The HSD SLIM Mapper adds 3D-SLIM (Spacer Layer Imaging Method) functionality to the instrument. It uses optical interferometry to measure the thickness of sub-micron films formed between contacting surfaces during a test.
The HSD SLIM Mapper adds 3D-SLIM (Spacer Layer Imaging Method) functionality to the instrument. It uses optical interferometry to measure the thickness of sub-micron films formed between contacting surfaces during a test.
When a mapper step is run, the discs are stopped, and the right disc is pressed against a glass disc with a semi-reflective chromium coating and silica spacer layer. White light is directed through the objective lens and glass disc onto the contact. Light reflected by the chromium coating combines with that from the steel disc surface (through any film present) and an interferometric image of the contact is produced. This is captured by a high-resolution RGB camera. These images can be analysed using the included SLIM analysis software to generate a film thickness map of the contact area.
This method allows observation of film formation and breakdown during a test, and when used together with friction data, it provides insight into the physical and chemical behaviour of lubricants or additives in the contact.
