Tanaka Kikinzoku Kogyo obtained a patent for the composition of platinum-based metallic glass in 2004, and with this development, the company became the first in the world to powderize platinum-based metallic glass that can be used in existing selective laser sintering 3D printers by adjusting particle diameter and fluidity through the use of proprietary equipment. Tanaka Kikinzoku Kogyoalso developed two types of powder material using nickel-based alloys with platinum and iridium additives. Joint research was conducted with the Technology Research Institute of Osaka Prefecture, with the revelation of laser energy irradiation conditions optimized for the quality and shape of powder resulting in the successful manufacture of objects made of platinum, platinum-based metallic glass and nickel-based alloy with iridium additive. This marks the world's first formation of platinum-based metallic glass using 3D printers. Tanaka Kikinzoku Kogyo will provide platinum group metallic powder, in addition to processing the diameter size of platinum group metallic powder particles, proposing formation in the manufacture of platinum group alloys, and manufacturing objects depending on requests from customers.
Platinum group metals have a high melting point and are durable, but many — especially alloys — have poor workability such as cutting and plastic forming, and there were limitations in the shapes available using existing forming methods. Enabling these materials to be formed using 3D printers makes it possible to form complex shapes and manufacture complex products using materials with different melting points. This development is expected to lead to small lot production of a diverse range of products requiring corrosion resistance such as medical materials, and the expansion into industrial products with specialized components in areas requiring heat resistance such as the automotive industry and the aerospace industry. Tanaka Kikinzoku Kogyo aims for annual sales of 400 million yen by FY2020 with the provision of platinum group metallic powder materials for 3D printer use.
■ The potential of platinum-based metallic glass
Metallic glass is a type of amorphous metal that does not have a crystalline structure like ordinary metals. It is widely known for its high strength, great hardness, low flexibility, ultra-high corrosion resistance, high magnetic permeability, high molding workability, smooth surface, friction resistance, scratch resistance, precise casting and low vibration damping properties, and is gaining attention as a next-generation material. Tanaka Kikinzoku Kogyo was the first in the industry to develop platinum-based metallic glass using the precious metal platinum, and also to work with palladium-based metallic glass. The company obtained patents for composition using platinum, copper and phosphorus in 2004. It has developed metallic glass and provided test materials including a wide range of precious metals including those with publicly known compositions, and realized the powderization of these as a material for 3D printers with this most recent development.
The most widespread method of manufacturing metallic glass at present is casting, which involves pouring molten metal into a cast and quickly cooling it to harden. Casting requires a cast to be created in advance each time a different shape is being made, but in the manufacture of metallic glass, which requires particularly fast cooling, it is necessary to use an expensive metal cast with high thermal conductivity. However, one issue faced in practical application is the limitation of shapes that can be made due to the difficulty involved in processing these metallic casts to form complex shapes.
This method of manufacturing using a 3D printer and the recently developed platinum group powder material forms objects by using a laser beam to irradiate each layer (approximately 60 micrometers) of powder material from the top, enabling the surface of each layer to cool quickly while being formed. Platinum-based metallic glass is expected to be used in further practical applications in the future due to the ability to use it to form complex shapes.
Tanaka Kikinzoku Kogyo aims to expand the effective uses of precious metals through the development of various platinum group alloy powder material for 3D printers.
Source: Tanaka