Diamond-Like Nanocomposites (DLN) as a Protective, Wear Resistant Thin Film for'Sliding Electrical Contacts.

A novel coating technology is proposed for increased wear and improved li fe and reliability of commutator bars in electrical sliding devices found in manned and unmanned underwater vehlilles. Diamond-Like Nanocomposite (DLN) coatings represent a famil Of thiWrfilms that bxhibit unique combinations of technologically interesting properties including high adhesion to virtually any substrate (including metals, crystalline and glass dielettrics, plastics), excellent chemical and diffusion, barrier properti ez4;,good hardnew-rhigh elasticity and flexibility high wear resistance, very high thermal-shock resistance, extremely low friction coefficient, controllable electric properties, and good thermal stability. Substrate size is limited only by chamber size currently a substrate of maxim= size 800 mm can be coated), and both interior and exterior surfaces can be coated. Also, the few-micron thick films can be continuously graded in composition and hence properties tailored from the interface to the bulk. Phase I work will be devoted to a demonstration oflftbbscoatings and performance on acutal commutator bars in DC motors. Motor performance till be compared before and after coating, using several tests intluding efficiency, maximum power, horse power, te n4perature risee and torque. Property measurements will include hardness, electrical conductivity and wear resistance Phase II work w(buld involve improved coating designs and implementation of hardware modifications.