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In this work, a post treatment of laser surface melting (LSM) has been employed on Stellite 6 and 10 wt.% Mo-alloyed Stellite 6 hardfacings deposited by plasma transferred arc (PTA) process. LSM process refined the microstructures of both hardfacings, while favoring a network-like complex carbide dominated microstructure in the Mo-alloyed version. With reference to the PTA Stellite 6 hardfacing, LSM process led to an increment in surface hardness albeit a subsequent reduction of wear loss at room temperature, where abrasive wear mechanism was dominant. At 500 °C, oxidative wear contributed to the progress of wear by favoring CoO and Co3O4 type tribo-oxides on the contact surfaces of the PTA and LSM’ed hardfacings, respectively. However, Co3O4 type tribo-oxides exhibited poor mechanical stability, than CoO, which led to easier removal from the contact surface and aggravated the wear loss by abrasive wear mechanism. In this respect, LSM’ed hardfacings exhibited higher wear loss than PTA Stellite 6 hardfacing at 500 °C, unlike room temperature.

This work has been initiated with the aim of increasing the success of micro-arc oxidation coatings fabricated on aluminium alloys against degradation under sliding contact conditions at high temperatures. For this purpose, the 7075 Al alloy has been micro-arc oxidised in an aluminate-based electrolyte with or without the adding monoclinic ZrO2 particles. Microstructural analyses revealed that the coating synthesised in a ZrO2-added electrolyte consisted of a ZrO2 particles participated Al2O3-based outer layer and a monolithic Al2O3-based inner layer, which exhibited similar features with that of the synthesised in the ZrO2-free aluminate-based electrolyte. Moreover, the coating fabricated in the ZrO2-added electrolyte exhibited enhanced wear resistance during the dry sliding wear tests conducted at room temperature and had higher durability during the tests done at 300 degrees C. Since the examined coatings were worn by fatigue wear mechanism, their durability during high temperature wear tests was analysed by using the conventional stress-based fatigue approach. From the derived equations, the maximum contact pressures at which coatings can endure 106 contact cycles at 300 degrees C were estimated as 851 and 331 MPa for the coatings fabricated in the ZrO2-added and ZrO2-free aluminate-based electrolytes, respectively.

Tento článek si klade za cíl porozumět mikrostrukturním změnám v Plasma Transfer Arc (PTA) naneseném tvrdokovem z vysokorychlostní oceli (HSS) M2 po zabudování 10% hmotn. Mo legování během nanášení s následným tavením laserového povrchu. Tvrdé povrchové úpravy uložené PTA byly vyrobeny na 4140 oceli. Potom byly Mo legované a nelegované PTA depozity podrobeny procesu laserového povrchového tavení (LSM). U všech výsledných struktur byla provedena komplexní mikrostrukturální charakterizace. Ke zjištění struktury matrice a morfologie karbidů byla použita optická metalografie s použitím vhodných leptacích činidel a SEM mikroskopie ve spojení s technikami XRD. Mikrostruktura PTA byla blízká rovnovážné struktuře M2 HSS obsahující směs feritu / austenitu / martenzitu spolu skarbidy typu MC, M2C a M6C. Zatímco LSM M2 HSS způsobil vyšší podíl martenzitu a jemnějších zrn ve struktuře, což mělo za následek zvýšení tvrdosti. Přidání 10% hmotn. Mo mění karbidy z MC a prutů jako M2C na vláknité M2C a rybí kosti jako M6C. LSM depozit M2 HSS PTA legovaných Mo vedlo k celkovému snížení podílu karbidů M6C a vláknitých karbidů M2C doprovázených poklesem tvrdosti. The article aims to comprehend the microstructural changes, in Plasma Transfer Arc (PTA) deposited M2 high speed steel (HSS) hardfacings upon incorporation of 10wt% Mo alloying during deposition followed by laser surface melting. PTA deposited hardfacings were produced over 4140 steel. Then Mo alloyed and unalloyed PTA deposits were subjected to laser surface melting (LSM) process. A comprehensive microstructural characterization for all the resultant structures was carried out. Optical metallography using appropriate etching reagents and SEM microscopy in conjunction with XRD techniques were employed to ascertain the matrix structure and carbides morphology. The PTA microstructure was close to equilibrium structure of M2 HSS containing mixture of ferrite / austenite / martensite along with MC, M2C and M6C type carbides. While the LSM of M2 HSS caused higher fraction of martensite and finer grains in the structure resulting in increment in hardness. 10-wt% Mo addition changes the carbides from MC and rod like M2C to fibrous M2C and fishbone like M6C carbides. The LSM of Mo alloyed M2 HSS PTA deposits led to an overall decrease in the fraction of M6C carbides and fibrous M2C carbides accompanied by a decrease in hardness.

Plasma electrolytic oxidation (PEO) treatment of Mg alloys improves their wear resistance by increasing their surface hardness, but also leads to high coefficient of friction (COF) values. The sliding counterfaces and the conditions under which PEO-coated Mg alloys operate affect their COFs. PEO-coated AZ31 alloy sliding against hydrogenated DLC (a-C-H) coated steel yields a low COF of 0.13 under the ambient conditions. The current study investigates the effect of the test temperature on the tribological behavior of PEO-coated AZ31 Mg samples sliding against the a-C-H coated counterface at temperatures up to 300 °C. According to the COF vs. wear rate diagram constructed in the temperature range of 25–250 °C, lower COF values and wear rates were exhibited by PEO-coated AZ31 sliding against a-C-H compared to uncoated AZ31 sliding against a-C-H, and PEO coated AZ31 sliding against an uncoated ASTM 52100 steel. The PEO-coated AZ31 produced the lowest COF of 0.03 at 200 °C. The application of PEO to the Mg alloy automotive cylinder bores running against DLC-coated piston rings and/or PEO-coated Mg alloy pistons running against DLC-coated bores could provide a new approach for the prevention of seizure and hot scuffing in lightweight engines in the temperature range between 150–250 °C.

This study focuses on the surface modification of a medical grade Co-Cr alloy via combining cold spray and thermal oxidation processes. After deposition of a Ti96-Al4 (wt.%) coating, samples were oxidized at 600 degrees C for 60h in air. Oxidation transformed the coating into a dual-layered structure comprising an outer oxide layer (mainly rutile) with a diffusion layer (mainly oxygen enriched titanium and Ti-Al intermetallics) beneath it. Formation of new phases made the diffusion layer brittle and prone to fracture during pull out tests. Scratch and Rockwell-C tests confirmed good adhesion between the oxide and underlying diffusion layers, having average hardness as 1297 HV and 387 HV, respectively. The dual-layer coating exhibited excellent wear performance in a 0.9wt.% NaCl solution against sliding action of alumina ball as compared to Co-Cr substrate, especially at contact pressures

Vliv legování (10 wt% Mo) a následného zpracování povrchu (laserové přetavení povrchu) na vlastnosti a chování byl hodnocen u PTA návaru oceli M2. Vlivem legování Mo došlo ke změně charaketru a povahy jak matrice, tak karbidů v povlaku M2. Naopak, laserové zpracování vedlo ke zjemnění struktury a potalčení precipitace karbidických částic. Navzdory zvýšení povrchové trvrdosti vykazoval povlak po laserovém zpracování pokles odolnosti proti opotřebení. Naopak, návar legovaný Mo zlepšil odolnost proti opotřebení, ačkoli jeho tvrdost poklesla. Důvodem byla tvorba oxidického tribofilmu typu Magneli v Mo legované oceli. The influence of alloying (10 wt% Molybdenum) and post deposition treatment (Laser Surface Melting) on the structural characteristics and wear performance of Plasma Transfer Arc deposited M2 hardfacings have been investigated. The nature of matrix and carbides of M2 hardfacing had changed upon Molybdenum addition while the Laser Surface Melting caused structural refinement and a decrease in carbide volume fraction. Despite an increase in hardness, Laser Surface Melting has resulted in reduction in sliding wear resistance against alumina counterface, while the Molybdenum enhanced the wear resistance even with decrease in hardness. This counter intuitive behaviour is attributed to Magnelli oxide containing tribo-oxide layer formation on the worn surface of Molybdenum alloyed hardfacings.

In the present work, the influence of alumina (Al2O3) and zirconia (ZrO2) incorporation on the structural properties and wear resistance of titania (TiO2) based micro-arc oxidation (MAO) coatings fabricated on Ti6Al4V alloy was studied. For this purpose MAO was employed in a silicate-based electrolyte with and without additions of Al2O3 and ZrO2 particles. The structural properties were determined via X-ray diffraction (XRD) and X-ray photoelectron (XPS) spectroscopy analysis and an energy dispersive spectrometer (EDS) equipped scanning electron microscope (SEM). Furthermore, thermochemical simulations were made by using FactSage 7.3. Mechanical properties of the MAO coatings were determined by hardness measurements and dry sliding reciprocating wear tests. Structural examinations revealed that the MAO coatings fabricated in Al2O3 and ZrO2 added electrolytes comprised of these oxides and their complex forms (Al2TiO5 and ZrTiO4, respectively) along with TiO2 and amorphous silica (SiO2). Although incorporations of Al2O3 and ZrO2 did not remarkably improve the hardness of the MAO coatings, the highest wear resistance was obtained from the one formed in the ZrO2 added electrolyte. On the other hand, the MAO coating fabricated in the Al2O3 added electrolyte exhibited lower wear resistance than that of fabricated in the particle-free silicate-based electrolyte.

This study aims to understand the oxide scale formation on the surfaces of commercial and Mo (10wt.%)-modified Stellite 12 hardfacings deposited on 4140 steel. For this purpose, samples of the hardfacings were isothermally oxidized in air at various temperatures in between 500 and 900 degrees C for 30 h. As a result of changes in the microstructure upon Mo addition, about 50% higher mass gain at all oxidation temperatures was observed. The characteristics of the developed oxide scales were examined by utilizing Raman spectroscopy, scanning electron microscopy and x-ray diffraction analysis. The oxide scale formed over Stellite 12 consisted of CoO-, Co3O4- and Cr2O3-type oxides, while additionally CoMoO4-type complex oxide was detected on Mo-modified hardfacing, more likely at the alloy-scale interface. On the basis of findings of isothermal oxidation tests, the formation mechanisms of this complex oxide imposing better wear resistance as reported in our previous studies were explained during high-temperature wear testing, i.e., dynamic oxidation conditions.

This study reports on the consolidation of niobium boride powders by cold pressing/pressureless sintering (PS, with or without Co addition) and spark plasma sintering (SPS) techniques. Niobium boride powders (containing NbB, Nb3B4 and NbB2 phases) which were mechanochemically synthesized from Nb2O5, B2O3 and Mg blends and purified by HCl leaching were used as precursor material. The effects of different sintering techniques on the consolidation behaviour, microstructure, densification rate and mechanical properties (microhardness, wear characteristics, elastic modulus, indentation response and fracture toughness) of the bulk products were investigated. PS with Co addition resulted in superior properties than those yielded after PS without Co addition and SPS. Bulk niobium boride products having relative density of 93-98%, microhardness of 24-28 GPa, wear volume loss of 2.8-4.5 x 10(-4) mm(3), elastic modulus of 508-552 GPa and fracture toughness of 4.05-4.74 MPa m(1/2) were obtained by Co (2 or 5 wt.%) activated PS at 1500 degrees C., Scientific and Technological Research Council of Turkey (TÜBİTAK)

Structural and mechanical properties of La 2 O 3 added (up to 5 wt%) t-ZrO 2 compacts were examined with the aim of optimizing hardness and fracture toughness for room temperature applications. Structural examinations were performed using an X-ray diffractometer and a scanning electron microscope. Mechanical properties of the compacts were determined as modulus of elasticity, hardness and fracture toughness by conducting Vickers indentation tests under test loads of 0.5, 1 and 10 kg. Addition of 0.5 wt% La 2 O 3 deteriorated the room temperature stability of t-ZrO 2 by forming m-ZrO 2 and coarse polygonal grains in the matrix. Higher concentrations (2 and 5 wt% La 2 O 3 ) caused precipitation of La 2 Zr 2 O 7 at the grain boundaries, which also accompanied by a reduction in hardness. Fracture toughness increased with increasing La 2 O 3 content of the compact. Finally, an optimum combination between hardness and fracture toughness was obtained for the 0.5 wt% La 2 O 3 containing compact.

The present work studies microstructure and wear resistance of Stellite 12 alloy coating deposited on quenched and tempered AISI 4140 steel substrate using plasma transferred arc (PTA) hardfacing method. The X-ray diffraction, scanning electron microscopy (SEM) micrographs and energy-dispersive X-ray (EDX) analysis indicated that Stellite12 mainly consists of solid solution phase (α-Co, e-Co), chromium-rich carbides (Cr7C3, Cr23C6) and tungsten-containing compounds. The wear properties of PTA hardfaced stellite12 comparing with AISI 4140 steel at room temperature (RT) were investigated by using the ball-on-disc type tribotester. It has been found that the Stellite12 hardfacing coating exhibits superior wear resistance than substrate during dry sliding wear test at RT.

This study has been carried out to optimise the silver (Ag) content of the coating synthesised on commercially pure titanium (Cp-Ti, Grade 4) for biomedical applications by micro-arc oxidation (MAO) process. The MAO process has been conducted in electrolytes containing silver acetate (AgC2H3O2) at different concentrations between 0 and 0.002 mol L-1. When compared to the base electrolyte, coatings synthesised in >= 0.001 mol L-1 AgC2H3O2 added electrolytes exhibited an antibacterial efficiency of 99.8% against Staphylococcus aureus (S. aureus). Detailed examination revealed that the presence of 0.01 mol L-1 AgC2H3O2 in the electrolyte resulted in incorporation of 1.4 wt-% Ag into fabricated coating consisting mainly of outer hydroxyapatite (HA) and inner titanium oxide (TiO2) layers. In comparison to the Ag-free coating, 1.4 wt-% Ag in the coating lowered the proliferation of SAOS-2 cells, which still tended to grow at a relatively low rate with increasing culturing time.

Al doped ZnO (ZnO:Al) thin films were prepared using a sol-gel dip coating technique and deposited on borosilicate glass substrates. The irradiation treatment, was conducted using Co-60 radioisotope, played an important role in enhancing electrical properties. The absorbed dose was a key parameter to decrease the electrical resistivity and to increase carrier density and carrier mobility of nanospherical ZnO:Al thin film. ZnO:Al thin film with the doping of Al at 0.8 at% had the lowest electrical resistivity and the highest optical transmittance after the irradiation treatment. Optical properties, such as transmittance and reflectance, were affected at an absorbed dose of 0.2 Gy. The curves of optical density were improved at similar to 380, 420, and 520 nm in visible range after the irradiation process. Besides, another characteristic optical density band between similar to 900 and 1100 nm was enhanced by gamma irradiation. It has been suggested that the mechanism of absorption is related to an allowed direct transition at the irradiated ZnO:Al thin film on borosilicate glass. The optical band gap of the ZnO:Al thin films broadened with increasing doping concentration. However, there is a decrease in optical energy gap of ZnO:Al thin film along with the absorbed dose of the film. (C) 2013 Elsevier Ltd. All rights reserved.

Doped ZnO:Al thin films were deposited on glass substrates by the solgel dip technique. Optical parameters such as the refractive index and the extinction coefficient tend to change with increasing annealing temperature.

Air oxidation behaviour of a Ti–6Al–4V alloy was examined over the temperature range of 600–800 °C for different time intervals ranging between 0.5 and 72 h. In addition to the determination of the oxidation kinetics by weight gain measurements, oxygen diffusion zone (ODZ) depth and hardness measurements were conducted on the cross-sections of the oxidised alloys to investigate the diffusion kinetics of oxygen into the substrate. The rate of oxidation evaluated according to the weight gain measurements fitted parabolic kinetics between 600 and 700 °C and linear kinetics above 700 °C by yielding activation energies of 276 and 191 kJ/mol, respectively. Analysis of the ODZ depth and hardness measurements resulted in an activation energy of 202 kJ/mol for oxygen diffusion in Ti–6Al–4V alloy. Finally, the kinetics of oxidation and oxygen diffusion were evaluated by the analysis of the experimental data with respect to temperature-compensated time parameter.

The addition of 10 wt% Mo encouraged a eutectic reaction to form Co6Mo6C complex carbide and Co3Mo intermetallic in addition to Cr23C6 while causing solid solution hardening of the Co-rich dendritic matrix in the microstructure of the PTA deposited Stellite 12 coating. The addition of molybdenum not only imposed a higher hardness but also enhanced wear resistance. Under oxidation dominated wear conditions (500 and 700 degrees C), the addition of molybdenum provided a remarkable increase in wear resistance in comparison to the lower temperatures (RT and 300 degrees C), due to the development of a protective oxide film on the worn surface. (C) 2015 Elsevier Ltd. All rights reserved.

In this study, comparative investigation of thermal oxidation treatment for Ti-6Al-4V was carried out to determine the optimum oxidation conditions for further evaluation of corrosion-wear performance. Characterization of modified surface layers was made by means of microscopic examinations, hardness measurements and X-ray diffraction analysis. Optimum oxidation condition was determined according to the results of accelerated corrosion tests made in 5m HCl solution The examined Ti-6Al-4V alloy exhibited excellent resistance to corrosion after oxidation at 600 degrees C for 60 h. This oxidation condition achieved 25 times higher wear resistance than the untreated alloy during reciprocating wear test conducted in a 0.9% NaCl solution.

In the present study, the formability of cold rolled and annealed steel sheets having carbon equivalent values in the range of 0.028 to 0.098 wt% were investigated. The steel sheet having the lowest carbon equivalent was a titanium-stabilized interstitial free steel, which established the highest strain hardening exponent, anisotropy coefficient and higher Forming Limit Diagram (FLD). Since plain strain intercept (FLD 0 ) is the most critical strain limit on the FLD, the empirical equations were derived between FLD 0 and microstructural features and mechanical properties. As a microstructural feature grain size and as a mechanical property anisotropy coefficient gave the most reliable correlations.

This is an investigation on examination of deformation induced surface roughening behavior of two AISI 304 quality austenitic stainless steel sheets, having ASTM grain size numbers of 7 and 8. In as-received condition, surface roughness of the fine-grained steel was higher than that of the coarse-grained steel, where the roughness increased gradually during plastic deformation. The rate of roughening increased with increasing grain size. Coarse-grained steel exhibited rougher surface than fine-grained steel after longitudinal strain of 11 %, during uniaxial tensile loading.

In this study, tensile and abrasive wear performances of two different quality as-cast ductile irons have been examined at various temperatures between 25 and 600°C. Tensile tests were carried out with a strain rate of 3×10 -4 /s. Wear tests were performed under a compression stress of 5.7 N/mm 2 , by rubbing samples on 125 μm Al 2 O 3 abrasive grains. In the temperature range of 100-300°C, where serrated flow is observed during tensile testing, tensile strength values of both ductile irons were invariable. Above 400°C, further increase of temperature caused dramatic decrease in tensile strength. As a general trend, abrasive wear resistances of the both ductile irons increased with increasing tensile strength. Exceptionally, maximum resistance to abrasive wear is obtained from both ductile irons at 100°C, probably due to dynamic strain aging.

rradiation of ZnO:Al thin film by reactor neutrons with neutron/gamma ratio at 1.44x104 (n.cm-2.s-1.mR-1) leads to a decrease in resistivity in this material. The observed effects in electrical resistivity are attributed to irradiation-induced formation of defects in the ZnO:Al thin film structure.

Al-doped, zinc oxide (ZnO:Al) films with a 1.2 at.% Al concentration were deposited on p-type silicon wafers using a sol-gel dip coating technique to produce a ZnO:Al/p-Si heterojunction. Following deposition and subsequent drying processes, the films were annealed in vacuum at five different temperatures between 550 and 900 degrees C for 1 h. The resistivity of the films decreased with increasing annealing temperature, and an annealing temperature of 700 degrees C provided controlled current flow through the ZnO:Al/p-Si heterojunction up to 20 V. The ZnO:Al film deposited on a p-type silicon wafer with 1.2 at.% Al concentration was concluded to have the potential for use in electronic devices as a diode after annealing at 700 degrees C. (C) 2012 Elsevier B.V. All rights reserved.

Al-doped n-ZnO/p-Si heterojunctions were fabricated using a sol-gel dip coating technique at 700 degrees C, in a nitrogen ambient. The structural, optical, and electrical properties of ZnO:Al thin films, and the heterojunction properties of ZnO:Al/p-Si were investigated with respect to the effects of Al doping concentration. Hexagonal nanostructured ZnO: Al thin films with a 1.2% and a 1.6 at.% Al concentration exhibited high optical transmittance in visible ranges. Electrical resistivity changed with respect to Al doping concentration, and minimum resistivity was detected at a 1.2 at.% Al concentration. The ZnO: Al/p-Si heterojunction properties were analysed using current-voltage (I-V) measurements at four different Al concentrations, ranging from 0.8 to 1.6 (at.%). The ZnO: Al/p-Si heterojunctions exhibited diode-like rectifying behaviour. Under UV illumination, the photoelectric behaviour observed for the ZnO: Al/p-Si heterojunctions was diode.

Wear and biological performances of a thermally oxidized Ti6Al7Nb alloy were investigated. Thermal oxidation (TO) performed at 600 degrees C for 60 h in air formed a 0.6 mu m thick and relatively rough (having an average surface roughness of 1.1 mu m) oxide layer (OL) on the surface. The OL was identified as the rutile form of TiO2 and there was an oxygen diffusion zone (ODZ) with an average thickness of 5 mu m just beneath it. The applied TO process resulted in more than ten-fold increase in wear resistance in a simulated body fluid (SBF) solution. Additionally, the biological performance was also enhanced as revealed by SBF immersion and cell culture tests.

In the present study, the in-vitro biological responses of two competitive titanium alloys (Ti6Al4V and Ti6Al7Nb) were investigated after modifying their surfaces by the micro-arc oxidation (MAO) process conducted in a (CH 3COO)2Ca•H2O and Na3PO 4 containing electrolyte under identical electrical parameters and exposure time. After the process, the surfaces of the alloys were covered with a thick (approx. 10 µm) TiO2 layer exhibiting different characteristics. The oxide layer of the Ti6Al4V alloy was porous and contained hydroxyapatite precipitates whereas the oxide layer of the Ti6Al7Nb alloy showed a more grainy appearance and contained calcium titanate precipitates. Simulated body fluid (SBF) and cell culture tests were conducted to compare the biological performance of the alloys. Even though oxidized alloys exhibited somewhat similar response in SBF tests, the number of SAOS-2 cells attached to the oxide layer of the Ti6Al4V alloy was greater than that of the T6Al7Nb alloy. © 2011 Elsevier Inc. All rights reserved. Consejo Nacional de Investigaciones Científicas y Técnicas 105M062 The authors greatly acknowledge financial support provided by The Scientific and Technical Research Council of Turkey (TUBITAK) under contract no. 105M062 . The MAO equipment used in the present work was supplied by the State Planning Organization of Turkey through project no. 90158.

This study was conducted to evaluate the effect of TiO2 + MnO2 and MgO + Cr2O3 additions on the wear resistance of alumina based ceramic nozzles sintered at 1550degreesC for 1 h. Wear performance of the nozzles was determined by recording their weight loss during electrostatic enameled coating process. When compared to pure alumina nozzles, 0.5 % MgO + 1.2 % Cr2O3 addition improved the wear resistance by about 35 %.

The copper indium gallium diselenide Cu(In,Ga)Se 2 (CIGS) thin-films deposited on soda lime silica glass substrates were dip-coated five times and annealed at 180 o C. The advantages of CuIn(Ga)Se 2 thin films were its wide compositional tolerance, high conversion efficiency, flexibility, low cost of materials and high optical absorption in the visible spectrum. The effect of the withdrawal speed, on the optical properties of the CIGS thin films derived by sol-gel process detailed clearly in this study by transmission and reflection measurements with controlling the withdrawal speed. The prepared CIGS thin films had p-type conductivity. The significant blue shift of absorption edge as well as tuning of optical band gap was observed with the withdrawal speed. The CIGS thin films at four different withdrawal speeds were such as 60, 120, 200 and 300 mm min -1 prepared from colloidal suspensions to control the nature of nanospheres in the CIGS texture, because the colloidal solution was utilised as a template to control the particle shape.

Optical characterisitcs of ZnO:Al thin films deposited on soda lime glass was analysed depending on the annealing temperature and irraditaion by Cs-137 with 661.66 keV photon energy. Annealing temperature was varied in between 350 and 500 degrees C. The thickness of the film was reduced with increasing annealing temperature. Irradition increased the absorbsion while reducing the transmittance.

TWIP (Twinning-induced Plasticity) steels have exceptionally good combinations of strength, ductility and damage tolerance which satisfy the recent requirements of automotive industries. Firstly, TWIP has the most beneficial effect on the work-hardening. It is believed that deformation twins increase the work-hardening rate by acting as obstacles against gliding dislocations. Moreover, TWIP steels have low to intermediate stacking fault energy and hence undergo extensive mechanical twinning during deformation, which in turn leads a good combination of both strength and ductility. To explain the mechanical characteristics and the mechanical behavior of the TWIP steels, we have been made some investigations and experiments that show the effects of microalloying elements and deformation mechanisms. In this study, three different compositions of TWIP steels have been produced. The microstructure and mechanical properties are characterized by using optical, electron microscopy and mechanical tests.