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This article introduces “wide view wiper system” which will be able to eliminate the deviation of wiping area between low-speed and high-speed. This system will consist of a structure wherein the actual length of motor arm will become longer at low-speed mode and shorter at high-speed mode through switching an eccentric bearing that is built-in with the motor arm. This eccentric bearing will be switched automatically following motor rotation direction when speed mode will be changed. As a result, this wiper system will be able to realize the high wiping rate at low-speed operation mode and the lower park position of wiper arm and blade to improve the vehicle appearance.

Automotive exhaust gas condensate causes severe corrosion inside mufflers. Corrosive condensate became a problem following the introduction of three-way catalytic converters in exhaust systems. The authors previously established a new laboratory test method that simulates condensate corrosion. This test method contributed to the development of new stainless steels for automotive mufflers. The addition of molybdenum (Mo) and copper (Cu) to ferritic stainless steels was found to be effective in improving condensate corrosion resistance, and the effect was arranged using the index [%chromium (Cr)+3×%Mo+1.5×%Cu]. A field test was carried out to investigate the corrosion behavior of mufflers under actual conditions. Aluminized steels showed severe damage by general corrosion. On the other hand, 19%Cr-Cu ferritic stainless steel exhibited excellent corrosion resistance. The corrosion behavior in the field test showed good agreement with the results of the laboratory test.

Exhaust manifolds have been fabricated from stainless steels such as type 409 in place of cast iron in order to reduce the weight and to increase performance of the engine. In this paper, thermal fatigue and high temperature fatigue resistances of Nb-bearing ferritic stainless steels and type 409 have been investigated. The results obtained are as follows: Nb-bearing steels were superior to type 409 in high temperature fatigue resistance. Thermal fatigue resistance depended on a restraint ratio. The fatigue life of Nb-bearing steels was longer than that of type 409 in the condition of a low restraint ratio which might be near to the actual automobile exhaust system.

Metallurgical factors affecting the press formability of the newly developed high strength sheet steels have been discussed. Dual phase steels, CHLY(cold-rolled sheet steel) and HTP-D(as-hot-rolled sheet steel), produced by control of cooling conditions after intercritical annealing or hot-rolling exhibit very low yield to tensile strength ratio and high n-value. Rephosphorized extra-low carbon steel, CHRX, produced by continuous annealing with rapid cooling is characterized by its extremely high r-value and low yield strength. CHLY, HTP-D and CHRX have large bake hardenability. Precipitation hardened steel, HTP-F(hot-rolled sheel steel), produced by adjusting carbon equivalent and sulfur content is suitable for manufacturing wheel rims owing to its good formability after flash butt welding.

Deep drawing quality high strength (400 MPa grade) cold-rolled steel sheet for automotive use has been developed. This steel sheet is characterized by its chemical composition of extra low carbon, high phosphorus and small niobium together with aluminum. It exhibits very high r̄-value and elongation in tensile test and also an excellent deep draw-ability in small cup test and actual press test of automotive panel parts. The resistance to cold-work embrittlement are improved by controlling the compositions and the cooling rate after final annealing. Spot weldability and the weld performances are very good like as ordinary mild steel sheets. These properties are compared with those of DDQ grade mild steel sheet and previously developed high strength dual phase or rephosphorized steel sheets.