Papers by Keyword: Fe-Based Alloy

Abstract: 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.

Abstract: This paper presents the alloyability of FeCrCu powder compacts formed through warm powder compaction route. A lab-scale uni-axial die compaction rig was designed and fabricated which enabled the powder forming at elevated temperature. Iron powder ASC 100.29 was mechanically mixed with other alloying elements, i.e., copper (Cu) and chromium (Cr) as well as carbon (C) as additive for 60 minutes. Green samples were formed at 30°C (room temperature), 100°C, and 180°C through simultaneous upward and downward axial loadings. The defect-free green compacts were subsequently sintered in argon gas fired furnace at 900°C and 1000°C for 60 minutes at a rate of 5°C/minute. The alloyability of the sintered products was analyzed through XRD testing. The compressive strength of the sintered samples was also measured. The results revealed that FeCrCu alloy was formed at different intensity depended upon the forming and sintering temperature. The compressive strength was found to be highest for sample formed at 180°C and sintered at 1000°C.

Abstract: 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.

Abstract: Fe-based alloy coatings were produced by the plasma transferred arc(PTA) at arc current values of 90A,100A,110A and 120A. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and optical microscopy (OM) were used to characterize the microstructure of the coatings. The wear resistances of the coatings were tested by impact and wear experiment. The results show that, the coating and substrate are metallurgy combination, and the coating modified at 110A shows that better wear resistance than others.

Abstract: The work presents the structural, thermal and magnetic properties analysis of Fe72B20Si4Nb4 bulk metallic glasses in as-cast state and crystallization study of bulk amorphous alloy after annealing process. The studies were performed on bulk metallic glasses in of rods form with diameter of 1,5 and 2 mm. The structure analysis of the samples in as-cast state and phase analysis of studied alloy after annealing process was carried out by the X-ray diffraction (XRD) methods. Mössbauer spectroscopy (MS) was also used to investigate the local structure for studied bulk metallic glasses. Thermal properties associated with glass transition, onset and peak crystallization temperatures was examined by differential scanning calorimetry (DSC). The soft magnetic properties examination of tested material contained initial magnetic permeability and disaccommodation of magnetic permeability.

Abstract: The production cost of amorphous alloys by vacuum induction melting (VIM) was very high. In order to reduce the cost, in this paper, alloys were prepared in alkaline crucible protected with different slags by Air induction melting (AIM). The comparison was found out between VTM and ATM in the research by using optical microscope (OM), scanning electron microscope (SEM), EDS, etc. Experimental results showed that Fe-Si-B alloys can be prepared by AIM with economic and technical feasibility.

Abstract: Powder of Fe₇₂Nb₄Si₁₀B₁₄ (%at) glassy alloy was obtained by gas atomization in order to investigate the possibilities of amorphous phase formation due to the high cooling rates (10³ 10⁵ K/s) involved in this process. The ratio between the gas volumetric and the metal mass flow rates used was 1.0, and nitrogen (N₂) was used as the atomization gas. The powder, sieved in different granulometric size ranges, was characterized through: X-ray diffratometry (XRD), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). Fe₇₂Nb₄Si₁₀B₁₄ (%at) bulk metallic glass (BMG) showed completely or partially glassy structure depending on the size range. The obtaining of powders with glassy structure that could be applied as shot penning powder particles and thermal spray feeding powder for metallic coatings or would make possible the production of bulk glassy materials by warm consolidation of such powders or even a millimeters thick deposit obtained by spray forming with glassy or metastable microstructure that would be very interesting considering applications as soft ferromagnetic parts.

Abstract: We Successfully Prepared the Rod Glassy Samples of (Fe_1-xCo_x)₇₆Si₉B₁₀P₅ (x = 0~0.4) Bulk Metallic Glass (BMG) with the Diameters up to 3.0 mm by Substituting Fe for a Small Amount of Co Element. A Certain Amount of Co Substitution for Fe Contributes to the Increase of the Glass-Forming Ability (GFA) while Maintaining Good Mechanical Properties (the Fracture Strength up to 3700 MPa). This Co-Added Ferromagnetic Bulk Glassy Alloy System Also Exhibits a Higher Saturation Magnetization of 1.49 T and Lower Coercive Force (H_c, 1.2 A/m). The Fe-Based BMGs with Alloying a Small Amount of Co Element Demonstrate Excellent Combination of High GFA, Good Soft-Magnetic Properties as Well as High Strength.

Abstract: Solidification processes of Fe-B and Fe-C eutectic alloys have been investigated by a time-resolved synchrotron x-ray diffraction under containerless cooling conditions using a conical nozzle levitation technique. To observe relative variations of structure from the undercooled liquid to crystalline phase, we have conducted millisecond order time-resolved x-ray diffraction experiments with a two-dimensional detector. The structural variations observed during the solidification of the Fe₈₃C₁₇ alloy were identified as the phase transformation process expected from the Fe-C phase diagram. As for the Fe₈₃B₁₇ alloy, it was revealed that a metastable phase composed of Fe₂₃B₆ compound was precipitated as a primary crystalline phase from the undercooled liquid. In addition, decomposition of the metastable Fe₂₃B₆ phase showed dependence on the cooling rate of the sample. At the cooling rate of 30 K/s, the Fe₂₃B₆ phase decomposed to bcc-Fe and Fe₂B phases with decreasing temperature. On the contrary, at the cooling rate of 180 K/s, the metastable Fe₂₃B₆ phase remained in spite of an appearance of the bcc-Fe phase. By comparing the primary crystalline phase between the Fe₈₃C₁₇ and the Fe₈₃B₁₇ alloys, we suggest that the formability of the metastable Cr₂₃C₆-type compound is closely related with the glass-forming ability of Fe-metalloid binary alloys.

Abstract: The amplitude frequency response characteristics of simple beams made by Fe-Mn damping alloy, Fe-Cr-Mo damping alloy and 0.45C-steel under forced vibrations were studied using forced vibration measurement instrument. The results indicated that at forced vibration condition, the damping behaviors of Fe-Mn and Fe-Cr-Mo alloy beams were that the resonance amplitude and the resonance frequency range were reduced. The higher the exciting force was, the better the damping capacity of Fe-Mn alloy beam was, so it was suitable for the environment where higher vibrating force and shock existed. Whatever the exciting force was high or low, the damping capacity of Fe-Cr-Mo alloy beam was higher than 0.45C-steel, so it was more suitable for the environment where the strain amplitude changed in a wide range.