Laser control melting of alumina surfaces with presence of B4C particles

Yilbaş, Bekir Sami; Al-Aqeeli, N.; Karataş, C.

doi:10.1016/j.jallcom.2012.05.105

Cited by 21 publications

(7 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Temperature remains above the melting temperature of the substrate material at the location where the laser beam irradiates the workpiece surface. Temperature decay along the peak temperature is gradual as compared to those reported for the laser straight scanning of the surfaces [32]. Consequently, conduction heat transfer from the high-temperature region toward the low-temperature region reduces the cooling rates in the surface region of the workpiece.…”

Section: Resultsmentioning

confidence: 74%

“…Hence, the cyclic behavior of von Mises stress replaces with the quasi-steady stress levels in the surface region with progressing time. Consequently, spiral motion of the laser scanning generates cyclic thermal loading in the surface region of the workpiece; however, the cyclic stress behavior replaces with the quasi-steady-like stress behavior in the surface region with progressing time, unlike the case observed with straight scanning of the laser beam at the surface during the treatment [31,32]. Figure 12 shows optical and SEM images of the top surfaces of the laser-treated workpiece.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Laser treatment of aluminum composite and investigation of thermal stress field

Yilbaş

Akhtar

Karataş

et al. 2016

Int J Adv Manuf Technol

Self Cite

View full text Add to dashboard Cite

Laser surface melting of hot pressed aluminum composite tile, consisting of 90 % aluminum and 10 % WC, is carried out. Temperature and stress fields developed in the laser-treated region are modeled and predicted using ABAQUS finite element code in line with the experimental conditions. The spiral motion of the laser beam is incorporated at the surface during the laser scanning. This arrangement provides self-annealing effect on the initially formed laser scanning tracks through heat conduction from the lately formed laser scanning tracks. Surface temperature predictions are validated through the thermocouple data. Morphological and metallurgical changes in the laser-treated layer are examined using optical and electron scanning microscopes. It is found that the cooling rates in the central region of the workpiece remain low because of the self-annealing effect of the lately formed laser scanning tracks. This, in turn, lowers von Mises stress levels in this region. Stress peaks are formed below the surface because of the high thermal strain formed in this region during the cooling cycle. The spiral scanning of the laser beam causes oscillating stress levels in the surface region of the laser-treated layer; in which case, its amplitude reduces with the progressing time. Laser-treated layer is free from cracks and crack networks, which is associated with the self-annealing effect of the lately formed laser scanning tracks.

show abstract

Section: Resultsmentioning

confidence: 74%

Section: Resultsmentioning

confidence: 99%

Laser treatment of aluminum composite and investigation of thermal stress field

Yilbaş

Akhtar

Karataş

et al. 2016

Int J Adv Manuf Technol

Self Cite

View full text Add to dashboard Cite

show abstract

“…The carbon film containing uniformly distributed 5% B 4 C was formed at the workpiece surface prior to the laser treatment process. The method applied for the formation of carbon film is similar to that presented in the previous study . The laser beam was scanned surface according to the parameters given in Table .…”

Section: Methodsmentioning

confidence: 99%

Laser surface treatment of high‐speed tool steel (AISI M2)

Yilbaş

Patel

Karataş

2012

Surface & Interface Analysis

Self Cite

View full text Add to dashboard Cite

High‐speed tool steel (AISI M2) surface is pre‐prepared to form a thin carbon film containing 5% B4C particles prior to laser treatment process. Morphological and metallurgical changes are examined in the treated layer using electron microscope, energy dispersive spectroscopy, and X‐ray diffraction. The microhardness and the residual stress formed at the treated surfaces are measured for samples with and without B4C particles. It is found that the micro‐stresses formed in the neighborhood of B4C particles at the treated surface contributed to the microhardness enhancement at the surface. This is associated with the mismatch of thermal expansion coefficients between B4C particles and the base alloy. The nitride phases are formed at the treated surface, which also contribute to the microhardness increase at the surface. Copyright © 2012 John Wiley & Sons, Ltd.

show abstract

“…The method applied for the formation of carbon film was similar to that presented in the previous study [14]. The carbon film containing uniformly distributed 5% B 4 C was formed at the workpiece surface prior to the laser treatment process.…”

Section: Experimental Producersmentioning

confidence: 99%