Influence of Material Coating on Stress Measurement by Ultrasonic Surface Wave (Part 1)

Ultrasonic surface wave have been implemented to measure or predict the existing stress on material. Surface wave velocity shows linearly increase with stress applied in material. However, various applications were coated their surfaces with high corrode resistance material for example paint or aluminum thermal sprays. It may cause the change of the velocity of surface wave and lead to miss prediction. This paper presents the effect of material coating on surface wave velocity and its attenuations. Paint and Aluminum thermal spray coated on low carbon steel graded S420 (EN 10025 Standard) in the range of 100-500 micron. Through transmission ultrasonic surface wave was applied to measure the velocities change. Their frequencies are 2.25 and 5 MHz respectively. It was found that coating thickness show effect on sound velocity and sound wave attenuation. The benefit is to know the effect of coating and to approve the accuracy of stress measurement by ultrasonic wave.

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Frequency Dependence of Ultrasonic Wave Attenuation in Armco Iron and Low-Carbon Steel

Journal of Applied Physics ◽

10.1063/1.2000437 ◽

1961 ◽

Vol 32 (3) ◽

pp. S280-S281 ◽

Cited By ~ 3

Author(s):

U. M. Martius ◽

W. J. Bratina

Keyword(s):

Carbon Steel ◽

Frequency Dependence ◽

Ultrasonic Wave ◽

Armco Iron ◽

Wave Attenuation ◽

Low Carbon Steel ◽

Low Carbon

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To Investigate the Effect of Heat Treatment on Low Carbon Steel Corrosion Behavior

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i3.20.20584 ◽

2018 ◽

Vol 7 (3.20) ◽

pp. 412

Author(s):

Azhar Wahab Abdalrhem ◽

Ali Jaber Naeemah ◽

Makki Noori jawad

Keyword(s):

Heat Treatment ◽

Carbon Steel ◽

Corrosion Rate ◽

Corrosion Behavior ◽

Low Carbon Steel ◽

Steel Corrosion ◽

Optical Microscope ◽

Polarization Measurement ◽

Material Surface ◽

Low Carbon

This work was to investigating the corrosion behavior of low carbon steel in a salt solution of 3.5wt% NaCl after undergoing two different types of heat treatment at 960 ºC in a furnace. The material of low carbon steel was cut into nine small pieces under three groups A, B and C, without heated annealing and hardening heat treatment respectively. The heat treatment was at temperature 960ºC. The hardness of the sample as received will be 203 kg/mm2 while after hardening the hardness was increased. The sample was mounted using hot and cold mounting. The microstructure and surface morphology was observed by using Scanning Electron Microscope (SEM) and Optical Microscope (OM) after grinding, polishing and etching on the sample. In group A cementite can be observed clearly on pearlite on the surface before corrosion test. After four days soaking in 3.5 wt% NaCl solution was observed all cementite and pearlite will be transformed to austenite with the remnants of cementite make the surface unstable hence increases the initial corrosion. After four days soaking when the cementite is oxidized and a thick film of corrosion product covers the material surface. The formation of Martensite due to quenching and rapid cooling in group C sample increases the corrosion rate from 0.072 mpy to 0.302 due to decreased of corrosion potential from -572 mV to -639 mV after four days soaking. The corrosion rate of each sample was measured by using electrochemical polarization measurement and Tafel extrapolation technique. From previous result, it was observed that samples which had undergone annealing mode of heat treatment turned out to be the ones with the best corrosion resistance.

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Influence of Grain Size and Rolling Direction on Stress Measurement by Ultrasonic Surface Wave (Part 2)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.717.221 ◽

2013 ◽

Vol 717 ◽

pp. 221-226 ◽

Cited By ~ 1

Author(s):

Pavaret Preedawiphat ◽

Asa Prateepasen ◽

Mai Noipitak

Keyword(s):

Grain Size ◽

Surface Wave ◽

Sound Velocity ◽

Ultrasonic Wave ◽

Wave Velocity ◽

Stress Measurement ◽

Rolling Direction ◽

Material Type ◽

Grain Sizes ◽

Surface Wave Velocity

Stress measurement based on the change of ultrasonic surface wave has been accepted to find out residual or existing stress on material. This paper shows the effect of rolling direction and grain size of material on surface wave velocity and energy attenuation. Different grain and rolling direction of material type SS 400, S420 and A516 were selected to test its effect. Three grain sizes of each material were varied by normalizing process at three temperature range (no heating, 850°C, 980°C and 1160°C). Through transmission ultrasonic surface wave, frequencies 2.25 and 5 MHz, were applied and recorded the velocity and attenuation of the response. The results show that rolling direction and grain size slightly effect on attenuation of ultrasonic wave but unaffected on sound velocity. Its outcome was compared with the effect of the material coating.

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