Laboratory of Tribology
The laboratory’s infrastructure includes two instruments for studying the mechanical and tribological properties of various types of bulk materials and thin-film coatings: a “Precision multifunctional tribometer for micromechanical studies of friction and wear over a wide temperature range” and a “Calotester for thickness measurement”, which fully meet the requirements of standardised test methods.
Description of Activities
Service Description
- Development of methods for tribometric testing of samples with single-layer and multilayer hard and superhard PVD coatings deposited on various types of materials.
- Testing under various operating conditions – dry static and kinetic friction, abrasive wear, erosion:
- Scratch tests and wear tests (Slow Linear Wear) of single-layer and multilayer coatings at room temperature;
- Dry ball-on-plate and pin-on-plate testing, or testing in lubricant media, of multilayer hard and superhard coatings. Parameters determined: coefficient of friction; wear resistance; wear coefficient.
- In-situ study of the wear resistance of multilayer hard and superhard coatings during heat treatment in the range 25-1000oC.
- Determination of the thickness of single-layer and multilayer PVD coatings deposited on various types of materials.
- Determination of the wear rate of PVD coatings – by combining the Tribotest and Calotest methods.
- Processing and analysis of the experimental results.
- Preparation of test protocols, reports and research summaries.
Equipment
PRECISION MULTIFUNCTIONAL TRIBOMETER UMT TRIBOLAB, BRUKER
The UMT Tribolab tribometer (Bruker) is the only instrument in Bulgaria built on a modular principle for testing under conditions corresponding to real ones over a wide temperature range (up to 1000oC). It is fast and sensitive, with high torque and very precise force measurement (±1µN). The load range is from 1 to 2000 N. The linear module allows precise linear motion and positioning for adhesion, wear and hardness tests. The reciprocating module is designed for dry testing or testing in lubricant media. The rotary module is used to study materials that are subjected to sliding under real conditions. The module allows rotation at speeds from 0.1 rpm to 5000 rpm. The interchangeable temperature chamber for the rotary module enables testing in the temperature range 25-1000oC. The tribometer is connected to a computer equipped with specialised software for system control, data acquisition and data processing.
CALOTESTER CAT2, ANTON PAAR
The CAT2 calotester (Anton Paar) is designed for the rapid determination of the thickness of single-layer and multilayer coatings in the range from 0.1 µm to 50µm by grinding a spherical crater through the coating and into the substrate using a rotating steel ball and an abrasive suspension. The coating thickness is calculated automatically from the diameters of the resulting circles and the diameter of the grinding ball. It consists of three modules: an automated benchtop instrument; an optical microscope with two objectives and a CCD camera; and a computer with specialised software for thickness measurement and recording of the results. The available analysis software handles various types of samples (flat, spherical and cylindrical).
Access to the Laboratory of Tribology
The Laboratory of Tribology is part of the research infrastructure of the National Centre of Excellence “Mechatronics and Clean Technologies” and is located on the Geo Milev campus. Requests for access and for joint research are therefore handled centrally — see Contact. In addition, a full overview of the Centre’s other laboratories is available on the Infrastructure and Laboratories page.
The equipment of the Laboratory of Tribology was established under project BG16RFPR002-1.014-0006, funded by the Research, Innovation and Digitalisation for Smart Transformation Programme 2021–2027 and co-financed by the European Union through the European Regional Development Fund.