Amorphous Metal (AM) Technology
Introduction
Amorphous metals, also known as metallic glasses, are unique materials characterized by their lack of a long-range ordered crystalline structure. Unlike conventional metals, which have a well-defined, repeating atomic arrangement, amorphous metals have a disordered atomic structure. This lack of crystallinity imparts several remarkable properties to amorphous metals:
Unique Physical Properties
Frozen metallic liquids
Absence of defects
Linear shrinkage during soliddiffication
Unique Physical Properties
High tensile strength up to 1700 MPs
Ultra low roughness 0.1Ra*
Low shrinkage rate
⭢ High forming accuracy ±0.1%
Excellent biocompatibility
Outstanding environmental resistance
Currently, we have two different methods for forming amorphous metals (AM), including injection molding and 3D printing. Injection molding has excellent mass production capabilities for producing standardized products. 3D printing, on the other hand, has the ability to form complex workpieces and is not limited by the glass-forming ability (GFA), allowing for the creation of larger metallic glass components.
IMTEC - AM Injection Molding
Mass - produced product
AMTEC - AM 3D Printing
Customized, complex products
Case Study: Benefits of Amorphous Metal for Watch Cases
The significant advantages of using amorphous metal for watch cases, including improved hardness, smoothness, precision, and corrosion resistance. It also shows a comparative analysis of the production process, indicating that amorphous metal not only provides superior properties but also offers a faster manufacturing process compared to traditional MIM with 316L stainless steel, albeit at a slightly higher cost.
Watch Case: Volume: 3.205 cm³
Special “rapid freezing“ process creates amorphous structure.
Scratch resistance - hardness of up to 500VH, 3.8 times that of 316L.
High smoothness - surface roughness of Ra 0.05µm, reducing polishing by 80%.
High precision - shrinkage ~ 0.25%, reducing post-processing by 90%.
Corrosion resistance - withstands salt bath for over 30 days and salt spray for over 600 hours.
Flexural Strength Performance
Amorphous metals exhibit exceptional mechanical strength due to the absence of grain boundaries and crystalline defects, which are typically the weak points in traditional metals. It also has a high elastic limit, meaning they can undergo significant deformation and return to their original shape without permanent deformation.
| INNOJET Amorphous Metal | 300M / 434M | Ti-6AI-4V | |
|---|---|---|---|
| Density (g/cm³) | 6.65 | 7.87 | 4.43 |
| Specific Strength (MPa) / (g/cm³) | 256 | 245 | 237 |
| UTS (MPa) | 1700 | 1930 | 1050 |
| Yield Strength (MPa) | 1600 | 1634 | 935 |
| Young's modulus (GPa) | 89 | 205 | 113.8 |
| Fatigue-endurance limit @ 10⁷ cycles (MPa) | 425 | 428 | 283 |
| Vickers hadness | 540 | 567 | 349> |
| Thermal Conductivity (w/mk) | 2.5 | 37.5 | 6.7> |
| Corrosion Resistance | Superior | Bad | Good> |
With higher elasticity and dimensional stability can withstand even higher loads and, due to the high strength, does not even break at loads where the compared crystalline materials are already plastically deformed and buckled away.