The main purpose of this project was to study and improve the tribological characteristics of hip and knee prostheses in order to use them for a longer period of time. We conducted a thorough investigation of components of hip and knee prostheses. We started with the study of hip prostheses obtained after revision surgery. In this paper we present some experimental results about the scratch resistance of Ti6Al4V alloy and Co-Cr alloy femoral heads coated by physical vapor deposition (PVD) with TiN and Co-Cr-Mo, respectively. Visual analysis and optical microscopy analysis of prosthetic components revealed numerous multi-directional scratches, deeper or less deep, frosted the surface in the geometric place of action of the resultant force application point, microcorossion and peeling of the coating on the prosthetic femoral heads made of CoCr coated with CoCrMo by PVD method. Scratches, corrosion, peeling and bio-tribo-corrosion of titanium nitride (TiN) coating from the Ti6Al4V femoral heads surface were also observed. Using atomic force microscopy (AFM), topographic characterization at nanometric scale of these surfaces was realized. Surface topography parameters such as minimum and maximum height, average roughness, and surface asymmetry were derived. It resulted that under the deposition there is a more veiled area. Roughness was used as an indicator of damage to the femoral head to obtain information on the variation in height from one point to another. AFM analysis revealed a dramatic increase in average roughness (Ra) of femoral heads compared to the maximum value of 0.05 μm provided under ISO 7206-2. From all these studies it was noted the need for a resistant prostheses, with anticorrosive composition and high mechanical properties. Among the numerous methods to reduce wear we realized thin films (biocompatible nanomaterials) deposition of TiN on 316L SS steel substrates by pulsed laser deposition method (PLD), to improve overall performance and, in particular, mechanical prosthesis of hip prostheses structures. The results obtained leads to the conclusion that PLD technique is a good method to make amorphous and crystalline films, dense and porous by controlling the laser system conditions. All parameters can be controlled and varied to identify the optimum structures and to obtain thin layers.

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Additive Manufacturing (AM) concerns all classes of materials – polymers, metals, ceramics and glasses as well. For this reason, AM is in the focus of material scientists from all branches. Leaders of the industry realize that the possibilities of 3D printing are endless, and that these possibilities need ways and means to be taken full advantage of. Today, aerospace engineers are using the fused deposition modeling (FDM) method for rapid prototyping, part manufacturing, and tooling. They are followed by leaders and engineers from industry (industrial machines, motor vehicles, consumer products, medical/dental) but also from academic institutions and government/military.

The main objectives of the present project are to study and to improve mechanical properties of different systems from mechatronic and biomedical domains, in order to increase their functionality and life span. This is why nanostructured thin films (e.g. Al, Cr, Ti, Ti/Al multilayers) were deposited on different steel substrates, used in mechatronic and biomedical applications. By the characterization of coated surfaces of the products used in various fields such as medicine, mechatronics, electronics, etc. depends their proper operation, durability and reliability. This is the main reason why, we studied new types of layers and multilayers using Atomic Force Microscopy and scratch tests. The main result of the realized tests is that all studied nanostructured thin films offer the possibility of increasing the lifetime of substrates, being an important factor for proper functional operation, durability and reliability of the final systems in which they are used.

The newly invented word << ADAPTRONICS >> describes essentially technical and technological fields internationally known as intelligent systems, smart structures and smart materials, smart processes, describes how easy is it to build adaptive systems and structures, with the objective of reduction of material, technological and energy for implementation and operation to an absolute minimum, describes different scenarios for such applications focused on trying to simulate "vital functions", and the ability of biological systems to recognize and automatically correct the dysfunctions of their their structure, characteristic desired in technical systems and structures, particularly in areas where safety is essential (eg aircraft, civil structures, etc.), describes "scientific pillars" of the disciplines involved and important components of future structures and systems etc.