The wear and corrosion resistances are important in marine applications, especially when it comes to structural support components like bearings, bushes and blocks. The copper hybrid metal matrix components are the ne...The wear and corrosion resistances are important in marine applications, especially when it comes to structural support components like bearings, bushes and blocks. The copper hybrid metal matrix components are the new avenues explored in this front. A novel combination of alumina and graphite were considered as the reinforcements in a copper base for the development of a metal matrix composite.Power metallurgical techniques were used for the development of the MMC. The Vickers' s hardness value of 64.9 Hv has been observed by increasing the volume of alumina. Thermogravimetric analyses were carried out on material samples to estimate the exact sintering temperature and identified that 450-700℃ would be conducive. The TGA curves shows two step decomposition exists between 430 ℃-460 ℃. FT-IR analysis was done to confirm the peak values of the materials. FTIR exposed the peak value of 1600 cm^(-1) for alumina where as for Copper and graphite peak values have been 2840 cm^(-1) and 17260 cm^(-1) respectively. The potentio dynamic analysis was done to estimate the rate of corrosion on the samples. The sample with nano and micro reinforcements offered intensive resistance to corrosion. The presence of graphite minimized the weight loss of the samples during the corrosion test. Finally the wear rates of the samples were estimated using the Pin On Disc experimental setup. The samples with nano material reinforcement and with a maximum proportion of graphite exhibited a better wear rate of 1.52×10^(-12) m^2/kg under maximum load conditions.展开更多
Friction and wear studies enable the investigation of material interaction between two sliding surfaces in contact. In the present investigation, the coefficient of friction and the wear resistance of AISI 316 L parts...Friction and wear studies enable the investigation of material interaction between two sliding surfaces in contact. In the present investigation, the coefficient of friction and the wear resistance of AISI 316 L parts were studied under self-mating, dry sliding conditions using a pin-on-disc type configuration. The experiments were conducted at vacuum based high temperature pin-on-disc tribometer. The 4 mm diameter pin and 180 mm diameter disc were subjected to varying sliding velocities(0.5, 0.75 and 1.5 m/s) and were operated in 200, 400, 500 and 580 ℃ temperature at 600 Torr vacuum. The variation of specific wear rates with sliding velocities and different environmental conditions was studied. The morphology of sliding/rubbed surfaces was observed using Scanning Electron Microscope. In summary, it was found that a severe to mild wear transition occurred in sliding under operating conditions. Increased wear rates have been observed for 500 and 580 ℃ with increasing sliding velocity. Adhesive wear has been found to be predominant at 500 and 580 ℃ where as de-lamination has been observed at ambient temperature,200 and 400 ℃ in vacuum. The present paper also carried out the numerical analysis of the vibration behavior of AISI 316 L under thermal environment. Results revealed that at high temperature vibrational amplitude and natural frequency is significantly reduced. This can be attributed to the reduction in stiffness of the material at elevated temperatures. This high amplitude vibration during service can lead to high wear rate.展开更多
文摘The wear and corrosion resistances are important in marine applications, especially when it comes to structural support components like bearings, bushes and blocks. The copper hybrid metal matrix components are the new avenues explored in this front. A novel combination of alumina and graphite were considered as the reinforcements in a copper base for the development of a metal matrix composite.Power metallurgical techniques were used for the development of the MMC. The Vickers' s hardness value of 64.9 Hv has been observed by increasing the volume of alumina. Thermogravimetric analyses were carried out on material samples to estimate the exact sintering temperature and identified that 450-700℃ would be conducive. The TGA curves shows two step decomposition exists between 430 ℃-460 ℃. FT-IR analysis was done to confirm the peak values of the materials. FTIR exposed the peak value of 1600 cm^(-1) for alumina where as for Copper and graphite peak values have been 2840 cm^(-1) and 17260 cm^(-1) respectively. The potentio dynamic analysis was done to estimate the rate of corrosion on the samples. The sample with nano and micro reinforcements offered intensive resistance to corrosion. The presence of graphite minimized the weight loss of the samples during the corrosion test. Finally the wear rates of the samples were estimated using the Pin On Disc experimental setup. The samples with nano material reinforcement and with a maximum proportion of graphite exhibited a better wear rate of 1.52×10^(-12) m^2/kg under maximum load conditions.
文摘Friction and wear studies enable the investigation of material interaction between two sliding surfaces in contact. In the present investigation, the coefficient of friction and the wear resistance of AISI 316 L parts were studied under self-mating, dry sliding conditions using a pin-on-disc type configuration. The experiments were conducted at vacuum based high temperature pin-on-disc tribometer. The 4 mm diameter pin and 180 mm diameter disc were subjected to varying sliding velocities(0.5, 0.75 and 1.5 m/s) and were operated in 200, 400, 500 and 580 ℃ temperature at 600 Torr vacuum. The variation of specific wear rates with sliding velocities and different environmental conditions was studied. The morphology of sliding/rubbed surfaces was observed using Scanning Electron Microscope. In summary, it was found that a severe to mild wear transition occurred in sliding under operating conditions. Increased wear rates have been observed for 500 and 580 ℃ with increasing sliding velocity. Adhesive wear has been found to be predominant at 500 and 580 ℃ where as de-lamination has been observed at ambient temperature,200 and 400 ℃ in vacuum. The present paper also carried out the numerical analysis of the vibration behavior of AISI 316 L under thermal environment. Results revealed that at high temperature vibrational amplitude and natural frequency is significantly reduced. This can be attributed to the reduction in stiffness of the material at elevated temperatures. This high amplitude vibration during service can lead to high wear rate.
