Ni-Cr/h-BN self-lubricating composities were prepared by powder metallurgy (P/M) method.The effects of hexagonal boron nitride (h-BN) content on the mechanical and tribological properties of the Ni-Cr/h-BN composites ...Ni-Cr/h-BN self-lubricating composities were prepared by powder metallurgy (P/M) method.The effects of hexagonal boron nitride (h-BN) content on the mechanical and tribological properties of the Ni-Cr/h-BN composites were investigated.The corresponding frictional models were established to analyze the formation of the lubricant h-BN films on the surfaces of the Ni-Cr/h-BN composites.The results show that,when the content of h-BN increases from 5% to 15% (mass fraction),the bending strength of the Ni-Cr/h-BN composite decreases from 96.670 MPa to 17.319 MPa,and the hardness (HB) decreases from 33 to 14.The friction coefficient of the Ni-Cr/h-BN composite decreases firstly from 0.385 to 0.216,and then increases to 0.284,while the wear rate decreases firstly from 4.14×10-9 kg/(N·m) to 1.35×10-9 kg/(N·m),then increases to 2.36×10-9 kg/(N·m).The best comprehensive mechanical and tribological properties can be obtained between 10% and 12% h-BN addition.展开更多
The wear behavior of multi-walled carbon nano-tubes(MWCNTs)reinforced copper metal matrix composites(MMCs)processed through powder metallurgy(PM)route was focused on and further investigated for varying MWCNT quantity...The wear behavior of multi-walled carbon nano-tubes(MWCNTs)reinforced copper metal matrix composites(MMCs)processed through powder metallurgy(PM)route was focused on and further investigated for varying MWCNT quantity viaexperimental,statistical and artificial neural network(ANN)techniques.Microhardness increases with increment in MWCNTquantity.Wear loss against varying load and sliding distance was analyzed as per L16orthogonal array using a pin-on-disctribometer.Process parameter optimization by Taguchi’s method revealed that wear loss was affected to a greater extent by theintroduction of MWCNT;this wear resistant property of newer composite was further analyzed and confirmed through analysis ofvariance(ANOVA).MWCNT content(76.48%)is the most influencing factor on wear loss followed by applied load(12.18%)andsliding distance(9.91%).ANN model simulations for varying hidden nodes were tried out and the model yielding lower MAE valuewith3-7-1network topology is identified to be reliable.ANN model predictions with R value of99.5%which highly correlated withthe outcomes of ANOVA were successfully employed to investigate individual parameter’s effect on wear loss of Cu?MWCNTMMCs.展开更多
基金Project(MKPT-03-182) supported by the Ministry of Science and Technology of China
文摘Ni-Cr/h-BN self-lubricating composities were prepared by powder metallurgy (P/M) method.The effects of hexagonal boron nitride (h-BN) content on the mechanical and tribological properties of the Ni-Cr/h-BN composites were investigated.The corresponding frictional models were established to analyze the formation of the lubricant h-BN films on the surfaces of the Ni-Cr/h-BN composites.The results show that,when the content of h-BN increases from 5% to 15% (mass fraction),the bending strength of the Ni-Cr/h-BN composite decreases from 96.670 MPa to 17.319 MPa,and the hardness (HB) decreases from 33 to 14.The friction coefficient of the Ni-Cr/h-BN composite decreases firstly from 0.385 to 0.216,and then increases to 0.284,while the wear rate decreases firstly from 4.14×10-9 kg/(N·m) to 1.35×10-9 kg/(N·m),then increases to 2.36×10-9 kg/(N·m).The best comprehensive mechanical and tribological properties can be obtained between 10% and 12% h-BN addition.
文摘The wear behavior of multi-walled carbon nano-tubes(MWCNTs)reinforced copper metal matrix composites(MMCs)processed through powder metallurgy(PM)route was focused on and further investigated for varying MWCNT quantity viaexperimental,statistical and artificial neural network(ANN)techniques.Microhardness increases with increment in MWCNTquantity.Wear loss against varying load and sliding distance was analyzed as per L16orthogonal array using a pin-on-disctribometer.Process parameter optimization by Taguchi’s method revealed that wear loss was affected to a greater extent by theintroduction of MWCNT;this wear resistant property of newer composite was further analyzed and confirmed through analysis ofvariance(ANOVA).MWCNT content(76.48%)is the most influencing factor on wear loss followed by applied load(12.18%)andsliding distance(9.91%).ANN model simulations for varying hidden nodes were tried out and the model yielding lower MAE valuewith3-7-1network topology is identified to be reliable.ANN model predictions with R value of99.5%which highly correlated withthe outcomes of ANOVA were successfully employed to investigate individual parameter’s effect on wear loss of Cu?MWCNTMMCs.
