Measurement Accuracy Problems of the Surface Texture Parameters

2017 ◽  
Vol 260 ◽  
pp. 227-234
Author(s):  
Natalija Bulaha ◽  
Janis Lungevics ◽  
Janis Rudzitis

In this scientific article the recommendations for a three-dimensional surface roughness parameters determination of mechatronics elements are developed. First of all, the measurements for surface with irregular roughness were made, what led to the determination of a 3D roughness correlation function. On that basis correlation interval in two perpendicular treatment directions was calculated and associated with number of surface roughness uncorrelated points. Secondly, the surface roughness step parameters evaluation precision in two mutually perpendicular directions was analysed. Particular attention was paid to the roughness average step RSm in the treatment longitudinal direction. As a result, the recommendations for a 3D roughness parameters determination were prepared.

2010 ◽  
Vol 132 (11) ◽  
Author(s):  
Lars Vedmar

Hobbing is a common manufacturing method when producing helical, involute gears. In order to give the manufactured gear a controlled surface smoothness, a method to, very accurately, determine the achieved surface geometry is needed. In this report, the cutting surfaces of the tool, of which the cutting edges are the boundaries, are assumed to be plane in arbitrary directions. They are mathematically described using parametric and analytically differentiable functions. These functions give the possibility to determine the geometry of the three-dimensional surface of the manufactured gear, without any additional numeric approximations. By comparing this surface with the smooth surface of an ideal gear, the roughness of the surface can be determined. An example is given in which the surface topology and the characteristic surface roughness parameters are determined.


2013 ◽  
Vol 274 ◽  
pp. 174-178 ◽  
Author(s):  
Bo Liu ◽  
Hai Yin Yu ◽  
Fan Ye ◽  
Jian Ying Guo

With the improvement of mechanical processing automatic level, the measurement of the surface roughness requires the ever-increasing demands, including the improvement of measurement methods, improve measurement accuracy and roughness parameters assessed. Around these requirements, this paper is the research to 3D surface roughness parameters, gives the method to determine the datum and 3D roughness assessment parameters.


Author(s):  
Kang Liu ◽  
Titan C. Paul ◽  
Leo A. Carrilho ◽  
Jamil A. Khan

The experimental investigations were carried out of a pressurized water nuclear reactor (PWR) with enhanced surface using different concentration (0.5 and 2.0 vol%) of ZnO/DI-water based nanofluids as a coolant. The experimental setup consisted of a flow loop with a nuclear fuel rod section that was heated by electrical current. The fuel rod surfaces were termed as two-dimensional surface roughness (square transverse ribbed surface) and three-dimensional surface roughness (diamond shaped blocks). The variation in temperature of nuclear fuel rod was measured along the length of a specified section. Heat transfer coefficient was calculated by measuring heat flux and temperature differences between surface and bulk fluid. The experimental results of nanofluids were compared with the coolant as a DI-water data. The maximum heat transfer coefficient enhancement was achieved 33% at Re = 1.15 × 105 for fuel rod with three-dimensional surface roughness using 2.0 vol% nanofluids compared to DI-water.


2018 ◽  
Vol 65 (3) ◽  
pp. 115-121
Author(s):  
Zorana Lanc ◽  
Milan Zeljković ◽  
Aleksandar Živković ◽  
Branko Štrbac ◽  
Miodrag Hadžistević

Abstract This paper presents the experimental determination of the dependence of emissivity of brass on surface roughness and temperature. The investigation was conducted using the infrared thermographic technique on brass alloy C27200 workpieces with different degrees of surface roughness, during the continuous cooling process. The results obtained showed that the emissivity of the chosen brass alloy increases with greater surface roughness and decreases during the cooling process, its value ranging from 0.07 to 0.19. It was concluded that surface roughness has a greater influence on the increase of the emissivity at higher temperatures, which can be seen in the three-dimensional infrared images. Multiple regression analysis confirmed a strong correlation between the examined parameters and the emissivity, and an original multiple regression model was determined.


2019 ◽  
Vol 6 (9) ◽  
pp. 190915 ◽  
Author(s):  
Hanna E. Burton ◽  
Rachael Cullinan ◽  
Kyle Jiang ◽  
Daniel M. Espino

The aim of this study was to investigate the multiscale surface roughness characteristics of coronary arteries, to aid in the development of novel biomaterials and bioinspired medical devices. Porcine left anterior descending coronary arteries were dissected ex vivo , and specimens were chemically fixed and dehydrated for testing. Surface roughness was calculated from three-dimensional reconstructed surface images obtained by optical, scanning electron and atomic force microscopy, ranging in magnification from 10× to 5500×. Circumferential surface roughness decreased with magnification, and microscopy type was found to influence surface roughness values. Longitudinal surface roughness was not affected by magnification or microscopy types within the parameters of this study. This study found that coronary arteries exhibit multiscale characteristics. It also highlights the importance of ensuring consistent microscopy parameters to provide comparable surface roughness values.


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