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The biomaterials most widely used for hard tissue implants (in orthopaedics, dental implants, and skull bones) are Ti-based biomaterials and Ti coated with hydroxiapatite (HAP). Because metallic biomaterials have some disadvantages as reported previously (mainly due to the difference between the mechanical characteristics of the human bone and the metallic implant), biocomposites have become an interesting solution to improve the hard tissue implants for the human body. This article presents the experimental results concerning the processing of HAP/Ti biocomposites by powder metallurgy technology. The initial powder mixture consists of HAP powder particles (<200 nm) reinforced with 100 μm titanium particles in the ratio 3:1 (wt%). Two different sintering routes are used: spark plasma sintering (SPS) at (1000-1100) • C for 10 or 20 min and two-step sintering (TSS) with the first step at 900 • C/1 min, followed by the second step at 800 • C for 300, 600, 900 or 1200 min. The ball-on-disc dry wear tests are developed using, as a moving counterpiece, DIN 100Cr6 tool steel balls (6 mm diameter; Ra < 3.2 μm; HRc 60-64; density >7.6 g/cm 3 ). The tribological behaviour of the processed biocomposites is appreciated on the basis of the coefficient of friction and wear rate, corroborated with the wear track depth. The final remarks of this article underline the potential use of SPS technology to obtain HAP/Ti biocomposites with comparable wear properties as similar materials processed by more complex technologies. Also, TSS allows processing HAP/Ti materials comparable with the SPS-ed ones from the point of view of the wear behaviour, except for the dwell time of the second step, which is critical for the wear behaviour.

Analysis of failure modes and effects (FMEA) is a method of analyzing the potential failure of a product or process, to develop an action plan aimed at their prevention and increased quality of products, processes and job production environments. As a method of critical analysis, FMEA has very clear objectives aimed at: determination of the weaknesses of a technical system; initiating causes of failure-seeking components; analysis environmental impacts, safety of operation, the product value; provision of corrective actions to remove the causes of the occurrence of defects; provision of a plan to improve product quality and maintenance; determining the needs of technology and modernization of production; increasing the level of communication between departments working people hierarchical levels. FMEA should be used before taking the product. There is no point subsequently, only because customer demands, to achieve FMEA. Therefore, FMEA must be within organizational conduct. Using timely analysis FMEA - Process avoid costly modifications of the technological achievement assembly "stator Housing" by identifying potential defects, avoidance and risk and potential consequences of faults. We studied the potential causes of defects and have proposed improvements. Among these are: implementing and tracking preventive maintenance program; providing specific compliance welding; acquisition of a specialized table seating and download the blank; purchasing a scarfing machine.

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In the railway sector, on the prototyping phase of product made by composite materials, it is necessary the implementation of a strict quality control using the instrument First Article Inpection (FAI). In this paper some of the most important steps in quality control implementation of FAI for composite parts at the prototyping parts made of composite materials in the railway field are presented. Thus, the necessary steps for developing FAI and the process diagram are given. Also, the method FMEA process is presented in order to eliminate the risks of errors and defects during the development of the technological process for obtaining the composite piece.