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Both additive and hybrid manufacturing open many new possibilities and perspectives to manufacturing but until now the systems have been stand-alone technologies without real industrial implementation on workshop floor. The research is concentrated mainly in design and process optimization, and separate part printing. Therefore, automatic and flexible industrial production has not been possible with current technologies. Most of the process steps include manual work and development work is needed especially in pre- and post-processing of the AM machines. Some trials have been made e.g. on powder handling and part removal from system, but real solutions are not seen in markets yet. Also post-processes, i.e. stress relief and other post-heat treatments, as well as machining steps, grinding, polishing etc. need solutions. In addition quality inspection should be included in the total system. In the presentation the systems in the market are analyzed giving the possibilities for different and the current barriers hindering the controlled automatic production are presented to give perspective to the future work.

3D-tulostus eli lisäävä valmistus on viimeisten vuosien aikana tullut laajasti hyödynnettäväksi teknologiaksi erilaisissa teollisuuden ratkaisuissa. Samalla tietoisuus sen mahdollisuuksista on levinnyt laajasti myös PK-sektorille, joka on ottamassa teknologiaa lisääntyvästi käyttöön. 3D-tulostusta ei käytetä enää vain prototyyppien valmistamiseen vaan yhä enemmän suorassa tuotantokäytössä. Tämä on nostanut esiin uusia tarpeita ja kysymyksiä teknologioiden käytölle ja valmistettujen tuotteiden laadulle sekä standardisoidulle varmistukselle. DIMECCin MANU-ohjelman eräänä osa-alueena on ollut 3D-tulostuksen kehityksen tutkiminen ja sen mahdollisuuksien konkretisoiminen suomalaisen teollisuuden tarpeita vasten. Tämä opas on muodostunut MANUn tuloksena ja se tarjoaa käytännönläheisen käsikirjan 3D-tulostuksen hyödyntämiseksi teollisuudessa. Toivomme käsikirjan tukevan mahdollisimman monia 3D-tulostuksen hyödyntäjiä, aina vasta-alkajista kokeneisiin 3D-ammattilaisiin.

The optical attachment for transformation the spatial characteristics of excimer laser has been experimentally investigated. The laser beam of rectangular section with sizes of 3 x 20 mm and divergence of 2 x 5 mrad after passage of an optical attachment got the square form 20 x 20 mm and equal divergence of 5 x 5 mrad orthogonal directions. It is shown, that application of such unit in the facilities for microprocessing of materials simplifies an optical path of illumination module, allows to receive the optimum uniformity of irradiation (within 2 %) at reproductive image with micron accuracy in plane of processed material and to mitigate the beam load on optical elements due to suppression of influence of "hot" points.

This paper presents the current situation of laser processing technology in Finland; industrial activities, research, development and education. The Finnish laser processing R&D started in 1985 in Lappeenranta University of Technology.Major portion of industrial laser applications are laser cutting and laser welding has minor role. In the late 1990’s the number of laser welding applications started to grow and many subcontractors established facilities. Research and education on laser materials processing is concentrated in several universities, Lappeenranta and Tampere Universities of Technology, Aalto University and the research facility VTT Technical Research Centre of Finland Ltd. The main research fields are in laser and hybrid welding, surface treatment, laser welding of plastics, micro laser processing, paper processing and recently additive manufacturing. In addition, several Applied Universities and schools have started their education and service for the industry in laser and hybrid laser welding and cutting. The postgraduate educational activities in laser processing in Finland are comprehensive in all levels from laser operators to international laser experts.

Finnish laser materials processing activities started on 1982 by installing the first laser cutting system. In the start of research activities there were total 5 systems in Finland in 1985. Then a TEKES research programme "Laseriprojekti" (Laser project) was starting it. During three years many projects and systems were executed. On 90 s laser process revolution brought hundreds of cutting and marking systems to Finland and the activity was enlarged to many locations and organisations. The presentation tells how everything was started and what is the current status.

The Laser-GMA hybrid welding experiments are carried out for GMA-trailing hybrid welding in full penetration. High power fiber laser welding of 10 kW with 4 mm defocusing inside the work piece is used along with pulsed Gas Metal Arc Welding. Different concentration of Cr in base metal and filler wire are used to see the mixing behavior in Laser-GMA hybrid welding. Numerical simulations are carried out using the same power, defocusing, GMAW current and voltage pulse parameters and Cr concentrations as in experiments. The laser simulations used real time multiple reflection inside keyhole and continuity, momentum, energy conservation equations are solved using volume of Fluid (VOF) model. Simulation results for GMA-trailing configuration are presented for mixing and fluid flow behavior and it found that GMA-trailing configuration is giving comparatively uniform mixing and longer pool length is found at root surface. The results for simulation and experiments are compared. The results are in fair agreement in terms of upper bead shape but the molten metal is dropping down due to gravity in simulations, thus forming undercut which is not observed in experiments. This may be due to the fact that assist gas effect is not considered in simulations.

The transformation spatial characteristics of KrF excimer laser output beam was studied. It is shown that a rectangular 3×20mm laser beam with a divergence of 2 ×5 mrad acquired a shape of 20×20mm and a divergence of 5x5mrad after passing this unit.

The numerical simulations of high power laser keyhole welding at different welding positions are performed by using Volume-Of-Fluid (VOF) method. The main material is SS400. The multi-physics phenomenon is considered using several models, such as the heat flux of Gaussian heat source, the recoil pressure with Clausisus-Clapeyron equation, the Marangoni flow considering temperature gradient, the buoyancy force with Boussinesq approximation, the additional shear stress and heat source due to metallic vapor ejected through keyhole entrance, the bubble formation assumed as adiabatic bubble, and the multiple-reflection by solving proper discriminant, are used. To analyze the fluid flow pattern, the concept of streamline formed by reconstructing the value of the velocity vector is applied. Partial and full penetration cases at different welding positions are considered. The welding position seems to have only a minor influence on bead formation characteristics in both cases. This is probably due to the fact that the recoil pressure has a major influence when compared to other driving forces. The flow characteristics and fluid velocity in weld pool are analyzed to compare the gravity direction effect at different welding positions. It is observed that the clockwise flow pattern is mainly formed by the recoil pressure on the keyhole surface in the case of partial penetration. The laser energy can't maintain the whole weld pool when the weld pool size becomes too large. And then the solidification starts from the middle part of weld pool and a necked weld pool shape is formed. In the full penetration welding, the weld pool flow patterns are affected by the leakage of laser power through the full penetration keyhole and also by surface tension. Furthermore, the numerical simulation of full penetration welding with AISI316L is also performed to analyze the effect of material properties. The weld bead shapes obtained by simulations were compared with the corresponding experimental results to confirm the validity of the process models adopted and the CFD simulation tool.

Three dimensional numerical simulations are performed to analyze the fluid flow and mixing of alloying element in laser-gas metal arc (GMA) hybrid welding in full penetration welding with GMA leading configuration. Navier stoke's, continuity, energy and volume of fluid (VOF) equations are solved alogwith auxilary models for laser and GMA heat sources. Laser welding is considered using real time multiple reflection models using commerciallly avaialble flow software. The results are compared with experimentally obtained bead shape and the results are found to be in fair agreement. Two distinct flow patterns are found in upper and root surface of workpiece. The incoming metal mostly mixed in molten pool on upper surface therefore higher concentration of Cr is found in upper part of bead. Experimentally obtained EDS scans of Cr shows that mixing is higher in upper part of bead and this fact is also depicted in simulation but the amount of Cr of mixing would vary with location. Higher concentration is expected near the point of laser stoppage.

Influence of the laser beam intensity distribution spatial shaping on laser cutting was studied. Spatial shaping of CW fibre laser beam was done using liquid cooled liquid crystal on silicon spatial light modulator (Lcos-SLM). As result it was seen that even a simple shaping of intensity distribution of the Gaussian beam can enhance the cutting parameters.

Nickel screens and foams are commonly used in alkaline fuel cell (AFC) as substrates to support electrodes. The methods used for fabrication of these substrates impact significantly on the viability, with the material and processing cost of nickel comprising almost one third of the total. Therefore improvements to the manufacturing speed of substrates would increase affordability. Currently, state of the art commercial selective laser sintering (SLS) systems are limited to a volumetric manufacturing speed of 1-3 mm3/s. This study describes a novel technique that multiplies the sintering speed of nickel AFC substrates. The novel technique is based on an integrating mirror, which creates a homogenized 60 mm wide and 0.3 mm long beam from a Nd:YAG laser, and a 0.8 mm thick nickel powder layer in a nitrogen environment. The influence of the nickel powder characteristics, and sintering parameters, as velocity, laser power etc., and post-sintering treatments of the samples on the mechanical properties of the substrates were studied. Based on experimental results the sintering speed could be multiplied up to a factor of 150 compared to the standard laser sintering speed. Additionally, because structure of the substrate has a significant impact on cell performance, a case study was defined to present the performance and characteristics of the sintered substrates on AFCs. Laser sintered substrates show promise, exhibiting a small performance drop of less than 25 mV (about 7 %) compared to the in-house standard.