Optical Profilometry Replica Metrology Protocol for Mould Cavity Topography
Indirect optical profilometry on elastomeric cavity replicas yields sub-micron texture data while eliminating tool teardown and optical access limits.
Vinyl Polysiloxane
Meaning
Addition-cure silicone elastomers provide high dimensional stability and detail reproduction for creating replicas of tool surfaces. Vinyl polysiloxane is a two part material that undergoes a chemical reaction to form a flexible solid with negligible shrinkage. It is used in industrial metrology to capture the texture of areas that cannot be reached by a stylus or a camera.
The curing process ends within a few minutes at room temperature.
Material Chemistry
Formulation of the base and the catalyst prevents the formation of byproducts like water or alcohol. This lack of volatiles in vinyl polysiloxane ensures that the replica exactly matches the volume of the original cavity. The resulting polymer is resistant to tearing and can be removed easily from complex geometries.
Replication Accuracy
Sub micron features are preserved in the silicone surface. Impressions made from vinyl polysiloxane allow engineers to measure the roughness of a mould without cutting the tool apart. The replica is then inspected using optical profilometry to generate a digital map of the texture.
Industrial Usage
Monitoring tool wear over time is possible by taking periodic impressions of the mould. Comparing replicas of vinyl polysiloxane reveals the rate of erosion or the buildup of polymer residue. This data helps in scheduling maintenance before the part quality falls below the specified limits.