The Internet has made it possible for information to be transmitted throughout the world in real time. When it comes to moving people and products however, it's the aircraft industry that has taken the lead in reducing time. Since 1995, air transportation has continued growing at an annual rate of 5% (converted to revenue passenger-kilometers) despite two global economic recessions. It is predicted that Asia will lead the industry's growth over the next 15 years, whilst in Europe the wide variety of commercial airlines servicing almost every airport means that the skies will continue to become ever busier.
A huge variety of aircraft have been developed to meet transport market needs for service between continents, regions and cities; and now, the aircraft industry is revolutionising its products to address global warming and other environmental issues. In addition to increased ratios of light but strong materials, from titanium alloys through to carbon fiber reinforced plastic (CFRP) to reduce weight and lower fuel consumption, the Boeing 787, Airbus A350 and other new passenger jets have adopted new low-noise jet engines to realise significant reductions of environmental load. As for Japan, Mitsubishi Aircraft Corporation's new MRJ passenger jet is gearing up to begin commercial service. Airlines throughout the world are now adding jets to their fleets that are friendly to both passengers and the environment.
Most passenger jets have between 3 and 6 million components and light, strong materials are commonly used for these components. The majority of the structural components are machined and the engines use special alloys that can withstand extreme temperatures and pressures. The need for efficiency, precision and quality makes it essential to have cutting tools specifically designed for each material.
Many of the panels and ribs (structure) of the airframe are made of super duralumin (A7075). High-efficiency processes are essential to machine components from blocks of material. These machining processes can sometimes reduce more than 90% of the solid material into chips to leave the final shape required.
Recently, cutting tools capable of machining components at a speed of 5,000m/min (300km/h) have been commercialised. The chip evacuation rate of these processes can be up to 10,000cm3 per minute.
Titanium alloy has the highest specific strength (strength/weight ratio) of all metallic materials under 400 deg.C, it is also light, strong and corrosion resistant. New passenger jets are using an increasing ratio of Titanium alloy Ti- 6Al-4V, this material is used for aircraft components that require high strength, such as wing joints and landing gear. High efficiency machining of Titanium alloy is a challenge because its low thermal conductivity causes machining heat to concentrate on the edge of the cutting tool.
Ten times stronger than steel (strength/ weight ratio), CFRP is light, strong and corrosion resistant and its use has grown rapidly in the 21st century. Large aircraft components such as fuselage parts are moulded by layering sheets containing carbon fibers in special pre-defined forms and then by heating them in a vacuum. CFRP's high strength however means it has low machinability properties and therefore requires diamond or diamond coated tools for cutting them.
even under severe temperatures of up to 1,000 deg.C. It is used in sections of the engine associated with combustion and exhaust. Nickel based INCONEL® and WASPALOY® are common examples. Superalloys maintain their strength even under high temperatures but these properties also cause low machinability. They also require high quality machining and therefore manufacturing processes need careful examination and planning before mass production is viable.
Mitsubishi Materials Corporation began full scale development of cutting tools for the aircraft industry in 2001. However, the high standard of tools already available in Europe and the US meant a continual development process of aerospace tools to where Mitsubishi Materials Corporation now provides a diverse line of high performance cutters. In addition the Company has a total of 20 aerospace experts stationed in 10 global locations, including Japan, the US, Asia and Europe. With a priority on improving the technology of its products and machining processes, a level has now been reached that allows the Company to participate in joint international development projects for new passenger jets. Two experienced managers from Mitsubishi Materials Corporation are taking part to help contribute Japanese know-how to the advancement of the aircraft business.
Aerospace Business Manager Masaaki Ito approaches machining from a comprehensive perspective, using his 11 years experience at a machining tool manufacturer working with ISO compliant tooling systems for combined machining equipment. The technology developed by his department has been developed by machine tool manufacturers in collaboration with universities and research institutes as well as aircraft manufacturers. Masaaki Ito says, "Our high-efficiency processing technology for difficult-to-cut materials has reached a level that could not be achieved by a machine tool manufacturer alone." Mitsubishi Materials Corporation has strategically promoted the establishment of world partnerships for further expansion of the aircraft business. In line with this, the Company joined the worldclass Advanced Manufacturing Research Centre (AMRC) in the UK in spring 2014. AMRC carries out research on projects from major aircraft manufacturers and has utilised Mitsubishi‘s solid end mills for titanium alloy machining. Currently, the Company is working in close cooperation with specialists placed in domestic and global R & D sections and is combining these efforts into the design of new products that will advance the next generation of machining.
Engineering Manager Tsuyoshi Nagano has been involved in the development of machining technology since he joined the Company some 20 years ago. He has managed in-house development testing and new processing technology development which have led to his achievements being featured at exhibitions throughout the world. After transferring to application engineering his wealth of experience in machining technology helped him establish trusted relationships with aircraft and machine tool manufacturers. He has worked mostly in Asia and Japan with a focus on practical technology support and problem solving for difficult-to-cut materials utilising the Mitsubishi Materials network. He also promotes participation in machining and aerospace exhibitions in North America, Europe, and China as well as in Japan. Mitsubishi Materials was the only cutting tool manufacturer from Japan to participate in the 2014 Zhuhai international aerospace show, the largest in China.