SYNTHESIS OF Mg-Cu-Y BULK METALLIC GLASS PLATE VIA SPRAY FORMING PROCESS

Abstract Temperature control is critical in manufacturing of the multifacet bulk metallic glass (BMG) knife edge. The temperature control in thermoplastic forming process could make a significant effect on the type of deformation, which ultimately results in the final blade edge shape. The controller selection is based on the knowledge of the model from system identification, the performance of the controllers, and the feasibility of the implementation to the testbed. In this study, temperature control, using fuzzy logic, is implemented along with auto-regressive exogenous, ARX model, which can maintain the steady-state temperature within the range of ±2.5 K. With this proposed controller, experiments have shown similar or better results of multifacet blade geometries than those manufactured using proportional–integral–derivative (PID) controller. The blade edge samples are successfully manufactured with the average straightness and the edge radius of the blade of 3.66 ± 0.5 μm and 25.7 ± 6 nm, respectively.

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Estimation of Micro-Formability and FEM Simulation of Micro-Forming Process of a Zr-Based Bulk Metallic Glass

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.2129 ◽

2007 ◽

Vol 539-543 ◽

pp. 2129-2134

Author(s):

Young Sang Na ◽

S.G. Kang ◽

K.Y. Park ◽

Jong Hoon Lee

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Fem Simulation ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Liquid Region ◽

Micro Forming ◽

Forming Process ◽

Rf Values ◽

Simulation Results

Micro-forming is considered to be a suited technology to manufacture very small metallic parts (several μm~mm). Zr-based bulk metallic glass, Zr62Cu17Ni13Al8, has been expected to be a promising metallic material for micro-forming process due to their isotropy, low flow stress in a wide supercooled liquid region and good stability of amorphous matrix. Therefore, one can expect that micro-forming of Zr62Cu17Ni13Al8 might be feasible at a relatively low stress in the supercooled liquid state without any crystallization during hot deformation. In this study, micro-formability of Zr62Cu17Ni13Al8 bulk metallic glass was investigated for micro-forging of U-shape pattern. Microformability was estimated by comparing Rf values (=Af/Ag), where Ag is corss-sectional area of U groove, and Af the filled area by material. Micro-forging process was also simulated and analyzed by applying the finite element method. The micro-formability of Zr62Cu17Ni13Al8 was increased with increasing load and time in the temperature range of the supercooled liquid state. In spite of the similar trend in the variations of Rf values, FEM simulation results showed much higher Rf values than the experimental Rf values. This disagreement was analyzed based on the stress overshoot phenomena of bulk metallic glasses in the supercooled liquid region. FEM simulation of the microstamping process was applicable for the optimization of micro-forming process by carefully interpreting the simulation results.

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Microstructure Formation on a Titanium-Based Bulk Metallic Glass Plate by Femtosecond Laser Irradiation

Ceramic Transactions Series - Characterization and Control of Interfaces for High Quality Advanced Materials III ◽

10.1002/9780470917145.ch8 ◽

2010 ◽

pp. 49-54

Author(s):

Masahiro Tsukamoto ◽

Togo Shinonaga ◽

Nobuhiro Matsushita ◽

Xinmin Wang ◽

Takeshi Wada ◽

...

Keyword(s):

Metallic Glass ◽

Femtosecond Laser ◽

Laser Irradiation ◽

Bulk Metallic Glass ◽

Glass Plate ◽

Femtosecond Laser Irradiation ◽

Microstructure Formation

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Finite element analysis on the micro-forming process of Zr-based bulk metallic glass

Proceedings of the 2012 IEEE 16th International Conference on Computer Supported Cooperative Work in Design (CSCWD) ◽

10.1109/cscwd.2012.6221904 ◽

2012 ◽

Cited By ~ 1

Author(s):

Qiang Yu ◽

Jun Wang ◽

Weijie Zhang ◽

Guanglan Liao

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

Micro Forming ◽

Forming Process ◽

Element Analysis

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Development of a Hybrid Thermoplastic Forming Process for the Manufacture of Curvilinear Surgical Blades From Bulk Metallic Glass

Journal of Micro and Nano-Manufacturing ◽

10.1115/1.4035389 ◽

2017 ◽

Vol 5 (1) ◽

Author(s):

James Zhu ◽

Shiv G. Kapoor

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Forming Process ◽

Face Surface ◽

Wide Range ◽

Thermoplastic Forming ◽

Blade Cutting ◽

20 Nm ◽

Force Profiles ◽

Positive Results

A hybrid thermoplastic forming process involving sequential micromolding and microdrawing operations is developed to manufacture the multifacet/curvilinear geometries found on most surgical blades. This is accomplished through an oblique drawing technique, i.e., drawing with a nonzero inclination angle. By applying time-varying force profiles during the drawing operation, a wide range of complex blade geometries is possible. Experiments have exhibited positive results across several multifacet and curvilinear blade geometries. Manufacturing process capabilities are quantitatively evaluated and experimental results have measured the bulk metallic glass (BMG) blade cutting edge radii to be consistently less than 15 nm, rake face surface roughness Ra to be on the order of 20 nm, and edge straightness deviations to be less than 5 μm root-mean-square (RMS) while retaining an amorphous atomic structure.

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Rapid Solidification and Laser Cladding of Gas Atomized Ni-Nb-Sn Bulk Metallic Glass

Materials Science Forum ◽

10.4028/www.scientific.net/msf.899.311 ◽

2017 ◽

Vol 899 ◽

pp. 311-316 ◽

Cited By ~ 2

Author(s):

F.L. Catto ◽

A.H.G. Gabriel ◽

C. Bolfarini ◽

Claudio Shyinti Kiminami ◽

Conrado Ramos Moreira Afonso

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Laser Cladding ◽

Vickers Microhardness ◽

Steel Substrate ◽

Spray Forming ◽

Glassy Matrix ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Mold Casting

Glassy overspray powders of Ni59Nb35Sn6 (at%) bulk metallic glass (BMG) obtained by spray forming were used in order to produce coatings on AISI 1020 mild steel substrate by laser cladding of the pre-placed powders. Different laser parameters, resulting in a variation of the power density, PD (J/mm2), were tested with a Yb fiber laser (up to 500 W). Gas atomized powders, suction cast sample trough copper mold casting and the laser clad tracks were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and coatings were subjected to measurements of Vickers microhardness. Atomized powder obtained showed no crystalline phases formation up to 425 μm, indicating good glass forming ability (GFA) of Ni59Nb35Sn6 (at%) alloy. Microstructure characterization confirmed maximum glassy dimension of tc =1mm for the Ni59Nb35Sn6 (at%). Laser cladding track showed nanocrystalline phases embedded in a glassy matrix with Vickers microhardness ranging from 336 to 1184 HV.

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The Effect of Forming Speed on the Formability of a Zr-Based Bulk Metallic Glass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1088.265 ◽

2015 ◽

Vol 1088 ◽

pp. 265-271 ◽

Cited By ~ 1

Author(s):

Wu Xiao ◽

Jian Jun Li ◽

Zhi Zhen Zheng ◽

Jin Yang Li

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Wall Thickness ◽

Supercooled Liquid ◽

Supercooled Liquid Region ◽

Outer Diameter ◽

Liquid Region ◽

Forming Process ◽

Element Analysis ◽

Extrusion Forming

Taking cup-shaped part (outer diameter D and wall thickness are chosen as 2.2 mm and 0.05 mm, respectively) as an example, the micro-back-extrusion forming process of a Zr55Cu30 Al10Ni5 bulk metallic glass (BMG) in its supercooled liquid region was studied by using finite-element analysis (FEM) and experiment. The effect of forming speed on the formability was analyzed based on the extrusion load, the rheological behavior of the material and the microstructure of the formed parts. It was found that while the forming speed is below than 4 μm/s, the extrusion load increases obviously with the increasing in forming speed, otherwise, the BMG will follow non-newtonian flow and the forming load is insensitive to the forming speed. The parts fabricated at 2 μm/s are obviously crystallized due to the long retention time of metallic glasses at high temperature, a higher forming speed is benefit to enhancing the formability if the BMG. On this basis, micro cup-shaped parts with only 0.05 mm in wall thickness are successfully extruded.

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