Thermoplastic forming of additively manufactured Zr-based bulk metallic glass: A processing route for surface finishing of complex structures

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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Thermoplastic forming of bulk metallic glass—Applications for MEMS and microstructure fabrication

Materials Science and Engineering A ◽

10.1016/j.msea.2006.02.398 ◽

2007 ◽

Vol 449-451 ◽

pp. 898-902 ◽

Cited By ~ 94

Author(s):

Jan Schroers ◽

Tranquoc Nguyen ◽

Sean O’Keeffe ◽

Amish Desai

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Microstructure Fabrication ◽

Thermoplastic Forming

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Thermoplastic Forming Properties and Microreplication Ability of a Magnesium-Based Bulk Metallic Glass

Advanced Engineering Materials ◽

10.1002/adem.200800104 ◽

2008 ◽

Vol 10 (11) ◽

pp. 1048-1052 ◽

Cited By ~ 6

Author(s):

J. S.-C. Jang ◽

C.-T. Tseng ◽

L.-J. Chang ◽

J. C.-C. Huang ◽

Y.-C. Yeh ◽

...

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Thermoplastic Forming

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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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A thermoplastic forming map of a Zr-based bulk metallic glass

Acta Materialia ◽

10.1016/j.actamat.2012.12.013 ◽

2013 ◽

Vol 61 (6) ◽

pp. 1921-1931 ◽

Cited By ~ 56

Author(s):

N. Li ◽

Y. Chen ◽

M.Q. Jiang ◽

D.J. Li ◽

J.J. He ◽

...

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Thermoplastic Forming

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The Redistribution and Alignment of Crystalline Flakes in a Bulk Metallic Glass Composite during Thermoplastic Forming

Materials Science Forum ◽

10.4028/www.scientific.net/msf.702-703.971 ◽

2011 ◽

Vol 702-703 ◽

pp. 971-974

Author(s):

Wan Qiang Xu ◽

Lalu Robin ◽

Kevin J. Laws ◽

Rong Kun Zheng ◽

Michael Ferry

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Amorphous Matrix ◽

Volume Fraction ◽

Supercooled Liquid ◽

Glass Composite ◽

Uniform Dispersion ◽

Thermoplastic Forming ◽

Bulk Metallic Glass Composite

An In-situ Mg-based bulk metallic glass (BMG) composite containing 40% volume fraction of Mg-rich crystalline flakes was produced by die casting. During cooling from the melt, the flakes nucleate heterogeneously and subsequently grow with their broad faces parallel to the {0001} plane. This generated a uniform dispersion of randomly-oriented flakes within an amorphous matrix. When compressed uniaxially up to 60% reduction in the supercooled liquid (SCL) region, the flakes in this composite were substantially aligned their broad faces towards the compression plane that generated a strong //ND fibre texture.

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Thermoplastic Forming of a Hydrophilic Surface with a Nanostructure Array on Zr-Cu-Ni-Al-Y Bulk Metallic Glass

Metals ◽

10.3390/met11101520 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1520

Author(s):

Sirui Cheng ◽

Jiang Ma ◽

Feng Gong ◽

Jun Shen

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Low Cost ◽

Supercooled Liquid ◽

Volume Density ◽

Roughness Coefficient ◽

Limiting Factor ◽

Nanostructure Fabrication ◽

Thermoplastic Forming ◽

Large Roughness

The poor thermoplastic formability of reactive Zr-based bulk metallic glass becomes the main limiting factor for replacing the noble-metal-based and Be-rich bulk metallic glasses in nanostructure fabrication. In our work, a (Zr50.7Cu28Ni9Al12.3)98.5Y1.5 bulk metallic glass with good thermoplastic formability has been developed by alloying, where Y addition enlarges the processing window and decreases the viscous resistance of supercooled liquid caused by the high free volume density. The prepared Zr-Cu-Ni-Al-Y bulk metallic glass nanostructure retains the amorphous characteristic and generates the complex oxidization products in the surface layer. The enhanced hydrophilicity of the as-embossed surface follows a Wenzel-impregnating wetting regime, and it can be attributed to the large roughness coefficient induced by the capillary effect. This study provides a low-cost and environmentally friendly bulk metallic glass system to manufacture the nanostructure with a broad prospect in the field of electrocatalysis.

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