

The MCT225 offers absolute accuracy of 9μm + L/50, and 2μm feature detectability. Absolute Accuracy guarantees measurement accuracy without time consuming comparative scans or reference measurements. Samples are simply placed on a rotary table inside the enclosure and measured. The CT system is pre-calibrated using accuracy standards traceable to the UK’s national measurement institute (NPL) and verified using VDI/VDE 2630 guidelines for Computed Tomography in Dimensional Measurement.

A key component of the MCT225 system is the in-house developed Nikon Metrology 225 kV micro-focus X-ray source. It produces incredibly sharp images with low noise levels, enabling magnification levels up to 150x with 2 µm feature detection.

MCT225 is pre-calibrated using accuracy standards traceable to the UK's national measurement institute (NPL) and verified using VDI/VDE 2630 guidelines for Computed Tomography in Dimensional Measurement. “Absolute accuracy” guarantees measurement accuracy without time consuming comparative scans or reference measurements; samples are simply placed on a rotary table inside the enclosure and measured.

High-precision mechatronics increase sample manipulation accuracy

The MCT225 is equipped with a fully programmable 5-axis precision and large capacity sample manipulator. The manipulator has been optimized through Finite Element Analysis (FEA). The design of the manipulator benefited from 50 years of CMM development expertise, to ensure highly accurate sample movement.

High precision linear guideways and axis travel error correction offer accurate and repeatable motion within the temperature controlled enclosure. High resolution optical encoders also fit this strategy for maximum precision. X-ray images taken by a high resolution 4-Megapixel detector is the starting point for the system’s high performance digital imaging and processing.

• Large capacity manipulator for samples up to 5 kg that fit in a measuring volume of 250 mm diameter and 450 mm height
• Long manipulator travel: 480 mm (18.89”) in x direction, 450 mm (17.71”) in y direction, 730 mm (28.74”) in z direction, and rotation in 360 degrees

Straightforward manual use and automated process flow

The unique CT Wizard guides the operator every step of the way from sample loading to creating the final inspection report. Settings are automatically optimized for accuracy and image quality without compromising on productivity. Accelerated reconstruction of the sample volume, using optimized graphics cards, reduces the total process time from hours to minutes. 
Macros allow for automated workflows that execute repeated CT data capture. After recording a macro, an operator positions a sample on the manipulator table and starts the procedure. The MCT225 system automatically moves the sample while X-ray images are being taken. When the imaging cycle is completed, the operator can switch specimens and re-start the procedure.

Powerful visualization and analysis provide detailed insight

The unique CT Wizard guides the operator every step of the way from sample loading to creating the final inspection report. Settings are automatically optimized for accuracy and image quality without compromising on productivity. Accelerated reconstruction of the sample volume, using optimized graphics cards, reduces the total process time from hours to minutes.

Reporting and analysis features include:

• Part-to-CAD comparison with color mapping
  Surface measurement using surface and voxel data
  Geometric feature inspection
  Geometric Dimensioning and Tolerancing (GD&T)
  3D visualization of the sample volume

The same dataset can easily be used for measurement and defect analysis (NDT).

Flexible efficiency for a wide variety of applications

MCT255 is an invaluable asset for manufacturers seeking to benefit from reduced leads times and inspection cycles. The powerful X-ray source and large capacity manipulator combine with high magnification and small feature detection to create a solution suited to a wide variety of applications.

Plastic injection-mold and metal die-cast manufacturers can significantly reduce correction cycles during tool development and production start-up, accelerating time to market for new products. All shrinkage, deformation and dimensional errors are clearly identified in easy to understand inspection reports making it easier to define corrective actions.

Emerging production techniques like additive manufacturing now make it possible to produce small and highly complex components that can’t be inspected using touch probes or optical sensors. Here too MCT225 makes it possible to measure and analyze these components in a single non-destructive operation.
The high-precision microfocus 225 kV and 225 kW source penetrates different materials. The thickness of the samples the can be fully penetrated by the X-ray beams depends on the material density.

• Material penetration: plastic 170 mm (6.7”), aluminum 75 mm (2.9”) and iron 15 mm (0.6”). Other suitable materials include: steel, ceramic, carbon fibre and wood.
• Large capacity manipulator for samples up to 5 kg that fit in a measuring volume of 250 mm diameter and 450 mm height

Open tube technology reduces Cost of  Ownership

The open-tube technology of the new source fitted in the MCT225 reduces the cost of ownership. The serviceable open-tube source allows for quick and straightforward replacement of the filament, saving time and money.

¹Applies only to single material samples with a maximum diameter of 250 mm (9.84") and maximum height of 250 mm (9.84")