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Lasers are integral to numerous applications in our daily lives, with one of their notable uses being the ablation of materials to generate plasma, which in turn produces X-rays with a variety of applications. This study investigates the generation of hard X-rays from Aluminum Antimonide (AlSb) plasma, induced by a Q-switched Nd: YAG laser operating at 1064nm with a pulse duration of 9–14ns and a peak power of 1.1MW. The AlSb target was selected due to its unique electronic structure and high atomic number, which are advantageous for efficient X-ray generation. At a tight focus, the laser produced a spot size of 11.8 micrometers, achieving an intensity of 10¹² W/cm${}^{-2}$, to study the transmission of hard X-rays both in a vacuum environment with a pressure of 10${}^{-3}$ torr and in air at atmospheric pressure. A Photo Multiplier Tube (PMT) was employed to detect the transmitted hard X-rays, which were filtered using a 10 $\mu$m-thick Al filter. The fundamental mechanisms behind the emission of hard X-rays from laser-induced AlSb plasma were explored. Plasma plume expansion and the energy of the emitted radiation were found to depend on the number of laser pulses and the ambient pressure. The intensity of the plasma plume was observed to be inversely proportional to the ambient pressure and directly proportional to the number of laser pulses fired. Plasma confinement under high pressures was also examined. Time-resolved studies of the hard X-ray emission contributed to the analysis. The relationship between different laser shots and the current, voltage, and energy of the hard X-rays, as well as their inverse proportionality to ambient pressure, was quantified. At an ambient pressure of 10${}^{-3}$ torr, the dynamics of the AlSb plasma plume were observed. The surface morphology of the laser-irradiated AlSb target was also analyzed, revealing unique properties pertinent to X-ray emission.

This work studies the relationship between laser irradiance and pulse frequency effect on plasma features of the TiO₂. This target was irradiated by a Q-switched nanosecond Nd: YAG laser with the first harmonic generation (FHG) wavelength (1064nm), laser energy 500mJ, and pulse frequency ranging from 6Hz to 10Hz at atmospheric pressure. The Boltzmann plot and the Stark broadening methods calculated the plasma parameters ($T_e$ and $n_e)$. The findings were examined in light of the previously published experiments and theories, and it was discovered that they agreed with the hypothesis of the local thermodynamic equilibrium (LTE); on the other hand, research was conducted on the other basic plasma properties such as the Debye length (${\lambda }_D$), the Debye sphere ($N_D$), and the plasma frequency (${\omega }_P$). We observed that all plasma parameters are influenced by pulse frequency. The results clarify the linear change in electron temperature at increasing pulse frequency for TiO₂ plasma. In contrast, the broadening of the line profiles related to electron density was evident with pulse frequency, causing an increase in electron density.

This research shows the optical emission spectroscopy (OES) of copper (Cu) plasma. Copper plasma was induced using a Q-switched Nd: YAG pulsed laser with the following parameters: fundamental wavelength (1064nm), energy range (400–600) mJ, frequency (6) Hz and laser pulses (10–30 pulses). Many characteristics of plasma, such as electron temperature ($T_e$), electron density ($n_e$), Debye length (${\lambda }_D$) and plasma frequency ($f_p$), have been determined via spectroscopic examination. Electron temperature ($T_e$) ranged from (1.47–1.759)eV, and electron number density ($n_e$) ranged from (6.3–11.4) $\times 10^{-17}$cm³. The picture of the site of laser bombardment of copper (Cu) metal displays three diameters or circles, each of which has a distinct hue. The laser’s interaction with the copper metal is seen via laser ablation, and the influence of the increasing energy of the laser is seen here during the spectroscopic diagnostic and the process of metal bombardment, leading to the formation of a crater.

This research paper presents the laser transformation hardening (LTH) to improve the surface hardness of commercially pure titanium, nearer to ASTM Grade3 chemical composition of 1.6mm thickness sheet using a CW (continuous wave) 2kW, with radiation wavelength $\lambda =1.06$$\mu$m Nd:YAG laser. Full factorial and response surface design approach in Design Expert 9 software have been discussed and evaluated by statistical regression analysis and analysis of variance. The experiment was carried out as the full factorial design (FFD) array of 27 with 3 factors, 3 levels, i.e. 3${}^3=27$ experiments. The selected input parameters are: laser power, scanning speed and focused position, and responses are: Vickers Microhardness on top surface, in fusion zone, and in heat affected zone. FFD and response surface methodology (RSM) were applied to evaluate and optimize the effects of laser process parameters on Vickers microhardness of laser hardened surface. The results show that, the hardness of as-received commercially pure titanium is approximately 153VHN and the hardness after laser transformation hardened bead geometrical surface is in the range of 200–240VHN. The hardness can be increased with the increase in the scanning speed and decrease in the optimum value of laser power i.e. heat input applied. It has been found that the quadratic model is best fitted for prediction of the Vickers microhardness of laser hardened surface. These findings are significant in modern development of hard surface coatings for corrosion and wear resistant applications. Application of experimental results will be considered in the aerospace, marine, chemical, medicine, automobile and the engineering industries.