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Weight reduction for a fuel cell vehicle (FCV) is important to contribute a long driving range. One approach to reduce vehicle weight involves using a carbon fiber reinforced plastic (CFRP) which has a high specific strength and stiffness. However, a conventional thermoset CFRP requires a long chemical reaction time and it is not easy to introduce into mass production vehicles. In this study, a new compression-moldable thermoplastic CFRP material for mass production body structural parts was developed and applied to the stack frame of the Toyota Mirai.

Recently the demands on automobile engines have greatly increased, these demands include better performance and improved energy efficiency and more environmentally friendly materials. As a result of these demands, the requirements on valve guides in the valve train have increased, not only in regards to greater wear resistance but also in regards to better machinability. In particular, the valve guide tool is now expected to have a longer life, a shorter machining time and a reduction in the revolving energy of the tool. We, at Hitachi Powdered Metals, in order to answer to these new requirements have improved the machinability sintering valve guide material where, up until now, it has been difficult to improve the machinability and the wear resistance at the same time.

The demands on valve seat inserts are that they should have enhanced wear resistance and machinability using non-environmentally hazardous materials at a reasonably low cost. Research into the possibility of producing a new valve seat insert material which fulfills such demands was therefore made. As a result Hitachi Powdered Metals (HPM) has developed a new material which uses dispersed die steel hard particles in the production of intake valve seat inserts.

The Vapor Reducing Fuel Tank System (Bladder Tank System) using a flexible plastic membrane (Bladder Membrane) was newly developed in order to reduce the amount of vaporized gasoline in a steel fuel tank. This Bladder Membrane is flexible to expand in proportion to a fuel volume and prevents the permeation of the vaporized gasoline. As a result of our initial study for various materials, we decided to apply a multi-layer plastic material which could achieve both low fuel permeability and good flexibility. This multi-layer material consists of polyethylene(PE) for structural material and polyamide(PA) for low permeability. The modulus of the PE needs to achieve a sufficient flexibility in order to keep the movement of the membrane. While PA material must have not only low fuel permeability but also strong adhesion with the structural material of PE. We also clarify the membrane design to keep a good flexibility and to reduce a strain.

The demands on valve seat insert materials, in terms of providing greater wear-resistance at higher temperatures, enhanced machinability and using non-environmentally hazardous materials at a reasonably low cost have intensified in recent years. Due therefore to these strong demands in the market, research was made into the possibility of producing a new valve seat insert material. As a result a high speed steel based new improved material was developed, which satisfies the necessary required demands and the evaluation trials, using actual gasoline engine endurance tests, were found to be very successful.