On 28 April 2009, Sumitomo Metal Industries Ltd has received a Contribution Award of the 41st Ichimura Industrial Prize from the New Technology Development Foundation for its development of steel plate for improving the fatigue strength in welded joints, which was titled “Development and commercial application of new functional steel material with an extended fatigue-life.” The company has developed and commercialized “FCA-W steel plate,” high-tensile-strength plate that delays fatigue crack initiation in welded joints. In conventional steel plates, the fatigue strength in welded joints has been a weak point. It has generally been thought that the fatigue strength in welded joints was constant, and that this could not be improved with steel plates, no matter what kind of steel plate was used. For this reason, in order to ensure fatigue strength, other methods have been employed, such as increasing the thickness of plates, attaching reinforcement members to welded joints. In addition to a function to control the propagation of fatigue crack, this steel plate functions to delay the initiation of fatigue cracks in welded joints. By simply replacing conventional steel plates in the steel structures to “FCA-W steel plates,” the structures can have an extended life and a reduction in weight, without increasing the thickness of plates and attaching reinforcement members. The application of “FCA-W steel plate” in automobile chassis, construction machinery, and railway bogie trucks has been under study. Sumitomo Metals has also received requests for its application in offshore structures, wind power generation equipment, and mining machines.
