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In hardfacing of automobile engine valves made of heat resisting steel such as 21-4N, conventional oxy-acetylene gas welding has been currently conducted manually by well trained operators because of using cast Stellite rods as the filler. In accordance with the strong demands of automatic welding, we newly developed an automatically controlled Plasma Powder Welding (PPW) system. This system is characterized by the application of a high thermal density plasma arc as heat source and by using powder filler which melts more easily than bar cast rods. Moreover, this PPW system has been applied to the automotive engine valve production line and resulted in the great contribution to manpower saving.

From the viewpoint of reducing the environmental impacts by automobile emission, improving fuel efficiency is essential. That is why automobiles need to be lightened. However, more and more electrical systems have been necessary in an automobile to ensure safety and comfort. With the increase in the number of electrical systems, the weight of Electrical Distribution System (EDS) also has become increased. In order to reduce the weight of EDS, it was decided to evaluate a change of material from copper to aluminum. In fact, aluminum wires have been used for high-voltage wires, but they have almost never been used for low-voltage wires. SUMITOMO ELECTRIC GROUP developed an aluminum wire that is available for low-voltage wire harnesses and started mass production of the wire from October 2010. In this paper, I'm reporting mainly on our development of a new aluminum alloy that can be used for aluminum wires.

The weight of wire harnesses increases with the growing number of systems used in the vehicle in recent years. For the purpose of reducing the weight of wire harnesses, aluminum instead of the conventional copper is getting popular as a wire conductor. The conventional Al wire, however, is not able to be used for small gauge wires such as the sizes of 0.35mm2 and 0.5mm2 and wires used in the engine compartment due to its insufficient conductor strength. For this reason, we tried to develop a stronger aluminum alloy that has conductor strength equivalent to or stronger than that of copper. For the first time in the industry, we have successfully developed a high-strength aluminum alloy wire. Starting with the application of 0.35mm2 wire for engine wire harnesses, we began mass production in April 2015. This paper reports the development of high-strength aluminum alloy that can be used for small gauge wires and wires used in the engine compartment.

We have developed a lead-free, free-machining 0.1 - 0.8% C steel for machine structural use, which demonstrates machinability almost equivalent to lead-containing free-machining steels. This free-machining steel is characterized by controlling the sulfide shape by Ca-Al deoxidation, and, unlike conventional Ca-deoxidized steels (1) and Al-deoxidized CaS free-machining steels (2), its machinability is improved with the aid of manganese-calcium sulphides which precipitate wrapping calcium-aluminate oxides. In order that these duplex inclusions generate, it is essential that the activity balance between [O] and [S] be controlled to 15 ≦ aS/aO ≦ 100. The free-machining steel which satisfies this activity balance has an outstanding machinability and fatigue strength, which are equivalent to lead containing steels. It has been under consideration to apply this novel free-machining steel to automotive parts such as crank shafts and connecting rods.

We developed a remote control unit (Hereinafter referred to as the controller) employing mainly an eight-directional joystick with push-button function. And it has good operational feeling. As previous joysticks generated operator feeling via springs, so the click sensation could not be felt. We thought that a good click feeling can be obtained by applying rubber contacts to the switch element of the joystick. Additionally, in order to include the push-button functions, we supported the operant unit with biaxial bearing and employed a sliding-knob structure penetrating this operant unit. Also in order to obtain a uniform operator feeling for all eight directions, we applied eight rubber contacts and gave the switches eight contacts. In order to restrain the rise in IC costs with the increase to eight contacts, we introduced an eight-contact four- output switch matrix and a one-contact three-electrode pattern.

With the rapid advances in electronic control within automobiles, the junction block (J/B), primarily used for electrical transmission and electrical wiring, has begun to house electronic control units. It is evolving into an active component with smart functions that also controls vehicle devices, at the core of the wiring harness. We have developed a method using CAE to predict the fatigue failure life of J/B brackets for use as a design-assist tool in the early stage of J/B development. Failure of J/B brackets starts with the repetitive stress generated in the brackets during resonance. This stress is maximum at primary natural vibration which is the lowest frequency during resonance. By accurately estimating the above-mentioned stresses using CAE, we established a method to determine the number of vibrations at which fatigue failure of the J/B bracket would occur (fatigue failure life) from the fatigue failure life characteristics of the material.

Fiber-optic data links have been developed for use in vehicle navigation systems, especially for the communication of CD data. The links consist of transmitters, receivers, and cable assemblies. The transmitters, which include only LEDs, must have driver circuits on their exteriors. In the receiver section, a PD, an amplifier, and a TTL compatible comparator are all integrated into the custom designed IC which is hermetically sealed into an originally developed metal package. Small optical connectors and heat-resistant plastic fiber cords with sufficient reliability and good operability for automotive uses have also been developed.

ABS sensor rings for automotive use are becoming smaller and thinner because of the demand for low cost and light weight. Such small thin parts are easier to break as they must withstand the same severe conditions as larger heavier parts. Superior elongation properties, after corrosion testing, are necessary for avoiding breakage and to obtain superior corrosion resistance. We have, therefore, developed such high performance P/M stainless steel with superior elongation and corrosion resistance. Conventional stainless steel has uniform pores on its inner surface which makes allows water penetration thus making corrosion worse and decreasing elongation. It is possible to increase corrosion resistance by changing pore structure (e.g. decrease continual pores) through the addition of special alloys that accelerate the sintering process.

The paper deals with the end-milling machinability of α-β titanium alloy (Ti-6AI-4V alloy) by new PCD (Polycrystal-line Diamond) cutting tools at high cutting speeds in order to develop a new technology for a high productivity titanium finishing. The main focus of this paper is on investigating the relationships among cutting conditions, PCD tool materials, and tool wear. It was found that the edge engagement time of cutting tools with titanium workpiece has a great effect on PCD tool wear. Compared to cemented carbide tools, PCD tools have a longer tool life, especially at higher cutting speeds. The geometric shape of cutting edges and tool material greatly influences the performance of PCD tools in cutting titanium alloy.

The joining process of silicon nitride (S13N4) turbine rotor and steel metal shaft was investigated. The process consists of brazing procedures with multi-layer metallizing and complementary steps involving shrink fitting and non-destructive tests. In the course of the brazing steps, preliminary investigations using small specimens were conducted on the formation of a highly strengthened interface at high temperature and thermal stress reduction, and superior high temperature strength and heat cycle resistance were obtained. Rotary tests at high temperature were successfully completed using the rotor joined by this process.

An internal gear-type pump has advantages compared with an external involute gear-type pump, for example, higher mechanical or volumetric efficiency, considerable reduction of weight and dimension in the oil-pump system[1]. This paper presents characteristics of the internal gear type rotors with a modified trochoidal profile in the oil-pump system, and new P/M(Powder Metallurgy) aluminum alloys which satisfy required wear properties as the lubrication oil-pump rotors. Also, the advantage of high volumetric efficiency and discharge performance and excellent properties of the oil-pump rotor with a modified trochoid profile were combined with a R/S (Rapidly Solidified) aluminum alloy in the scavenging pump for racing car engine. Good results without wear or damage after an actual race are also reported.

A lately established melting-refining-casting process for special steel and their qualities are described in this paper. The process consists of electric arc furnace melting, ladle furnace refining, vacuum degassing and continuous casting in this order. Such a complicated process has been put in the practice for the first time to manufacture particularly automobile steels. One of the advantages of this process is the reduction of impurities such as oxygen and sulfur Oxygen is evacuated during vacuum degassing treatment and sulfur is controlled through ladle furnace refining. As a consequence, cold formability is improved significantly. Mechanical reliability can be increased as well, and especially, it should be noteworthy that stress corrosion cracking of high strength fastners is able to be prevented by the reduction of sulfur. Consistent quality is an another major advantage of the process.

We have developed new P/M Al-Si wrought alloys having high strength and high wear resistance for use in the rotors and vanes of rotary car air conditioners. In addition, combined with the development of near-net-shape extrusion technologies, through a joint project with Diesel Kiki Co.,Ltd., we have succeeded in the world's first mass production of rotors made of P/M aluminum wrought alloy. In this paper, the properties and production technology of vanes and rotors made with new P/M Al-Si wrought alloys are presented.

Recently, SiCr clean steel wire for springs on automotive engine valves has been developed. This report describes the characteristics of valve springs subjected to a new manufacturing process using SiCr clean steel wire. The process developed by the authors is as follows: First, form a helical spring with SiCr clean steel wire. Next, quench using the distortion preventing technic --Marquenching--. Temper at a temperature lower than the conventional temperature. Shot peen to the surface layer of the spring. And lastly, polish electrolytically to remove micro surface defects formed through shot peening. Using this new manufacturing process, a valve spring with high fatigue resistance can be produced. At the test stress of 588MPa(τm)±490MPa (τa), the number of cycles to fracture was above 100 million, while the number of cycles to fracture was 4 million using the conventional process with the SiCr clean steel which has the best fatigue resistance for commercial use.