Bulk Metallic Glass, BMG, the most innovative among the Advanced Materials

The most innovative material with the utmost power. Bulk Metallic Glass, also commonly called BMG (or glassy metal), represents the ongoing revolution of non-crystalline solid materials and advanced materials in general. Its high strength and hardness, combined with a surprising elasticity make it the protagonist of industrial innovation.
Today, BMG is accessible to everyone, with its unique physical and mechanical characteristics.
Join the pioneering revolution of the most advanced materials, let your company grow towards new frontiers, make and experience the future.

What is Bulk Metallic Glass

The term Bulk Metallic Glass defines a new class of solid non-crystalline materials, including amorphous metals.
BMG alloys based on Zirconium and Copper (BMGs are also developed with Titanium, Iron or Platinum) present a glass-like atomic structure, irregular, very strong and elastic.

BMG alloys are scientifically defined as amorphous alloys presenting a glass transition, from which derive their extraordinary properties, including extreme strength at low temperature and high flexibility at high temperature.


The study and use of BMG has already found wide use in the military sector and in space research, but it is very likely that it will soon replace conventional engineering materials in many applications. Furthermore, its application has already been certified in the medical, electronic and sports fields and even in the jewelry sector.

For example, bulk metallic glasses were the object of a study at Lehigh University, as a biomaterial for implantation into bones as screws, pins or plates in order to fix fractures. Unlike traditional steel or titanium, this material dissolves in organisms at a rate of roughly 1 millimeter per month and is replaced with bone tissue.

In the sports field, the BMG has already been tested in the production of golf clubs, as part of the frame of tennis rackets, while in the technological field we find it in the casing of some smartphones, in the gears of some engines (and above all it has already been tested in robots by NASA, to plan the operations on very cold planets, such as the Moon of Jupiter, Europe), in lead-free soldering vessels and in many other areas.
BMG can represent the keystone and the solution to numerous problems for many types of companies, the to innovate their production.


This material can offer:
• High resistance to yield
• The elasticity of plastic
• Corrosion resistance like precious metals - Biocompatibility according to ISO 10993-5
• The hardness of a hardened steel
• A density of 6.0

As a material, it guarantees the possibility of:
• be injected into a mold as a finished piece, with a production time reduced by 70% compared to MIM metallurgy (Metal Injection Molding),
• hot stamp, it can adapt perfectly to the desired shape

BMG’s structure

As an amorphous material, it does not present the typical defects of a crystalline structure, such as dislocations.

Compared to the most common crystalline alloys, the BMG can offer a greater resistance (four times than the others), decreasing the stiffness and demonstrating a high resilience, that is the ability of a material to absorb energy when deformed elastically, and release that energy upon unloading.

A test that can describe this ability is certainly the sequent. If you let some spheres of high hardness fall on a piece of stainless metal or on one of metal glass you will notice a different result: those that have fallen on the BMG will bounce more harmoniously and for a longer duration.
This is because the stainless metal, unlike the BMG, has a lower resistance, is deformed plastically and consequently quickly dampens the kinetic energy of the sphere.

Another characteristic of BMG is that the glass transition temperature is the same than the traditional glass, so that, as it is possible to control the viscosity of the glass it is also for BMG. This makes possible to process or model the material between 280 ° C. and 320 ° C.

- Complete finish in one "Step"
- Constant elastic properties over time
- High yield strength (1500 MPa)
- During molding, tight tolerances as for CNC (see below) - Very high polishing with high reflectivity
- High hardness (HRc 53)
- Corrosion resistance
- Bio Compatibility
- Machine tool workable

Tolerances in production Injection Molding
BMG ± 8 μm CNC ± 8 μm MIM ± 75 - 125 μm

BMG - Liste - Alloys

Vit 1b






Vit 601






Vit 105






Vit 106a











Si0,30% B0,60%












Properties - Alloys



Vit 1b

Vit 601

Vit 105

Vit 106a

Yield strenght

MPa ( ksi )

1800 (261)

1795 (260)

1850 (268)

1800 (261)

Elastic modulus

GPa (106 psi)

95 (13.8)

91 (13.3)

95 (13.8)

Fracture Toughness

MPa √m (ksi √in)

55 (50.0)

70 (63.7)

75 (68.3)

30 (27.3)


g/cc (lbs./in3)

6.0 (0.217)

6.9 (0.249)

6.6 (0.238)

6.7 (242)

Glass transition ( Tg )

C (F)

352 (665)

420 (788)

403 (757)

395 (743)

Crystallization ( Tx )

C (F)

466 (871)

495 (923)

469 (876)

499 (930)

Mel temp ( Tm )

C (F)

644 (1191)

753 (1387)

805 (1481)

837 (1539)

History of the Bulk Metallic Glass

The first Bulk Metallic Glass that can be found in history was an alloy produced in Caltech by W. Klement (Jr.), Willens and Duwez in 1960. The high cooling speed of the process, however, led to the defect of a reduced range of forms in which BMGs could be produced and very limited thickness (the samples had thicknesses less than one hundred micrometers).

The research went on and in 1976 H. Liebermann and C. Graham developed a new method for making thin strips of amorphous metal with an alloy of iron, nickel, phosphorus and boron, whose name was Metglas.
At the beginning of the 1980s, glassy ingots with a diameter of 5 mm were produced from the alloy of 55% palladium, 22.5% lead and 22.5% antimony.

Between 1988 and 1992, other studies discovered multiple glass alloys with a glass transition and a supercooled liquid region. From these studies, loose glass alloys of La, Mg and Zr were made and these alloys showed plasticity even when their web thickness was increased from 20 μm to 50 μm. Plasticity was a clear difference compared to the amorphous metals of the past that became brittle at those thicknesses.

In the 90s of the last century new alloys were developed capable of forming glass at cooling rates equal to one kelvin per second. These "loose" amorphous alloys can be melted in parts of a thickness up to several centimeters (the maximum thickness can vary according to the alloy) maintaining an amorphous structure. The best alloys for the formation of glass are based on zirconium and palladium.

Many amorphous alloys are formed by exploiting a phenomenon called the "confusion" effect: after cooling at sufficiently high speeds, the atoms cannot coordinate in the crystalline state of equilibrium before their mobility is interrupted. In this way we intervene to block the random disordered state of the atoms, obtaining different properties.

In 1992, the amorphous commercial alloy, Vitreloy 1 was developed at Caltech, as part of NASA's Department of Energy and Research for new aerospace materials.

In 2018, a team from the SLAC National Accelerator Laboratory, the National Institute of Standards and Technology (NIST) and Northwestern University reported on the use of artificial intelligence to predict and evaluate samples of 20,000 different metallic glass alloys in a year. Their methods promise to accelerate research and time to market for new amorphous metal alloys.

Who we are

bulkmetallicglass.it is a project by RS Alloys, a company born in February 1997, from an idea of Antonio Bandelli, expert of steel and metals, entrepreneur and communicator divulging innovative and definitive solutions to problems of wear, toughness, bonding and thermal conductivity.
Thanks to the experience, research, passion and willingness to always find new solutions, Rs Alloys has managed over time to respond positively to even very complex problems.

Our vocation is to dialogue with workshops and with an increasing number of companies and industries to solve daily production problems, supporting innovation and cutting-edge with the BMG project. The bulk metallic glass is for us a new challenge, which brings the whole company team towards new goals, in contact with different realities, ready to meet different needs and find answers to contemporary questions.

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