Technology of pulsed laser surface coating in pressing tool repair

A pressing tool is a rarther complicated device operated in the conditions of loading of hundreds of tons, periodic temperature gradients of hundreds of degrees, and subject to the influence of corrosives. The paper describes the operation of restoring the geometry of the tool by pulsed laser surface coating with filler metal feed. Laser cladding is carried out on a process installation including a pulse solid-state laser on YAG: Nd with the emission wavelength of 1.06 μm. An algorithm of optimizing the design process is proposed. Using this technique makes it possible to significantly reduce the time of technological preparation of production, as well as the proportion of pilot studies. On the basis of the developed optimization techniques process parameters of laser cladding are selected. Macro- and micro- analysis of the surface under investigation is also carried out. Microhardness of the cross section of the basic material and surface coating is measured for the comparison and evaluation of their properties. The values of hardness (HRC) are chosen according to Rockwell hardness scale taking into account suitable ratios obtained according to Vickers (HV). Measurements of the material hardness are required to identify the ability to resist elastic and plastic deformation or fracture in the case of introducing a harder metal solid that does not take permanent set in the surface layer of the material.