Experimental results are presented to illustrate that there exists a unique window of opportunity for eddy current NDE of residual stress in surface-treated nickel-base superalloys. In light of its frequency-dependent penetration depth, the measurement of eddy current conductivity has been suggested as a possible means to allow the nondestructive evaluation of subsurface residual stresses in su...

background: an increase in surface roughness of ceramics may decrease strength and affect the clinical success of ceramic restorations. however, little is known about the effect of acidic agents on ceramic restorations. the aim of this study was to evaluate the surface roughness of dental ceramics after being immersed in acidic agents.     methods: eighty-three ceramic disk specimens (12.0 mm i...

A fuzzy-nets based in-process adaptive surface roughness control (FNASRC) system was developed in this research. The FNASRC system was able to adapt cutting parameters in-process and in a real time fashion to improve the surface roughness of machined parts when the surface roughness quality was not meeting customer requirements in the end milling operations. The FNASRC system was comprised of t...

One of the most important resources available in the field of fluid mechanics, the Moody Chart gives Darcy friction factor as a function of Reynolds number and relative roughness. The experimentalists who generated the data correlated in the Moody Chart, however, roughened pipe surfaces by coating their internal surfaces with a monolayer of sand, the pipe wall roughness being defined as the ave...

Surfaces of metal sheets initially contain high frequency, low amplitude roughness components imparted during the rolling process. When plastic deformation is imposed, the amplitude of these free surface components increases, producing various kinds of morphological features including randomness, periodicity and waviness. The features often control key functional aspects of a metal surface, suc...

in this paper, the amount of wasted heat from different parts of a 12 liter compression ignition engine and their potential for waste heat recovery were investigated. then, two-stage configuration of organic rankine cycle was introduced for simultaneous heat recovery from exhaust gases and coolant. finally, parameters like hybrid generated power, engine thermal efficiency and brake specific fue...

Deliberate modification of bottom roughness, including smoothing to eliminate centimetre scale natural roughness and raking to induce quasiperiodic roughness, was investigated using diver observations, quantification of bottom roughness from stereo photography, and measurement of acoustic backscattering strength. At 40 kHz, raking perpendicular to the acoustic line-of-sight with a tine spacing ...

The determination of the possibility for reduction friction coefficient ceramic parts from silicon carbide by pulse-periodic treatment with an ultraviolet nanosecond laser was carried out in framework this research. gas-dynamic seal compressor rotor gas-turbine engine after hot isostatic pressing and mechanical exposed to surface microstructuring a mode. For experimental investigations, maximum...

The supercharger is intended for heating a fluid (gaseous helium or gaseous nitrogen) used the pressurization of fuel tanks oxidizer and propellant rocket engine. heated with generator gas downstream turbine. A increased channel surface roughness was made according to an additive technology. High one features producing parts by selective laser melting. article presents method calculating heat t...