The bonding and crystalline structures of oil-fried fly ash collected from a power plant were analyzed by using Raman spectroscopy and X-ray diffraction (XRD), respectively. These carbon powders underwent a series of annealing treatment for graphitization and crystallization. In Raman spectra, the refined, unburned carbon contains clearly the D, G and D peaks under 2000 or 2700 • C treatment. The Raman spectral line shape of refined, unburned carbon heated at 2700 • C is similar to that of commercial graphite made from graphitization process. In the XRD spectra, the refined, unburned carbon contains (002), (100) and (004) diffraction peaks under heating at 2000 or 2700 • C. The XRD spectral line shape of refined, unburned carbon heated at 2700 • C is similar to that of a commercial graphite bar. The quantitative graphitization level from Raman spectra and crystallization degree from XRD spectra on refined, unburned carbon powders serve as preliminary guide for the qualitative evaluation of these unburned carbon powders.

Laser protection for optical components, particularly those in high-power laser systems, has been a major concern. LaSrTiO with its good optical and thermal properties can be potentially applied as a high-temperature optical protective coating or high-reflectivity material for optical components. However, the high-power laser ablation behavior of plasma-sprayed LaSrTiO (x = 0.1) coatings has rarely been investigated. Thus, in this study, laser irradiation experiments were performed to study the effect of high-intensity continuous laser on the ablation behavior of the LaSrTiO coating. The results show that the LaSrTiO coating undergoes three ablation stages during laser irradiation: coating oxidation, formation and growth of new structures (columnar and dendritic crystals), and mechanical failure. A finite-element simulation was also conducted to explore the mechanism of the ablation damage to the LaSrTiO coating and provided a good understanding of the ablation behavior. The apparent ablation characteristics are attributed to the different temperature gradients determined by the reflectivity and thermal diffusivity of the LaSrTiO coating material, which are critical factors for improving the antilaser ablation property. Now, the stainless steel substrate deposited by it can effectively work as a protective shield layer against ablation by laser irradiation.

Based on the invariable stretching stress preloading device, the experimental investigation on damage effect of 30CrMnSiA steel structure specimen by continuous laser was carried out. While the stress is between 660MPa and 1140MPa, the average laser power density is between 110W/cm 2 and 330W/cm 2 , we can get the conclusions as follow:(1) When the preloaded stretching stress increases, the necking phenomenon becomes unobvious. (2) When the preloaded stretching stress increases, both the rupture time and rupture temperature decrease monotonously. (3) When the laser power density increases, the rupture time decreases monotonously. (4) When the preloaded stretching stress or laser power density increases, the rupture threshold decreases monotonously. (5) The strain of the specimen before necking is small, and the specimen metamorphoses during necking period and the deformation of specimen is centralized in the necking region.

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