This work describes the influence of laser treatment on the structure and some properties of Al 2 O 3 , Al 2 O 3 + 5%Ni, Al 2 O 3 (95%Ni + 5%Al), Al 2 O 3 + 5%Ni - (95%Ni + 5%Al) and Al 2 O 3 + 5%Ni + CrAl layer oxide ceramic coatings of about 100 m thickness deposited by air plasma spraying on a heat-resistant alloy with a nickel matrix. It has been stated that laser remelting of power density 0.01-0.2 10 9 W m 2 and scanning rate within 5-7 m min 1 ensures good quality of ceramic coatings in comparison with not-remelted coatings. Laser treated ceramic coatings have a better thermal conductivity than as deposited layers. As shown by model calculations, after laser treatment, they show a smaller temperature drop over a given thickness. The erosion resistance of the coatings, however, is greater after laser treatment.

Abstract In this article, the effects of zero-point energy (ZPE) on the heat transport induced by ultra-short laser pulses are investigated. It is shown that the existence of the zero-point energy in a physical vacuum influences the heat transport on an atomic level. The interaction of the building blocks of matter-atoms with the zero-point fields (ZPFs), which generate the ZPE guarantees the stability of matter. The interaction of the ultra-short laser pulses ( t 1 as) with matter can be used as a source of information on the ZPF. Keywords: Ultra-short Laser PulsesQuantum Heat TransportZero-point EnergyZero-point Fields

This article presents a thermal finite volume model adapted to investigate laser processes. It is specially developed to treat moving heat sources with phase changes, melting and vapourisation. Heat transfer control in laser processing is particularly useful when processes must respect prescribed temperatures, or more generally, prescribed constraints. These processes involve generally several laser sources, or non-conventional power distribution. Hence, they have numerous parameters to set. Experimental optimisation is difficult and may be expansive. The numerical model is a useful and cheaper tool for development of those complex processes. For example in this article, two special laser processes are investigated: control of high carbon steel welded line cooling, zinc-coated sheets lap welding.