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By using SMAs formulations based on Cu-Zn-Al, the electrical resistivity by employment of an Agilent 4294A Precision Impedance Analyzer was analysed. It results that the different percentages of the metals which make up an SMA, do have an important influence upon resistivity. In particular, for one of the analyzed samples, it was observed that the SME was manifested as a form of “electric properties” memory. The experimental data was fitted using both Gaussian and polynomial fitting.

Shape memory alloys (SMA in short) exhibit a series of properties which are very different compared to regular metallic materials. One of their main characteristic is the ability to change their geometric shape when subjected to an increase from a low to a high temperature. In certain conditions, this shape change can be reversible, such that the material can “memorize” two geometric shapes: the high temperature shape (the “warm” shape) and the low temperature shape (the “cold” shape). These transformations occur due to an effect known as shape memory effect (SME in short). Moreover, through SME, the material is able to produce mechanical work when shifting from the “cold” shape to the “warm” one [1]. The discovery of these alloys is linked to the highlighting of a specific property which actually pertains to only several of said alloys (being uncommon for a metallic material) and which is known as “rubber-type behavior”. Many types of SMAs are very expensive, due to their composition (which includes noble metals) and their complex manufacturing technologies.. The most commonly encountered alloys nowadays are Ni-Ti, Cu-Al-Zn and Cu-Al-Ni which are employed in a plethora of practical applications.

By assimilating shape memory alloys with mathematical multifractal-type objects, a theoretical model based on Scale Relativity Theory in the form of The Multifractal Theory of Motion, in order to explain the mechanical behavior of such material, is proposed. The model is validated by analyzing the mechanical behavior of Cu–Al–Zn shape memory alloy with various chemical compositions. More precisely, the multifractal tunnel effect can “mime” the mechanical hysteresis of such a material, a situation in which a direct correspondence for several mechanical properties of Cu–Al–Zn is highlighted (the chemical composition can be correlated with the shapes of the curves controlled through the multifractality degree, while the areas delimited by the same curves can be correlated with the multifractal specific potential, as a measure of the mechanical memory degree).

Crystalline CuCexFe2-xO4 nanoparticles with different rare earth metal content (x = 0.00, 0.03, 0.05, 0.08 and 0.10) were synthesized using a co-precipitation technique that involves a 600 °C calcination treatment. The newly obtained powders were pressed into pellets and heated up to 950 °C in order to form a compact and less porous material, ideal for dielectric measurements. X-ray investigations revealed a structural modification from typical cubic system to a tetrahedral spinel form, accompanied by Ce3+ cations exclusion and formation of secondary phases. The amount of phases and cations distribution were determined by Rietveld refinement method. A degradation process of cerium doped copper ferrite was proposed based on X-ray analysis and Rietveld refinement. Furthermore, the magnetic behavior of both 600 °C and 950 °C samples was investigated from the hysteresis loops recorded from a vibrating sample magnetometer (VSM) in a ±10 kOe range. Room temperature dielectric values for the 950 °C samples were determined using the parallel-plate capacitor configuration in a frequency range of 10 Hz – 1 MHz.

Beside metallic biomaterials there is increasing interest in using degradable materials in a high number of applications. Zinc-based materials are a solution for biodegradable applications based on their mechanical and chemical properties. The experimental alloy ZnMg-Ca was obtained in an air-controlled atmosphere furnace after five re-melting operations. The material was in vitro analyzed from a corrosion resistance point of view. The experiments were realized by linear polarization (LP) and cyclic polarization (CP). Material surfaces before and after corrosion tests were analyzed through scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX).

A commercial Fe-C material (P265GH) used for natural gas delivery and transportation systems was analyzed in H2S atmosphere in order to establish the corrosion resistance. In most of the industrial processes for gas purification the corrosion rate is speed up by the presence of sulphur (S) especially as ions (HS-, SO32−) or different species like H2S. The H2S (hydrogen sulphide) is, beside a very toxic compound, a very active element in the acceleration of metallic materials deterioration. For experiments we used a three electrodes cell with Na2SO4 + Na2S solution at pH 3 for two different temperatures, room temperature ∼ 25 °C (sample 1) and at 60 (sample 2) ±1 °C in order to realize EIS (electrochemical impedance spectroscopy) and potentiodynamic polarization. After electro-chemical tests and corrosion resistance characterisation the material surface was analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS).

High damping capacity materials present an increased interest in many applications were vibration and noise reduction is absolutely necessary. Metallic materials with a high internal friction (IF) are becoming valuable because of them usual mechanical properties that fulfill the damping capacity in applications. Some of the shape memory alloys present a huge damping capacity during the solid state transformation (M↔A) based on the re-orientation and accommodation of the material structure. Iron based shape memory alloy present the best advantages for industrial application as dumpers in different areas. Beside civil construction domain these materials can cover also applications in automotive industry as shock impact absorbers for low velocities as protection for engine parts and also for noise reduction. By these means in this article we analyze FeMnSi+Al alloy with a new chemical composition obtained through classical melting method in Ar controlled atmosphere.

Biodegradable metallic materials gain space in implantable materials field based on the applications that can fulfill. Beside Mg-based alloys a new class of metallic materials is under development, alloys based on Fe, in order to improve the corrosion rate, one of the disadvantages of magnesium alloys, and the mechanical properties of the implant. In this article we present the steps took to obtain a biodegradable FeMnSi alloy with metallic additions and few preliminary results about the chemical composition (X-ray dispersive energy analyze EDS) of the sample and the influence of hardening heat treatment on chemical composition. After the melting and pouring stages the new material was analyzed.

New requests from the automotive industry suppose to apply new materials with mechanical resistance to heat and vibrations and also with low weight. In order to replace plastic materials with high damping capacity a viable solution can be the metallic materials with sufficient internal friction to transform the external mechanical energy in thermal energy without affecting the microstructure or the mechanical properties of the metallic materials. In automotive applications an important role, especially in low velocity impacts, are the bumper elements. In this article possibility of copper-based shape memory alloys to fulfill the damping necessity of metallic materials is analyzed. Dynamic - mechanical analyze of few copper based shape memory alloys is realized and the results compared to proposed a better solution of Cu-based shape memory alloy for damping materials applications. The damping capacity difference between martensite and austenite like phases is also analyzed.

In vitro electrochemical characterization and in vivo implantation in an animal model were employed to evaluate the degradation behavior and the biological activity of FeMnSi and FeMnSiCa alloys obtained using UltraCast (Ar atmosphere) melting. Electrochemical characterization was based on open circuit potential measurement, electrochemical impedance spectroscopy and potentiodynamic polarization techniques while the alloys were immersed in Ringer’s solution at 37 ºC for 7 days. Higher corrosion rates were measured for the Ca-containing material, resulting from inefficient passivation of the metal surface by oxy-hydroxide products. In vivo osseointegration was investigated on a tibia implant model in rabbits by referring to a standard control (AISI 316L) stainless steel using standard biochemical, histological and radiological methods of investigation. Changes in the biochemical parameters were related to the main stages of the bone fracture repair, whereas implantation of the alloys in rabbit’s tibia provided the necessary mechanical support to the injured bone area and facilitated the growth of the newly connective tissue, as well as osteoid formation and mineralization, as revealed by computed tomography reconstructed images and validated by the bone morphometric indices. The present study highlighted that the FeMnSiCa alloy promotes better osteoinduction and osseointegration processes when compared to the base FeMnSi alloy or with AISI 316L, and in vivo degradation rates correlate well with corrosion resistance measurements in Ringer’s solution.

A biodegradable iron based alloy was obtained through classical melting method using a furnace with controlled atmosphere. The metallic material was obtained from high purity materials using a proper obtaining method. The material is proposed as an alternative to magnesium alloys that have a very fast degradation period for applications with longer healing periods (more than 3 and between 12 to 18 months). The material was analyzed using scanning electron microscopy (SEM) and X-ray dispersive energy analyze EDAX, before and after implantation to observe the influence of the human medium on the metallic implant. Both implantation areas (subcutaneous and in bone) indicate reactions with the biological environment as compounds form on the surface or with loss of metallic material. Bio-chemistry of Ca, P and Mg of the implanted subjects was realized for subcutaneous and in bone implantation comparing with the results of a Zr implant behavior. In vivo experiment on Wistar rats highlight a very good bio-compatibility of the subcutaneous implant by the absence of any kind of local reaction or toxic systemic fact, which is explained by slow degradation of FeMnSi alloy and the metabolism of resulted products in conditions of maintaining organism homeostasis.

Bumper beam absorbs the accidental kinetic energy by deflection in low-speed impact and by deformation in high-speed impact. Based on the last years necessity of lighter materials and safer usage of vehicles we try to come with a new class of materials for bumper systems. Analyze of metallic materials is cheaper when the analyze take place on a computer avoiding the metallic loss or energy consume. We present few results obtained in Catia software about the behavior of some metallic materials under external solicitations in function of the mechanical properties of metallic elements, geometry of the element, restrains and solicitation points. Shape memory alloy are smart materials that can use the external mechanical energy damping to thermal energy in bumper applications. In martensite to austenite domain we observe an increase of damping mechanical capacity with possible applications in bumper systems.

A new FeMnSi metallic alloy is proposed as biodegradable material with applications in medical field. The corrosion behavior in simulated body fluids is evaluated after immersion for 14 days. The metallic biodegradable material surface was analyzed with a SEM (2 and 3D)+EDAX equipment. The effects of the solution on the metallic surface present an area with pitting corrosions, marks around 10 µm in depth, and a different one with new chemical compounds form from biological solution with good stability on the surface. Even if is a new biodegradable material based on iron simmilar results about the surface behavior were obtain by other researchers on different FeMnSi chemical compositions.

Magnesium based alloys, especially Mg–Ca alloys, are biocompatible substrates with mechanical properties similar to those of bones. The biodegradable alloys of Mg–Ca provide sufficient mechanical strength in load carrying applications as opposed to biopolymers and also they avoid stress shielding and secondary surgery inherent with permanent metallic implant materials. The main issue facing a biodegradable Mg–Ca alloy is the fast degradation in the aggressive physiological environment of the body. The alloy's corrosion is proportional with the dissolution of the Mg in the body: the reaction with the water generates magnesium hydroxide and hydrogen. The accelerated corrosion will lead to early loss of the alloy's mechanical integrity. The degradation rate of an alloy can be improved mainly through tailoring the composition and by carrying out surface treatments. This research focuses on the ability to adjust degradation rate of Mg–Ca alloys by an original method and studies the biological activity of the resulted specimens. A new Mg–Ca alloy, with a Si gradient concentration from the surface to the interior of the material, was obtained. The surface morphology was investigated using scanning electron microscopy (VegaTescan LMH II, SE detector, 30 kV), X-ray diffraction (X’Pert equipment) and energy dispersive X-ray (Bruker EDS equipment). In vivo degradation behavior, biological compatibility and activity of Mg–Ca alloys with/without Si gradient concentration were studied with an implant model (subcutaneous and bony) in rats. The organism response to implants was characterized by using radiological (plain X-rays and computed tomography), biochemical and histological methods of investigation. The results sustained that Si gradient concentration can be used to control the rate of degradation of the Mg–Ca alloys for enhancing their biologic activity in order to facilitate bone tissue repair.

Designing substrates having suitable mechanical properties and targeted degradation behavior is the key's development of bio-materials for medical application. In orthopedics, graft material may be used to fill bony defects or to promote bone formation in osseous defects created by trauma or surgical intervention. Incorporation of Si may increase the bioactivity of implant locally, both by enhancing interactions at the graft–host interface and by having a potential endocrine like effect on osteoblasts. A Fe–Mn–Si alloy was obtained as alloplastic graft materials for bone implants that need long recovery time period. The surface morphology of the resulted specimens was investigated using scanning electrons microscopy (VegaTescan LMH II, SE detector, 30 kV), X-ray diffractions (X’Pert equipment) or X-ray dispersive energy analyze (Bruker EDS equipment). This study objective was to evaluate in vivo the mechanisms of degradation and the effects of its implantation over the main metabolic organs. Biochemical, histological, plain X radiography and computed tomography investigations showed good compatibility of the subcutaneous implants in the rat organism. The implantation of the Fe–Mn–Si alloy, in critical size bone (tibiae) defect rat model, did not induced adverse biological reactions and provided temporary mechanical support to the affected bone area. The biodegradation products were hydroxides layers which adhered to the substrate surface. Fe–Mn–Si alloy assured the mechanical integrity in rat tibiae defects during bone regeneration.

Biodegradable materials are considered to be the third generation of biomaterials. The aim of these biodegradable alloys is to provide healing and tissue regeneration of the bone. In recent years new types of BM, such as Mg-Si-Ca based alloys were developed and are considered promising candidates for implant materials during a limited time. The effect of Si and Ca addition on pure magnesium alloy has been investigated. The results showed the formation of an intermetallic compound Mg2Si. Morphology of this compound changed to polyhedral shape with increasing Si addition over 3wt%. The purpose of this paper is to investigate morphological and XRD aspects of casted pure Mg and Mg-XSi-YCa (X – 1.5wt%, 5wt%, 10wt% / Y-0.5wt%, 1wt%, 2wt%) by using optical microscopy, scanning electron microscopy and X-ray diffraction.

In this study, nano-silicon (Si) thin films were deposited on biodegradable Fe–1.5Mn–1Si substrate by pulsed laser deposition (PLD) method. Biodegradable metallic materials represent a good solution in implantology field based on the elimination of the second surgical operation required for the extraction of the material. Also, using biodegradable materials medical complications between the metallic implant and the human body that might appear during the recovery period are excluded. In this sense we propose a metallic material based on iron with a longer degradation period compared to Mg-Ca based materials. Scanning electron microscopy (SEM) and X-ray dispersive energy analyze (EDAX) were use to analyze the implant material surface before and after Si thin film deposition and before and after implantation.

Entire or partial loss of function in the shoulder, elbow or wrist represent an increasingly common ailment connected to a wide range of injuries or other conditions including sports, occupational, spinal cord injuries or strokes. A general treatment of these problems relies on physiotherapy procedures. An increasing number of metallic materials are continuously being developed to expect the requirements for different engineering applications including biomedical field. Few constructive models that can involve intelligent materials are analyzed to establish the advantages in usage of shape memory elements mechanical implementation. The shape memory effect, superelasticity and damping capacity are unique characteristics at metallic alloys which demand careful consideration in both design and manufacturing processes. The actual rehabilitation systems can be improved using smart elements in motorized equipments like robotic systems. Shape memory alloys, especially NiTi (nitinol), represent a very good alternative for actuation in equipments with moving dispositive based on very good actuation properties, low mass, small size, safety and user friendliness. In this article the actuation and the force characteristics were analyzed to investigate a relationship between the bending angle and the actuation real value.

There is the opinion, imprinted by tradition, that only bronze alloyed with tin may be used to build bells, musical instruments or sound transmitters, without the need to bring a scientific explanation. Starting from the physical theory and experimental determination that sound travels only through bodies with elastic proprieties, a study over acoustic white cast iron was proposed. After convincing experiments, it results that white cast irons have good properties for producing and transmitting sound waves. The measurements focused two fundamental aspects, the elastic energy available for producing and transmitting sounds and amortization, resulting that white cast irons can substitute with success bronze with tin or even better properties.

The paper is a practical study, in which the authors have proposed to improve the reliability in operation of hot work tool steels, used for the manufacturing of seamless steel tubes.There were developed samples of hot work tool steel with different chemical compositions by micro-alloying with Mo. The samples were studied in order to investigate their structure and the relations between the microstructure and in-situ behavior.

Implants based on titanium alloys, stainless steel and cobalt –chromium have been the primary biomaterials used for load bearing applications and they have been remarkably successful throughout time, but on the long term, there appear a series of inconveniences regarding these metallic implants. Thus, there have been cases of aseptic osteolysis around the implant, with pain and high degree of loosening of the prosthesis which constitutes a limitation of the long term benefits of metallic implants. Therefore, researchers have found new materials for implants, more competitive and efficient. These are materials that are biocompatible and biodegradable. These constitute a novel class of bioactive biomaterials which are expected to support the healing process of a diseased tissue and to degrade thereafter. Magnesium alloys attracted great attention as a new kind of degradable biomaterial. Mg is an essential mineral for human metabolism and its deficiency has been linked to various pathological conditions. The main advantages of Mg alloys are its superior mechanical and biocorrosive properties and its biocompatibility. Mg is a very light-weight metal with a lower density than that of biocompatible Ti alloys, which is closer to that of the human bone. In the present paper we shall focus on presenting some biological testing studies of several Mg alloys from the system Mg-Ca, with different percentages of Ca. Three methods have been use for this: determining the ph at different sample incubation times in culture environment; citotoxicity tests made in vitro which: evaluate the contact toxicity by putting the samples in the buckets of cellular culture plates; evaluate the cellular proliferation at the surface of the tested materials by fluorescence microscopy and deflection microscopy; evaluation of toxicity by testing the effect of the extraction liquid resulting from the incubation of the material with testing cell specific culture environment.

Equi-qtomic NiTi (nitinol) shape memory alloy (SMA) is a good potential candidate material for use as thermo-mechanical actuator in a large variety of engineering like automotive and aerospace applications. Shape memory alloy in action are required to perform a large number of actuation cycles under cyclic thermo-mechanical loads and therefor are subject of fatigue. A shape memory alloy, supplied from Nimesis Technology, with martensite to austenite temperature transformation domain 76-80 °C. The material characteristics were investigated through differential calorimetry (DSC) before and after the thermo-mechanical solicitations. Under Joule effect and a timer, the active element goes up to 3000 cycles with a 500g weight on. The properties of thermo-elastic martensite transformation are the elastic accommodation of volume and shape change that takes place due to change in crystal structure upon phase transformation. A modification of the first coil of the intelligent arch-wire suffer a modification of the temperature transformation domain increasing the As and Af temperature values.

This paper represents a comparative study of several biodegradable alloys based on Mg, and respectively Mg-Ca and Mg-Ca-Si. The way these alloys were obtained and their comparative analysis are presented by means of results to the cytotoxicity tests, considering the biocompatibility and the degree of biodegradation of the studied alloys. Their production was undertaken in extreme lab conditions, in controlled atmosphere, in order to obtain precise compositions. Thus, we produced alloys from the Mg-Ca system, with the following Ca concentrations: 0.82%Ca, 0.84%Ca, 0.85%Ca, and for the Mg-Si-Ca system, we produced the alloy with Ca and Si in 0.4% concentration. For the cytotoxicity tests, undertaken within the Cellular Biology laboratory of the University of Medicine and Pharmacy Gr. T. Popa Iasi, we used a standard DMEM (Dulbeko Modified Eagle Medium) culture environment with 10% addition of fetal bovine serum and 4.5g/l glucose.

Shape memory alloys represent a perfect solution for noiselessly actuation with possibility of natural activation without extra energy consume. Copper-based shape memory alloy represent a cheap solution of classical Nitinol. After melting and heat treatment the experimental alloy was mechanically polished and chemical etched in order to highlight the alloy microstructure in hardened state. In this article results about an experimental alloy microstructure relief are presented. Scanning electron microscopy (SEM, VegaTC demo) and atomic force microscopy (AFM, Nanosurf EasyScan II) were used to analyze the profile of a shape memory alloy based on copper after the annealing heat treatment.

Besides biocompatible materials, a new class of metallic materials with medical applications dedicated to specific traumas is that of biodegradable materials. Zinc-based materials are mentioned as the ‘Calcium of the XXI century’. Zn has been considered as one of the newest promising biodegradable metallic metals together with Mg-based and Fe-based alloys. A new experimental composition of ZnMgCa alloy was obtained using an induction furnace from high purity zinc, magnesium and calcium materials. The material chemical compounds and phases were determined using EDS Bruker detector and XRD X’Pert equipment in molded state of the alloy. Microstructure of the alloy was determined using scanning electron microscopy and the distribution of constituents using VegaTescan software.

Copper-based shape memory alloy (SMA) was obtained through a classic melting method. The material was analyzed in heat treated and deformed states using scanning electrons microscopy (SEM), dilatometry (DIL), differential scanning calorimetry (DSC), dynamic mechanical analyzer (DMA) and energy dispersive X-ray analyze (EDAX) to establish the material microstructure, memory properties like martensitic transformation domain and rate or damping capacity. The material exhibits a good shape memory effect and high internal friction and it is proposed as target in a pulsed laser deposition (PLD) process for obtaining thin films. The deposition process is described in this paper through presented experimental results on the layer.

The high reversibility of the martensitic transformation occurring in shape-memory alloys (SMAs) is at the origin of the mechanical performance of these materials. Infrared thermography is employed in this study to measure the mechanical dissipation produced by Cu–Zn–Al SMA specimens during stress-induced phase transformation. In practice, temperature change is first measured on the surface of a specimen subjected to cyclic mechanical loading at constant ambient temperature. The heat produced by the material can then be deduced from the temperature change by using the heat diffusion equation. The heat associated to mechanical irreversibility is expected to be very low compared to the other heat quantities produced by the material (such as the latent heat due to phase change and the heat due to thermoelastic coupling), so measuring this quantity requires special attention, as emphasized in this paper. The procedure which enables us to extract the mechanical dissipation from the measured heat source is first presented. The technique is then applied to two types of specimens: martensitic and austenitic. Different values of mechanical dissipation were measured, thus revealing different levels of mechanical irreversibility.

FeMnSi alloys are promising shape memory alloys which have been used for pipe joints but no previous work pays any attention to their biomedical application. Following the outline of the aforementioned development of biodegradable Fe-based alloys, we believe that it is worthwhile to investigate the feasibility of FeMnSi alloy as biodegradable metal candidate, since element Si is widely used in biomedical metallic materials as an alloying element. A shape memory metallic material based on FeMnSi was obtained through classical melting method. The material was analyzed as cast and plastic deformed through rolling concerning materials microstructure (scanning electrons microscopy - SEM), chemical analyses (X-ray analyze by EDAX) and corrosion resistance (or biodegradation rate) in an artificial saliva electrolytic solutions (Fusayama) artificial aerated by linear and cyclic curves determination (potentiometry - VoltaLab).

Shape memory alloys (SMAs) are commonly used in micro-electro-mechanical systems (MEMS). Having the unique shape memory, super-elastic affects and now damping capacity SMAs have become an important smart material for a broad range of engineering applications in last years. Copper based SMAs are promising alloys, based on the obtaining price and good characteristic properties. Shape memory alloys as thin films are used for fast actuation in applications due to their high surface to volume ratio comparing to bulk SMAs. In this paper two shape memory alloys based on copper, proposed as targets in different deposition processes to obtain MEMS and with different chemical composition, are analyzed through scanning electrons microscope (SEM), XRD and EDAX considerations after water quenching and recovery heat treatments. The martensite variants are dimensioned and 3D aspects are also analyzed for both metallic materials. The metallic phases obtained after heat treatment are determined and compare in both thermal influenced cases.

A shape memory alloy with medical applications was analyzed by corrosion point of view in Ringer solution before and after a thermo-mechanical solicitation. Scanning electrons microscope, EDAX and Potentiostat equipments were used to characterize the material surface and his behavior during and after an electric polarization. Pitting corrosion type was observed on the surface with more accentuated aspects for the fatigued sample.

The reversibility of the phase transformation in shape-memory alloys (SMAs) directly governs the mechanical response of these materials. Infrared thermography is used in this study to measure the mechanical dissipation produced by copper-based SMAs under cyclic loading at ambient temperature. Several specimens with different chemical compositions are tested. Mechanical dissipation which is produced by the material is deduced from the temperature change using a 0D version of the heat equation. Results obtained show that the chemical composition as well as the nature of the phase involved (martensite or austenite) influence the mechanical dissipation produced by the specimens during cyclic mechanical loading.

The class of biomaterials (metallic, polymer or ceramics) has applications as implants with a temporary function. Among magnezium (high corrosion rate) and iron (slow corrosion rate) based biodegradable alloys a new class based on zinc try to fullfill the gap between the first two alloy systems concerning the degradation rate. The role of these alloys is to provide some specific characteristics for a limited period of time. In this article preliminary results based on microstructural and chemical characteristics of a Zn-Mg alloy are presented. The results were obtained using optical and electronic microscopy (MO and SEM) and dispersive energy spectroscpy (EDS) and X-ray difraction (XRD).

Biodegradable alloys are very attractive biomaterials. Electrochemical impedance spectroscopy (EIS) and linear potentiodynamic polarization (LPP) techniques were used for the study of the electrochemical behavior of uncoated FeMnSi and coated FeMnSi with hydroxyapatite + zirconia (HA-ZrO2) through pulsed laser deposition (PLD) technique. Experiments were carried out using Hank’s balanced salt solution (HBSS). It has been shown that in HBSS the impedance for uncoated FeMnSi was mainly characterized by one capacitive effect, which related to the alloy charge transfer control. The charge transfer resistance increases for HA-ZrO2-coated FeMnSi alloy. The equivalent circuits simulating the electrochemical behavior of both uncoated and HA-ZrO2-coated FeMnSi alloys in HBSS were proposed. From LPP the corrosion resistance was evaluated by means of the zero current potential (ZCP) and corrosion current density (jcorr). The surface morphology of both uncoated and HA-coated FeMnSi alloys in HBSS obtained after LPP was studied using scanning electron microscopy (SEM).

Materials engineering involves knowledge of the fundamental physics, chemistry and engineering of materials in order to elaborate, develop, and use materials with superior and new properties. The research, development and applications of materials are the major reasons behind the availability, cost reduction, innovations and improvements in all the fields of industry. Master's programs are designed to give you a solid (strong) education in the materials engineering field. Students entering a Master program have already earned a bachelor's degree and have solid acquirement of engineering. The program entails coursework, examinations and an internship or other applied experience. A master report is required to obtain the masters degree based on the researches during the stage. During a Master programme the students learn to approach complex issues from the perspective of different disciplines such as: characterisation of materials, thermodynamics, structurals transformations, technology of materials, properties of surfaces or initiation on research methods. By understanding the properties of materials, materials engineers create new materials with desired properties. Students entering a Ph.D. program have already earned a a masters degree in the field of „Materials engineering". Because of the nature of specialization the Ph.D. program tends to be smaller than master program. The international orientation of the practice stage approaches to of the Erasmus mobilites. A Ph.D. typically demonstrates a person's competence in research. Ph.D. students begin by taking courses and exams, go on to taking advanced seminars and preparing dissertation research. To complete their knowledges, they are continuing by researching, writing and completeing a dissertation thesis. The doctoral-level thesis, is the culmination of a Ph.D. candidate's research into a topic and is the major requirement of earning the doctorate. A doctoral degree is obviously a more advanced degree. However, it is long. Depending on the program, a PhD could take 4-8 years to complete. A PhD programs entails 3 years of coursework and a dissertation. During this these years the independent researchs projects are designed to cover new knowledge in your field and to be of publishable quality. Doctoral study offers the unique opportunity for an individual to develope intensive and prolonged research on a particular topic, which often leads to publication. The present paper presents the association of Romanian and French university teachers to educate students to prepare a Master diploma and to continue with cotutelle doctoral studies in the field of materials engineering.

A new shape memory alloy was obtain from high purity Cu, Mn and Al elements using a induce furnace. The intelligent material present negative transformation temperatures and an austenite like state at room temperature. The austenite state of CuMnAl shape memory alloy present superelasticity property. Five kilograms ingot was obtain of Cu10Mn10Al alloy. From the base material (melted state) were cut samples with 6 mm thickness using a mechanical saw. After an homogenization heat treatment the samples were hot rolled through four passes with a reduction coefficient of 20%. Experimental lamellas were obtained with 1.5 mm thickness and 90x10 mm length and width. After the hot rolled treatment the materials were heat treated at 800°C for 20 minutes and chilled in water. Four samples, one just laminated and three heat treated by aging, were analyzed with a Netzsch DMA equipment to establish the elastic modulus and the internal friction values of the materials. Metallic materials microstructure was analyzed using a scanning electron microscope Vega Tescan LMH II type. After the aging heat treatment a decrease of internal friction is observed on the entire analyze range which is assigned to formation of Al-based precipitates that block the internal movement of the alloy characteristic phases.

Some metallic materials exhibit good damping capacity of mechanical energy into thermal energy. This property along with the others metallic characteristics make this materials interesting for a big number of applications. These materials can be used as bumpers in different applications including automotive field. Beside grey cast iron and shape memory alloys few new metallic materials are presented for the supposition of high damping capacity. We analyze the causes that increase the internal friction of some metallic materials and possibilities to enhance this property through different mechanical, physical or chemical methods. Shape memory alloys, especially those based on copper, present a different damping capacity on martensite, austenite or transition state. In the transformation range M ↔A, which in case of copper base shape memory alloys is quite large, the metallic intelligent materials present a high internal friction, almost comparable with natural rubber behavior that can transform mechanical energy into thermal energy till a certain value of the external solicitation. These materials can be used as noise or small vibrations bumpers or even as shock absorbers in automotive industry.

The thermally and stress induced phase transitions occurring in a Cu-Al-Mn Shape Memory Alloy (SMA) have been investigated by means of thermal analysis techniques, tensile testing and microscopic observations. On heating a hot rolled solution annealed Cu-Al-Mn SMA, up to 873 K, two phase transformations, related to equilibrium phase precipitation and to 2-step order-disorder transition, respectively, were revealed by Differential Scanning Calorimetry (DSC). During tensile testing, the Cu-Al-Mn SMA under study experienced almost complete superelasticity, after five mechanical training cycles, as well as good ductility and tensile resistance. On trained specimens the formation of stress induced martensite was revealed by optical microscopy (OM) observations. The reversion to austenite of stress induced martensite was accompanied by relatively large increases of elastic modulus and internal friction, determined on Dynamic Mechanical Analyzer (DMA) and by marked variations of relative elongation, thermal expansion coefficient and elongation rate, determined by dilatometry. Since it is a two step transition, it was associated with the two morphologies of stress induced martensite observed by Scanning Electron Microscopy (SEM).