Ni and cu free pd-based metallic glasses

Abstract

The invention is directed to Pd-based metallic glass alloys useful in biomedical applications having no Ni or Cu. Exemplary metallic glass alloys are represented by AaBb{(Si)100-c(D)c}d, where A may be selected from Pd, and combinations of Pd and Pt, B may be selected from Ag, Au, Co, Fe, and combinations thereof, and D may be selected from P, Ge, B, S. Also, a, b, c and d are atomic percentages, and a ranges from about 60 to about 90, b ranges from about 2 to about 18, d ranges from about 5 to about 25, and c is greater than 0 and less than 100.

Description

CROSS-REFERENCE TO RELATED APPLICATION(S)[0001]This application claims priority to and the benefit of Provisional Application Ser. No. 60 / 959,296, filed on Jul. 12, 2007 and entitled NI AND CU FREE PD-BASED GLASSES, the entire content of which is incorporated herein by reference.FIELD OF THE INVENTION[0002]The invention is directed to Ni and Cu free Pd-based metallic glasses. More particularly, the invention is directed to Pd-based glass-forming alloys useful in biomedical applications.BACKGROUND OF THE INVENTION[0003]Metallic glasses, unlike conventional crystalline alloys, have amorphous or disordered atomic-scale structures that give rise to unique chemical, mechanical, and rheological properties. Owing to their atomic structure, metallic glasses generally exhibit better corrosion resistance than typical crystalline alloys, higher hardness, strength, and elasticity, and are able to soften and flow when relaxed above their glass transition temperatures (Tg), a characteristic that ...

AI Technical Summary

Benefits of technology

The alloy composition enables the production of biocompatible, high-toughness, and high-strength metallic glasses suitable for biomedical applications, such as orthopedic and orthodontic implants, without the cytotoxic effects of Ni and Cu, and is also applicable in jewelry due to its biocompatibility.

Problems solved by technology

Previously, metallic glasses were only capable of being produced in sub-millimeter dimensions (thin ribbons, sheets, wires, or powders) due to the need for rapid cooling from the liquid state to avoid crystallization.

However, recent developments in bulk glass-forming alloys have enabled the production of metallic systems with very sluggish crystallization kinetics able to form glasses in dimensions as large as several centimeters.

However, due to the prohibitively high cost of Pd (a noble metal) most of these applications remain out of reach.

As such, the inclusion of Ni and Cu is widely accepted as necessary to the formation of glass-forming alloys, and skilled artisans in the field would have no expectation of success in creating a good glass-forming alloy without including at least one of these metals.

While the inclusion of Ni and Cu in metallic glasses is generally suitable and acceptable when the glasses are used for engineering applications, these metals are highly cytotoxic, making metallic glasses including these metals ill suited for biomedical applications.

Such free radicals are notorious triggers for severe adverse biological reactions in the body.

As the glass-forming ability of amorphous metal alloys is strongly dependent on the inclusion of Ni and / or Cu, development of Pd-based metallic glasses suitable for use in biomedical applications has proved extremely challenging, and no suitable such metallic glass has yet been achieved.

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