NEW CLASS OF LUBRICANTS FOR GREEN TRIBOLOGY

The possibility of obtaining a new class of lubricating oil bodies (PET-acylglycerol) with the help of modification of the natural fat molecule by a fragment of a link of a synthetic polymer-polyethylene terephthalate is considered. The distribution of electrostatic charge in molecules of beef fat and synthesized PET-acylglycerol is shown. A relationship between the structural hierarchy of the synthesized lubricating oil bodies and the tribotechnical indexes has been established.

FROM HEAVY DUTY LUBRICANTS TO BIOBASED FLUIDS – LEGACY OF JOSEPH PEREZ

Advancement in lubricant technology is driven by technical demands, oil market, innovations from related chemical areas and other conventional factors. Nevertheless, a personal impact of an individual scientist can also be very important. Few individuals can claim to have accelerated lubricant progress more than Dr. Joseph M. Perez, who initiated many new developments in lubricant technology and drove them to large scale implementation. Early in his career at PennState he worked on aerospace lubricants, developing highly efficient additives for supersonic planes. When working at Caterpillar he dealt with hydraulic fluids, gear oils and many heavy duty lubricants. During employment at NIST and upon return to PennState Dr. Perez realized the importance of vegetable oils. He pioneered many research directions for their applications, becoming directly involved in vegetable-based engine oils, hydraulic fluids, greases, biodiesel, elevator fluids and many other areas. His innovative thinking, enthusiasm and initiatives will be sorely missed by lubricant researchers.

SELECTED ASPECTS OF WEAR AND SURFACE PROPERTIES OF POLYPROPYLENE BASED WOOD-POLYMER COMPOSITES

The work demonstrates selected results of the investigations on surface properties and wear resistance of polypropylene based wood-polymer composites (WPC) reinforced with wood flour. WPC are broadly applied in construction and automotive sectors, where mechanical, thermal as well as moisture absorbing characteristics are of great importance. In order to get information about wear resistance of such composites Taber wear test is applied. Surface properties are investigated before and after tribological test. Contact angle values of the investigated compositions are compared after different wear periods (0, 2000, 5000 and 10000 cycles) with abrasives H22 and CS17.

WEAR RESISTANCE OF ELECTRODEPOSITED Fe-W ALLOY COATINGS UNDER DRY CONDITIONS AND IN THE PRESENCE OF RAPESEED OIL

Amorphous Fe-W alloys with 25 at.% of W were electrodeposited under direct and pulse modes from glycolate-citrate bath with and without addition of polyethylene glycol. The tribological behavior of the coatings was studied at 1, 2 and 5 N loads under dry friction and in the presence of rapeseed oil films of 0.2-5.0 m thickness. The tribological behavior of obtained coatings at dry friction reveals their severe tribo-oxidation resulting in a high wear depth and coefficient of friction. Observed groove like surface with well-adhered particles inside the wear track point out on abrasive-adhesive wear mechanism of Fe-W alloys. In the presence of rapeseed oil films the wear mechanism changes, and values of coefficient of friction decrease up to 10 times compared to dry friction conditions. The optimum thickness of rapeseed oil film was 1 μm. This film has the satisfactory adhesion and uniform distribution on the surface, and could withstand up to 2 000 cycles.