Preferred Language
Articles
/
alkej-254
Laser Peening on Aluminum Alloy 7049 Using Black Paint Surface Coating
...Show More Authors

Abstract

Black paint laser peening (bPLP) technique is currently applied for many engineering materials , especially for aluminum alloys due to high improvement in fatigue life and strength . Constant and variable   bending fatigue tests have been performed at RT and stress ratio R= -1 . The results of the present  work observed that the significance of the surface work hardening which generated high negative residual stresses in bPLP specimens .The fatigue life  improvement factor (FLIF)  for bPLP constant fatigue behavior was from 2.543 to 3.3 compared to untreated  fatigue and the increase in fatigue strength at 107 cycle was 21% . The bPLP cumulative fatigue life behavior was improved by 1.786 at L-H and 1.55 at H-L due to black paint coating .

 Keywords: Constant and variable fatigue behavior , Black paint laser peening , 7049 Al- alloy .

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Dec 13 2005
Journal Name
Iraqi Journal Of Laser
Clinical Observation and Performance of High Power Diode Laser in the Treatment of Oral Lesions
...Show More Authors

In this work, oral lesions belong to 17 patients, 7 males and 10 females. Their ages range between 15 and 45 years. Follow up was conducted after one day, 7 days, 14 days, one month, and finally 3 months postoperatively. The study lasted for 1.5 year. Surgical diode laser with wavelength of 810 ± 20 nm, with two power levels of 10 and 15 W were used in contact and in non-contact mode via optical fiber. The postoperative outcome revealed; greater haemostatic capability, dry, sealed wound and noticeable lack in pain sensation

View Publication Preview PDF
Publication Date
Sun Jan 01 2006
Journal Name
Journal Of Cosmetic And Laser Therapy
Use of the pulsed infrared diode laser (904 nm) in the treatment of alopecia areata
...Show More Authors

View Publication
Scopus (53)
Crossref (56)
Scopus Crossref
Publication Date
Sun Sep 06 2009
Journal Name
Baghdad Science Journal
Band Gap Energy for SiC Thin Films Prepared By TEACO2 Laser Irradiated With Nuclear Radiation
...Show More Authors

The effect of high energy radiation on the energy gap of compound semiconductor Silicon Carbide (SiC) are viewed. Emphasis is placed on those effects which can be interpreted in terms of energy levels. The goal is to develop semiconductors operating at high temperature with low energy gaps by induced permanent damage in SiC irradiated by gamma source. TEACO2 laser used for producing SiC thin films. Spectrophotometer lambda - UV, Visible instrument is used to determine energy gap (Eg). Co-60, Cs-137, and Sr-90 are used to irradiate SiC samples for different time of irradiation. Possible interpretation of the changing in Eg values as the time of irradiation change is discussed

View Publication Preview PDF
Crossref
Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Design and Comparative Study of a one and Two Stage Blumlein Circuit TEA Nitrogen Laser
...Show More Authors

Two Prototypes of Transversely Excited at atmospheric pressure (TEA) Nitrogen laser systems (One Stage Blumlein Circuit and Two Stage Blumlein Circuit) were fabricated and operated. High voltage power supply with variable operating voltage (0-20 kv) and operating current (1-3A) was built and tested successfully. The gas flow rate of 15 L/ min and 10 L/ min for OSBC and TSBC was used. The performance of the fabricated systems was studied extensively reaching to the optimum operating conditions. The obtained laser output energy for the first system has linear relationship with the applied voltage. The maximum output energy was about (1.14 mJ) with (10.40) ns pulse duration and the half-wave divergence angle was about (0.1455 m rad). In the

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 18 2020
Journal Name
Baghdad Science Journal
Cr2O3:TiO2 Nanostructure Thin Film Prepared by Pulsed Laser Deposition Technique as NO2 Gas Sensor
...Show More Authors

Pulsed laser deposition (PLD) technique was applied to prepared Chromium oxide (Cr2O3) nanostructure doped with Titanium oxide (TiO2) thin films at different concentration ratios 3,5,7 and 9 wt % of TiO2. The effect of TiO2 dopant on the average size of crystallite of the synthesized nanostructures was examined by X-ray diffraction. The morphological properties were discussed using atomic force microscopy(AFM). Observed optical band gap value ranged from 2.68 eV to 2.55 eV by ultraviolet visible(UV-Vis.) absorption spectroscopy with longer wave length shifted  in comparison with that of the bulk Cr2O3 ~3eV. This indicated that the synthesized samples a

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (9)
Scopus Clarivate Crossref
Publication Date
Sun Jan 25 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Acceleration of canine movement by laser assisted flapless corticotomy [An innovative approach in clinical orthodontics]
...Show More Authors

Background: Corticotomy-assisted orthodontic treatment is done to induce a state of increased tissue turnover and transient osteopenia, which is followed by a faster rate of orthodontic tooth movement. It considered as an adjunct treatment option for orthodontic treatment of adults. The aim of this Study was to elucidate the effectiveness of a new surgical approach for acceleration of maxillary canine retraction in human with laser assisted flapless corticotomy and evaluate its effect on vitality of pulp and gingival sulcus depth. Materials and methods: the sample comprised of 15 Iraqi patients (9 females and 6 males; mean age 21.7), who were required extraction for their maxillary first premolars followed by retraction of the canines as pa

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 10 2009
Journal Name
Iraqi Journal Of Laser
Diagnosis and Treatment of Cervical Intraepithelial Neoplasia with Carbon Dioxide Laser Therapy in Selected Patients
...Show More Authors

Female infection with HPV (human papilla virus) has been established as an essential cause of CIN (cervical intraepithelial neoplasia). The danger of transformation from CIN to frank malignancy should be considered. Objective: The goal of this study is to evaluate the effectiveness of CO2 laser vaporization of ectocervical lesion high grade squamous intraepithelial lesion (HGSIL). Patients and Methods: Four Female out of 150 affected with HGSIL lesions were submitted to CO2 laser vaporization and followed up in 4 months later, and 10 women with HGSIL lesion submitted to electrocautery diathermy for the comparison. Results: Among women treated by CO2 laser vaporization, 3 women had negative results (clear cervix), at 4 months follow up; o

... Show More
View Publication Preview PDF
Publication Date
Thu Jun 01 2023
Journal Name
Australian Dental Journal
Debonding of LDSVs utilising Er,Cr:YSGG laser irradiation with fractional technique: an in vitro study
...Show More Authors

Scopus (5)
Scopus
Publication Date
Sun Mar 01 2020
Journal Name
International Journal For Light And Electron Optics
Optical properties of Ag-doped nickel oxide thin films prepared by pulsed-laser deposition technique
...Show More Authors

In this work, pure and Ag-doped nickel oxide (NiO) thin films were deposited on glass substrates with different dopant concentrations (0.1, 0.2, 0.3 and 0.4 wt.%) by pulsed-laser deposition (PLD) technique at room temperature. These films were annealed at temperature of 450 °C. The structural and optical properties of the prepared thin films were studied. It was found that annealing process has lead to increase the transmittance of the deposited films. Also, the transmittance was found to increase with doping concentration of silver in the deposited NiO films. The optical energy gap was decreased from 3.5 to 3.2 eV as the doping concentration was increased to 0.4 %.

View Publication
Scopus (30)
Crossref (28)
Scopus Clarivate Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Iraqi Journal Of Physics
Influence of working pressure and lasing energy of Al plasma in laser-induced breakdown spectroscopy
...Show More Authors

Aluminum plasma was generated by the irradiation of the target
with Nd: YAG laser operated at a wavelength of 1064 nm. The
effect of laser power density and the working pressure on spectral
lines generating by laser ablation, were detected by using optical
spectroscopy. The electron density was measured using the Stark
broadening of aluminum lines and the electron temperature by
Boltzmann plot method it is one of the methods that are used. The
electron temperature Te, electron density ne, plasma frequency
and Debye length increased with increasing the laser peak
power. The electron temperature decrease with increasing gas
pressure.

View Publication Preview PDF
Crossref (1)
Crossref