Surface roughness induced attenuation of reflected and transmitted ultrasonic waves

1987 ◽  
Vol 82 (1) ◽  
pp. 193-197 ◽  
Author(s):  
Peter B. Nagy ◽  
Laszlo Adler
Keyword(s):  
Surface Roughness ◽  
Ultrasonic Waves

Estimation of Internal Surface Roughness of Additively Manufactured Components Under Complex Conditions Using Artificial Intelligence and Measurements of Ultrasonic Backscatter

2021 ◽  
Author(s):  
Mohamed Subair Syed Akbar Ali ◽  
Mato Pavlovic ◽  
Prabhu Rajagopal
Keyword(s):  
Artificial Intelligence ◽  
Surface Roughness ◽  
Internal Surface ◽  
Side Surface ◽  
Ultrasonic Waves ◽  
Model Parameters ◽  
Ultrasonic Measurements ◽  
Neural Network Algorithm ◽  
X Ray Computed ◽  
Pulse Echo

Abstract Additive Manufacturing (AM) is increasingly being considered for fabrication of components with complex geometries in various industries such as aerospace and healthcare. Control of surface roughness of components is thus a crucial aspect for more widespread adoption of AM techniques. However, estimating the internal (or ‘far-side’) surface roughness of components is a challenge, and often requires sophisticated techniques such as X-ray computed tomography, which are difficult to implement online. Although ultrasound could potentially offer a solution, grain noise and inspection surface conditions complicate the process. This paper studies the feasibility of using Artificial Intelligence (AI) in conjunction with ultrasonic measurements for rapid estimation of internal surface roughness in AM components, using numerical simulations. In the first models reported here, a pulse-echo configuration is assumed, whereby a specimen sample with rough surfaces is insonified with bulk ultrasonic waves and the backscatter is used to generate A-scans. Simulations are carried out for various combinations of the model parameters, yielding a large number of such A-scans. A neural network algorithm is then created and trained on a subset of the datasets so generated using simulations, and later used to predict the roughness from the rest. The results demonstrate the immense potential of this approach in inspection automation for rapid roughness assessments in AM components, based on ultrasonic measurements.

scholarly journals Effect of surface roughness on ultrasonic inspection of electron beam melting ti‐6AL‐4V

2019 ◽  
Vol 3 (2) ◽  
pp. 131-141
Author(s):  
Evan Hanks ◽  
Anthony Palazotto ◽  
David Liu
Keyword(s):  
Surface Roughness ◽  
Electron Beam ◽  
New Technology ◽  
High Surface ◽  
Ultrasonic Inspection ◽  
Ultrasonic Waves ◽  
Aviation Industry ◽  
Sound Waves ◽  
Machined Surface ◽  
Content Type

Purpose Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of electron beam melted (EBM) additively manufactured Ti-6Al-4V. Additive manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include aircraft battle damage repair (ABDR), small batch manufacturing to fill supply gaps and replacement for obsolete parts. This paper aims to assess the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM-manufactured Ti-6Al-4V. Additively manufactured EBM products have a high surface roughness in “as-manufactured” condition which is an artifact of the manufacturing process. The surface roughness is known to affect the results of ultrasonic inspections. Experimental data from this research demonstrate the ability of ultrasonic inspections to identify imbedded flaws as small as 0.51 mm at frequencies of 2.25, 5 and 10 MHz through a machined surface. Detection of flaws in higher surface roughness samples was increased at a frequency of 10 MHz opposed to both lower frequencies tested. Design/methodology/approach The approach is to incorporate ultrasonic waves to identify flaws in an additive manufactured specimen Findings A wave frequency of 10 MHz gave good results in finding flaws even with surface roughness present. Originality/value To the best of the authors’ knowledge, this was the first attempt that was able to identify small flaws using ultrasonic sound waves in which surface roughness was present.

IMPROVEMENT OF SURFACE ROUGHNESS DURING TURNING OF PRE-HEATED MILD STEEL USING VOICE ACTIVATED ULTRASONIC WAVES

2015 ◽  
Vol 76 (6) ◽  
Author(s):  
Anayet U Patwari ◽  
Mohammad Ahsan Habib ◽  
Md. S. I. Chowdhury ◽  
Afzal H. Neelav ◽  
Md. Sharfat Latif ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Mild Steel ◽  
Ultrasonic Waves ◽  
Great Promise ◽  
Hybrid Technique ◽  
Average Surface Roughness ◽  
Sound Waves ◽  
Turning Process ◽  
Machined Surface ◽  
Average Surface

Surface roughness represents the dimensional accuracy of the finished product and is one of the most important quality parameters of the finished product. For improvement of the surface quality several techniques like magnetic field, ultrasonic assisted turning and so on has been introduced. Ultrasonically Assisted Turning has been one of the techniques which showed great promise. It is a hybrid technique based on superimposition of ultrasonic vibration on a movement of a cutting tool in turning process. In this paper, a new technique using the concept of voice activated mode generated ultrasonic smart waves has been proposed and adopted with an aim to improve average surface roughness of the preheated machined surface of mild steel. Externally voice activated ultrasonic sound waves were applied during turning process of preheated mild steel and its effect on average surface roughness was studied. Experimentations were carried out under different ultrasonic frequencies to determine the surface roughness to the best degree possible. The experimental results showed significant improvements in surface roughness in preheated machined products. 

Roughness measurements of nonlinear optical polymer films by scanning tunneling microscopy

1989 ◽  
Vol 47 ◽  
pp. 22-23
Author(s):  
I. H. Musselman ◽  
R.-T. Chen ◽  
P. E. Russell
Keyword(s):  
Surface Roughness ◽  
Scanning Tunneling Microscopy ◽  
Nonlinear Optical ◽  
Polymer Surface ◽  
Light Extinction ◽  
Scanning Tunneling ◽  
Silicon Substrates ◽  
Tunneling Microscopy ◽  
Optical Polymer ◽  
Total Light

Scanning tunneling microscopy (STM) has been used to characterize the surface roughness of nonlinear optical (NLO) polymers. A review of STM of polymer surfaces is included in this volume. The NLO polymers are instrumental in the development of electrooptical waveguide devices, the most fundamental of which is the modulator. The most common modulator design is the Mach Zehnder interferometer, in which the input light is split into two legs and then recombined into a common output within the two dimensional waveguide. A π phase retardation, resulting in total light extinction at the output of the interferometer, can be achieved by changing the refractive index of one leg with respect to the other using the electrooptic effect. For best device performance, it is essential that the NLO polymer exhibit minimal surface roughness in order to reduce light scattering. Scanning tunneling microscopy, with its high lateral and vertical resolution, is capable of quantifying the NLO polymer surface roughness induced by processing. Results are presented below in which STM was used to measure the surface roughness of films produced by spin-coating NLO-active polymers onto silicon substrates.

Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

1996 ◽  
Vol 54 ◽  
pp. 866-867
Author(s):  
H. Kinney ◽  
M.L. Occelli ◽  
S.A.C. Gould
Keyword(s):  
Surface Roughness ◽  
Zeolite Y ◽  
Atomic Level ◽  
Microporous Structure ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
Roughness Measurements ◽  
Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

"Escherichia coli-milk" Biofilm Removal from Stainless Steel Surfaces: Synergism between Ultrasonic Waves and Enzymes

Biofouling ◽  
2003 ◽  
Vol 19 (3) ◽  
pp. 159-168 ◽  
Author(s):  
Nadia Oulahal- Lagsir ◽  
Adele Martial- Gros ◽  
Marc Bonneauc ◽  
Loic Bluma
Keyword(s):  
Escherichia Coli ◽  
Stainless Steel ◽  
Ultrasonic Waves ◽  
Biofilm Removal ◽  
Steel Surfaces

" Escherichia coli -milk" Biofilm Removal from Stainless Steel Surfaces: Synergism between Ultrasonic Waves and Enzymes

Biofouling ◽  
2003 ◽  
Vol 19 (3) ◽  
pp. 159-168 ◽  
Author(s):  
NADIA OULAHAL-LAGSIR ◽  
ADELE MARTIAL-GROS ◽  
MARC BONNEAU ◽  
LOIC BLUM
Keyword(s):  
Escherichia Coli ◽  
Stainless Steel ◽  
Ultrasonic Waves ◽  
Biofilm Removal ◽  
Steel Surfaces
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