In the present study, bond-coats for thermal barrier coatings were deposited via air plasma spraying(APS) techniques onto Inconel 800 and Hastelloy C-276 alloy substrates. Scanning electron microscopy(SEM), transm...In the present study, bond-coats for thermal barrier coatings were deposited via air plasma spraying(APS) techniques onto Inconel 800 and Hastelloy C-276 alloy substrates. Scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), and atomic force microscopy(AFM) were used to investigate the phases and microstructure of the as-sprayed, APS-deposited Co Ni Cr Al Y bond-coatings. The aim of this work was to study the suitability of the bond-coat materials for high temperature applications. Confirmation of nanoscale grains of the γ/γ′-phase was obtained by TEM, high-resolution TEM, and AFM. We concluded that these changes result from the plastic deformation of the bond-coat during the deposition, resulting in Co Ni Cr Al Y bond-coatings with excellent thermal cyclic resistance suitable for use in high-temperature applications. Cyclic oxidative stability was observed to also depend on the underlying metallic alloy substrate.展开更多
The work done in this work deals with the efficacy of cutting parameters on surface of EN-8 alloy steel.For knowing the optimal effects of cutting parameters response surface methodology was practiced subjected to cen...The work done in this work deals with the efficacy of cutting parameters on surface of EN-8 alloy steel.For knowing the optimal effects of cutting parameters response surface methodology was practiced subjected to central composite design matrix.The motive was to introduce an interaction among input parameters,i.e.,cutting speed,feed and depth of cut and output parameter,surface roughness.For this,second order response surface model was modeled.The foreseen values obtained were found to be fairly close to observed values,showed that the model could be practiced to forecast the surface roughness on EN-8 within the range of parameter studied.Contours and 3-D plots are generated to forecast the value of surface roughness.It was revealed that surface roughness decreases with increases in cutting speed and it increases with feed.However,there were found negligible or almost no implication of depth of cut on surface roughness whereas feed rate affected the surface roughness most.For lower surface roughness,the optimum values of each one were also evaluated.展开更多
基金provided by Technical Education Quality Improvement Programme-Ⅱ(TEQIP-Ⅱ)at MNNIT Allahabad
文摘In the present study, bond-coats for thermal barrier coatings were deposited via air plasma spraying(APS) techniques onto Inconel 800 and Hastelloy C-276 alloy substrates. Scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), and atomic force microscopy(AFM) were used to investigate the phases and microstructure of the as-sprayed, APS-deposited Co Ni Cr Al Y bond-coatings. The aim of this work was to study the suitability of the bond-coat materials for high temperature applications. Confirmation of nanoscale grains of the γ/γ′-phase was obtained by TEM, high-resolution TEM, and AFM. We concluded that these changes result from the plastic deformation of the bond-coat during the deposition, resulting in Co Ni Cr Al Y bond-coatings with excellent thermal cyclic resistance suitable for use in high-temperature applications. Cyclic oxidative stability was observed to also depend on the underlying metallic alloy substrate.
文摘The work done in this work deals with the efficacy of cutting parameters on surface of EN-8 alloy steel.For knowing the optimal effects of cutting parameters response surface methodology was practiced subjected to central composite design matrix.The motive was to introduce an interaction among input parameters,i.e.,cutting speed,feed and depth of cut and output parameter,surface roughness.For this,second order response surface model was modeled.The foreseen values obtained were found to be fairly close to observed values,showed that the model could be practiced to forecast the surface roughness on EN-8 within the range of parameter studied.Contours and 3-D plots are generated to forecast the value of surface roughness.It was revealed that surface roughness decreases with increases in cutting speed and it increases with feed.However,there were found negligible or almost no implication of depth of cut on surface roughness whereas feed rate affected the surface roughness most.For lower surface roughness,the optimum values of each one were also evaluated.