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One of the major challenges for laser hardening is dealing with the geometrical singularities of the treated components. The problem arises from the laser hardening of uneven surfaces such as those with sharp edges or holes. In these cases, due to the differences in the surrounding volume of the material, overheating problems often appear leading to unacceptable treatment results. Despite several works tackling the problem of achieving uniform transformation profiles, the problem of the design and control of a beam delivery strategy leading to a desired transformation profile in the general case is considered to remain a true technical challenge. The main goal of this work is to present the control software developed by Talens Systems, which allows a customized laser beam delivery, providing different energy density patterns. By modifying these patterns in real time by means of scanning optics, the beam shape is able to adapt to almost any part geometry with full control of energy density, avoiding undesirable overheating effects. In addition, thanks to the modulation of the laser power and the changing speed of the scanning mirrors, the ability to “dodge” certain areas is possible and presents itself as one of the most interesting skills from the dynamic optical system shown in the present work. As an example of the success of this technology, automotive pieces have already been satisfactorily heat treated, meeting specific depth and hardness requirements. The developed knowledge and methodology could find applications in other laser processes such as cladding, welding, remelting, and alloying.

Nickel–aluminum bronze was subjected to laser heating to change the microstructure on the surface for enhanced corrosion performance. To develop the laser processing parameters, a two-phase diffusion model was used to determine the phase transformation kinetics. Also, an analytical laser heating model was employed to determine the laser power setting required to process just below the melting point. The result was that the lamellar κIII phase of the as-cast microstructure was dissolved up to 1.3 mm deep. Electrochemical testing revealed an increase in the corrosion potential and hence improved corrosion resistance for the laser processed surface, supporting the use of this process for enhanced corrosion performance of nickel–aluminum bronze components.

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