فهرست مقالات Ti-6Al-4V Alloy

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  1 - Application of the Relevance Vector Machine for Modeling Surface Roughness in WEDM Process for Ti-6Al-4V Titanium Alloy
  Abolfazl Foorginejad Nader Mollayi Morteza Taheri
  Cutting the Titanium alloys is a complicated task which cannot be performed by traditional methods and modern machining processes, such as Wire electro-discharge machining (WEDM) process which are mainly used for this purpose. As a result of the high price of the Ti-6Al چکیده کامل

  Cutting the Titanium alloys is a complicated task which cannot be performed by traditional methods and modern machining processes, such as Wire electro-discharge machining (WEDM) process which are mainly used for this purpose. As a result of the high price of the Ti-6Al-4V alloy, proper tuning of the input parameters so as to attain a desired value of the surface roughness is an important issue in this process. For this purpose, it is necessary to develop a predictive model of surface roughness based on the input process parameters. In this paper, The Taguchi method was used for the design of the experiment. According to their effectiveness, the input parameters are pulse-on time, pulse-off time, wire speed, current intensity, and voltage; and the output parameter is surface roughness. However, a predictive model cannot be defined by a simple mathematical expression as a result of the complicated and coupled multivariable effect of the process parameters on the surface roughness in this process. In this study, application of the relevance vector machine as a powerful machine learning algorithm for modeling and prediction of surface roughness in wire electro-discharge machining for Ti-6Al-4V titanium alloy has been investigated. The predicting result of model based on the root means square error (RMSE) and the coefficient of determination (R2) statistical indices, prove that this approach provides reasonable accuracy in this application. پرونده مقاله
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  2 - Microstructure Investigation and Mechanical Properties of Resistance Upset Butt Welded Ti-6Al-4V Alloy
  Mahmood Sharifitabar
  10.30495/admt.2020.1891939.1170
  In the present study, resistance upset butt welding was used as a solid-state process for joining Ti-6Al-4V alloy. Results showed that melting and subsequent solidification of the alloy at the joint interface promoted the development of a cast microstructure along with چکیده کامل

  In the present study, resistance upset butt welding was used as a solid-state process for joining Ti-6Al-4V alloy. Results showed that melting and subsequent solidification of the alloy at the joint interface promoted the development of a cast microstructure along with some pores. However, by applying the constant upset pressure of 1.62 MPa, the pore volume fraction decreased considerably with decreasing the welding current from 110 A/mm2 to 55 A/mm2. Hardness test results showed that the weld interface and the base material had the highest (352 HV) and the lowest (318 HV) values, respectively. The microstructure of the interface consisted of ά martensite and Widmanstätten laths. The tensile strength of the joints varied between 550 and 883 MPa depending on the welding parameters used. In the optimum condition, the maximum strength of the joint was about 94% of the base metal strength. Fractography of samples confirmed that the formation of pores deteriorated the strength of the joints. پرونده مقاله
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  3 - Fatigue and corrosion fatigue properties of Ti-6Al-4V implant grade titanium alloy in Ringer solution
  Mahmoud Hajisafari Arman Zare Bidaki Saeid Yazdani
  Nowadays modification of metallic biomaterials which are used as implants for bone and hard tissues replacement is considered as an important subject. In the current study, corrosion fatigue properties of Ti-6Al-4V alloy investigated via Rotating-Bending standard test m چکیده کامل

  Nowadays modification of metallic biomaterials which are used as implants for bone and hard tissues replacement is considered as an important subject. In the current study, corrosion fatigue properties of Ti-6Al-4V alloy investigated via Rotating-Bending standard test method and then, the results compared with the fatigue properties of the specimens tested in the same conditions. Scanning electron microscopy used to investigate the chemical composition (EDS- Energy-dispersive X-ray spectroscopy), microstructural features and crack propagation characteristics. Results showed that the presence of corrosive environment not only results in decrease in fatigue life, but also eliminates the fatigue limit. Further studies revealed that aggregation of corrosion products, with more hardness values, at the crack tip cause an obvious deviation of crack propagation from its main direction. Therefore, a tortuous crack path through the bulk of the specimens was detected concurrent with penetration of solution into the crack. In addition, dimensions and morphology of fatigue crack surfaces were completely different from corrosion fatigue cracks as well. پرونده مقاله
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  4 - Simulation of Plastic Deformation Behavior of Ti-6Al-4V Alloy by Finite Element Method
  E Amini F Madadi Sh Katani M Atapoor
  Mechanical properties of alloys have a strong relation with microstructure and determination of their behavior can lead to multiple advantages. To obtain this goal, finite element method )FEM( is one of the best ways. In this study a series of experiments were carried o چکیده کامل

  Mechanical properties of alloys have a strong relation with microstructure and determination of their behavior can lead to multiple advantages. To obtain this goal, finite element method )FEM( is one of the best ways. In this study a series of experiments were carried out on the produced Ti-6Al-4V to obtain its mechanical characteristics and to prepare it for photographing in micro dimensions. Next, using scanning electron microscopy (SEM), images were taken from some regions of the manufactured Ti-6Al-4V. In the next step, a method was developed to separate alpha-phases from beta-phases with a relatively high accuracy. At the end of this stage, the images were mapped into a matrix involving arrays which show the type of the phases. A code is written which maps the material matrices to the FEM model. The Gurson model is an appropriate model for simulating the damage inside the ductile material. Results of simulations obtained from SEM images show that the simulation data are in good agreement with experimental results and also analysis of simulation clearly shows that the failure always happens in boundaries between two different phases; ductile and brittle, and then growth over them to form the final failure of the material. پرونده مقاله