레이저 피닝에 의한 2205 듀플렉스 스테인리스강의 표면 경도 향상과 표면변화 관찰

Abstract

This work reports the results for laser shock peening of duplex stainless steel (22o/o Chromium - 5% Nickel) using a pulsed Nd:YAG laser (wavelength : 532nm+ pulse width : Sns). for the application to high-capacity pumps for seawater desalination plants. By properly selecting the process parameters such as laser intensity of lOGWcm2, laser pulse density of T5pulse/rnm2, and l00pm thick aluminum foil as an absorbent coating layer, the swface hardness of duplex stainless steel could be enhanced by 260/o, from 2561 1 to 323tIV with little changes in surface moqphology and roughness. The depth of laser shock peened layer was measured to be around 2mm. The large enhancement of surface hardness is considered to have high practical importance in minimizing abrasive and corrosive deterioration of pump parts.