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In the present study, friction coefficient and wear rate of stainless steel 304 (SS 304) sliding against mild steel are investigated experimentally. In order to do so, a pin on disc apparatus is designed and fabricated. Experiments are carried out when smooth or rough mild steel pin slides on SS 304 disc. Experiments are conducted at normal load 10, 15 and 20 N, sliding velocity 1, 1.5 and 2 m/s and relative humidity 70%. Variations of friction coefficient with the duration of rubbing at different normal loads and sliding velocities are investigated. Results show that friction coefficient is influenced by duration of rubbing, normal load and sliding velocity. In general, friction coefficient increases for a certain duration of rubbing and after that it remains constant for the rest of the experimental time. The obtained results reveal that friction coefficient decreases with the increase in normal load for SS 304 mating with smooth or rough mild steel counterface. On the other hand, it is also found that friction coefficient increases with the increase in sliding velocity. Moreover, wear rate increases with the increase in normal load and sliding velocity. The magnitudes of friction coefficient and wear rate are different depending on sliding velocity and normal load for both smooth and rough counterface pin materials. [ABSTRACT FROM AUTHOR]

Purpose – Solid thin films have been deposited on stainless steel 314 (SS 314) substrates in a chemical vapor deposition (CVD) reactor at different flow rates of natural gas mostly methane (CH4). The purpose of this paper was to investigate experimentally the variation of thin film deposition rate with the variation of gas flow rate. Design/methodology/approach – During experiment, the effect of gap between activation heater and substrate on the deposition rate has also been observed. To do so, a hot filament thermal CVD unit is used. The flow rate of natural gas varies from 0.5 to 2 l/min at normal temperature and pressure and the gap between activation heater and substrate varies from 4 to 6.5 mm. Findings – Results show that deposition rate on SS 314 increases with the increase of gas flow rate. It is also seen that deposition rate increases with the decrease of gap between activation heater and substrate within the observed range. These results are analyzed by dimensional analysis to correlate the deposition rate with gas flow rate, surface roughness and film thickness. In addition, friction coefficient and wear rate of SS 314 sliding against SS 304 under different normal loads are also investigated before and after deposition. The obtained results reveal that the values of friction coefficient and wear rate are lower after deposition than that of before deposition. Originality/value – In this study, thin film deposition rate on SS 314 was investigated using CVD. The obtained results were analyzed by dimensional analysis to correlate the deposition rate with gas flow rate, surface roughness and film thickness. The friction coefficient and wear rate of SS 314 were also examined before and after deposition. [ABSTRACT FROM AUTHOR]

Purpose – The present paper seeks to report the effect of duration of rubbing on friction coefficient for different polymer and composite materials. Variations of friction coefficient and wear rate with the normal load are also investigated experimentally when stainless steel (SS 304) pin slides on different types of materials such as cloth-reinforced ebonite (commercially known as gear fiber), glass fiber-reinforced plastic (glass fiber), nylon and polytetrafluoroethylene (PTFE). Design/methodology/approach – A pin on disc apparatus is designed and fabricated. During experiment, the rpm of test samples was kept constant and relative humidity was 70 percent. Findings – Studies have shown that the values of friction coefficient depend on applied load and duration of rubbing. It is observed that the values of friction coefficient decrease with the increase of normal load for glass fiber, nylon and PTFE. Different trend is observed for gear fiber, i.e. coefficient of friction increases with the increase of normal load. It is also found that wear rate increases with the increase of normal load for all the materials. The magnitudes of friction coefficient and wear rate are different for different materials. Practical implications – It is expected that the applications of these results will contribute to the design of different mechanical components of these materials. Originality/value – Within the observed range of applied normal load, the relative friction coefficient and wear rate of gear fiber, glass fiber, nylon and PTFE are experimentally investigated. [ABSTRACT FROM AUTHOR]