The present paper presents the results of the analysis made on samples obtained by additive manufacturing processes, necessary to realize prostheses and medical instruments. The samples were obtained by melting fine metal powder of Co-Cr by rapid prototyping process -Direct Metal Laser Sintering (DMLS). The examination of the samples (by methods of optical microscopic, scanning electron microscopy (SEM) and the spectroscopy method of X-ray energy dispersion) revealed that the surface of the obtained components contains incomplete melting areas whose size depends on the shape of the surface and the meshing level of the 3D model.

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The present paper proves the feasibility of a semi-automatic control system of high frequency ultrasound for welded plastic pipes, by ultrasonic methods. The paper presents the main existing types of plastic materials, the technological joining possibilities, the problems that may occur in welding and control and the reasoning of the chosen examination method. The theoretical size of the reference ultrasonic parameters for the propagation of ultrasounds through the flawless juncture. The samples were welded using electro fusion (EF) under different working conditions. The samples were assessed circumferentially, every 10 degrees, on different working frequencies. A semi-automatic control system was designed and developed. For the optimal working frequency, a set of 10 measurements was done, in similar working conditions, on the automatic control stand, in order to test the systems’ capability and the results’ repeatability. The measured values were compared with the limits considered to be admissible using Shewhart statistic control charts.

Recipient type products from energetic and chemical industry undergo a wide combined process of corrosion and ware, due to working environment. In order to put this products back in use, in a shorter period of time, welding reconditioning procedures are applied which mainly aim to restore the geometrical configuration but also the characteristics growth. Any welding technology applied, involves melting a filler material but also a part of the base material, mixing them, thereby obtaining the welded joint. The paper present the experimental results obtained in determining the optimal parameters for Metal Active Gas welding deposit that are going to be used for the restoration of some components from energetic and chemical industry and that are highlighting the dependence between the deposit parameters and the chemical composition of the juncture.

All vessel-type products operating under extreme conditions of temperature, pressure and corrosive environments, such as those in the power, chemical and petrochemical industries, are subjected to intense chemical / structural degradation processes that may lead to cracks. These may propagate in time, causing the product to fail, generating significant economic and material consequences, leading in some cases even to the loss of human lives. The paper presents some effects of the sacrifice layer repairing technique used to restore the geometrical shape by welding of the area from where the flaw material was removed, on the chemical composition.