Proceedings of SerbiaTrib '13

chemical vapor deposition method with useorganometallic compounds, studying multilayeredand tribological properties of the obtained coatingsand an estimate of possibility of their application inthe capacity of candidate materials for precisionfriction pairs.2. EQUIPMENT, TECHNIQUES, AND USEDPROCEDURESMaking Mo-С coatings was carried out by athermal decomposition of metal-containingcompound – molybdenum hexacarbonyl Mo (CO) 6 .Process development was carried out using gasphaseunit of Avinit installation intended fordeposition of the multilayered functional coatingsby means of complex methods (plasma-chemicalCVD, vacuum-plasma PVD (vacuum-arc,magnetron), and processes of ion saturation, andtreatment of surfaces by ions) united in onetechnological cycle), presented in [7].Process of coating application was controlled bymeans of temperature of the sample, workingpressure in the chamber, and a method ofevaporation of molybdenum hexacarbonyl.For heating of the sample, high-frequency heaterwas applied with working frequency of 3 MHz andeffective power ~ 0.2 kW. Pressure was controlled bydynamical changing of velocity of a pumping-out ofvacuum system within 2.6 … 13 Pa (0.02 … 0.1 torr).Carbonyl evaporation was carried out under twoprocess flow charts:• The process flow chart of excessiveevaporation when a considerable quantity ofcarbonyl was evaporated within a containervolume. Then, along the heated up steampipeline through the adjustable valve, the gasmixture immediately supplied to the sample.It allowed obtaining major streams ofcarbonyl and, accordingly, highconcentration of molybdenum in a reactionlayer. In this case the carbonyl streamdepended on temperature of the carbonyl.• Under other process flow chart (the residualatmosphere) evaporation of a small amountof carbonyl was made immediately insidechamber volume. Thus, the uniformconcentration of the reaction gas consistingof carbonyl and carbonic oxide vapors wasobtained. At that, molybdenum volumeconcentration in a chamber atmospheredecreased with the course of process.3. PROCEDURES OF EXAMINATIONDuring metallographic analysis the multilayeredand microlayer coatings on the basis of system Mo-C were deposited on samples.Samples were made of structural steelDIN 1.2379 (Х12Ф1) and heat steel DIN 1.7709(25Х2МФ (ЭИ10) which are the materialscommonly used in the industry.Samples made of steel DIN 1.7709 (25Х2МФ(ЭИ10) with a size of 20х10х5 mm were polishedaccording to factory production method up to 8grade surface roughness (R a =0.32 μm).Microhardness was НВ~900.Samples made of steel DIN 1.2379 (Х12Ф1),56... 61HRC, with a size of 10х10х10 mm werepolished to surface roughness of 10 grade(Ra=0.063 μm) to demanded geometricalparameters (nonflatness ≤ 0.001мм, surfaceroughness – Ra 0.08 μm).Tribological tests of antifriction and wearproperties and seizure of samples with coatingswere carried out with friction and wear machine2070 SMT-1 under the "cube" - "roller" test patternat an incremental loading (with increments of200N) in 1-20 MPa loading range according to theprocedures presented in [8, 9]. The linear slipvelocities - 1.3m/s. Time of tests in each cycle –150 seconds. Operating fluid is fuel ТS-1, GOST10227-86.For reproducibility of results of wearing tests,mating of face surfaces by size of the contact areawas controlled: not less than 90 % of a workingarea of each sample.During tribological tests there were registered:– Values of frictional force F tr , normal loadingN, contact pressure P, by which value mechanicallosses in tribosystems were estimated;– Temperature of devices was continuouslyrecorded in real time during the tests in immediateproximity (1 mm) from a friction zone, withapplication of the sliding thermocouple. Frictioncoefficients were determined as f = F tr /N.4. RESULTS4.1 Deposition of coatingsTechnological information for process ofcoating deposition on steel DIN 1.7709 (25Х2МФ(ЭИ10) is presented in Tables 1.1, 1.2 and 2.13 th International Conference on Tribology – Serbiatrib’13 185