| Biography | |
|---|---|
 Prof. Hitoshi Soyama Tohoku University, Japan |
|
| Title: Improvement of Fatigue Strength of Light Metals by Mechanical Surface Treatment | |
| Abstract: Light metals such as aluminum alloy, magnesium alloy and titanium alloy are attractive materials for automotive lightweight and aviation components. However, one of weak points is the fatigue strength. One of key technologies for enhancement of fatigue strength is mechanical surface treatments such as shot peening. Unfortunately, it is difficult to improve the fatigue strength of the light metals by conventional shot peening, as solid collision by shot increases surface roughness of because of the softness of the light metals. In the present invited speech, a novel peening method without shot, i.e., shotless peening, will be introduced. In the proposed shotless peening, cavitation impacts, which are normally causes severe damage in hydraulic machineries such as pumps, ship propellers and valves, are used to create local plastic deformations. This peening method is named as “cavitation shotless peening” or simply called as “cavitation peening”. In the speech, the fundamental and the practical application of cavitation peening are introduced with experimental data. The improvement of fatigue strength of additive manufactured titanium alloy Ti6Al4V is also demonstrated comparing with shot peening and laser peening. | |
| Biography: Hitoshi Soyama has completed his PhD from Tohoku University, Japan. He has been working at Tohoku University since 1991, and he was promoted to a professor at 2003. He was awarded as a Fellow of American Society of Mechanical Engineers ASME and a Fellow of Japanese Society of Mechanical Engineers JSME. He is also an honorary member of Water Jet Technology Society of Japan. He is known for his work in the fields of mechanical surface treatment, especially cavitation peening in which cavitation impacts utilized to improve fatigue strength of metallic materials such as aluminum alloy, magnesium alloy, titanium alloy and steels. | |
