The director in charge of led flash light will host the meeting

The director of green laser pointer is in charge of the quality control of green laser pointer. It refers to the high-energy laser beam irradiation, the substrate surface with a thin layer of alloy elements added as needed while rapid melting, mixing, forming a thickness of 10 ~ l000 um layer of surface melting, solidification of molten layer to obtain the cooling rate of up to l05-108 ℃ / s, equivalent to quench hardening technology can achieve the cooling rate, and because the memory in a liquid melt layer diffusion and surface tension effects and other physical phenomena, so that surface only in the short report time (50us-2ms) with required depth and chemical composition of the surface alloying layer, non-equilibrium rapid melting process allows alloying elements in the organization after solidification had reached a high saturation, and thus form a common alloying method does not Rongyi the compounds, metastable phase and new phase, but also elements in the combined consumption of low Qian obtained under conditions of surface alloys with specific properties. Because of this alloy layer above the substrate of some performance, so we reached the table and modification purposes. The director in charge of green laser pointer is in the workshop.
Laser surface alloying process has been characterized only in the melting zone and the area had little impact on composition, structure and properties change, the thermal effect of the matrix can be reduced to a minimum, causing the deformation is minimal. It can satisfy the need to use the surface, without sacrificing the overall characteristics of the structure. As alloying elements are completely dissolved in the surface, the composition thus obtained is very uniform thin layer of cracking and spalling tendency is not so sensitive. The other notable feature is the use of laser power density is high (104-108 W/cm2). Melting depth by the laser power and exposure time to control, in the base metal surface to form a depth of 0.01 ~ 2mm of the alloy layer. As the cooling rate is high, so segregation is extremely small, and the grain refinement effect is remarkable. Laser alloying technique using cheap common materials can be useful for surface abrasion, corrosion, heat and other properties, from the surface can replace expensive overall alloy; and improved stainless steel, aluminum and titanium alloy wear resistance; Preparation of conventional metallurgical methods may not be some special materials, such as superconducting alloy, metal and glass. Surface hardening and ordinary arc and plasma spraying, laser alloying of the following advantages. The director in charge of led flash light will host the meeting.
Thin film can usually be pre-vapor deposition, vacuum sputtering, ion implantation by means of the system, and for the production of thick film presets. Can be used electroplating, spraying, rolling, diffusion (such as boronizing), pre-coated alloy powder or diaphragm and other methods. Rigid ion injection method is characterized by the same laser to melt the substrate surface while spraying people in the pool or hard alloy powder particles in order to achieve surface alloying. Laser gas alloying: refers to the appropriate atmosphere (nitrogen, carburizing atmosphere, etc.), the substrate using laser heating and melting the surface of the gas through the atmosphere, the reaction with the substrate, the thickness of the surface solid than those of normal processing to obtain the thickness of the reaction is much greater. It is mainly used in the A1, Ti and its alloys and other soft alloy substrate treatment, respectively, obtained TiN, TiC or Ti (C, N) compound layer such as surface hardness of up to l 000Hv more. Convection in the molten pool, the alloying elements can quickly penetrate the deeper parts. Laser surface alloying layer of tissue is characterized by alloying tissue heterogeneity. Includes three aspects: First, alloying heterogeneity within the pool, in its cross-section will be organized within the gradient; second alloy pool within the macro-organizational heterogeneity; third is covered in front of the large cyclical changes area alloying lap area. The workshop of green laser pointer is well organized.
Gradient in the organization, the common characteristics of complex organizations, there are three: flat crystal - crystal-like cells - cellular dendrite - dendrite; cellular crystal - cellular dendrite - dendrite; cellular dendrite - dendrite. Laser alloying of the macro-organizational heterogeneity is in some cases low magnification macro-organization of its non-uniform, which, from a physical metallurgy point of view, the formation of macroscopic tissue heterogeneity is mainly due to laser melting the alloy under not melt pool convection in the melt of the alloy elements within his mixing, the composition of the present macro-heterogeneity. Using laser surface alloying process can be in some cheap, poor surface properties of the system out of the base metal surface wear and corrosion, high temperature alloy surface, the overall alloy to replace expensive, saving precious materials and strategic materials, the Authority, the low-cost alloy for more widely used, thus greatly reducing costs. In addition, it can also be used to create a performance with the conventional metallurgical methods fundamentally different surface alloy, for example, foreign laser surface alloying process developed superconducting alloy MoN, MoC and V3Si, the surface of the metal used to make glass FeCrCB, NiNB and so on. The workshop of green laser pointer is under construction.