Application And Research Of Modified Nano-SiC Powders Reinforced Technology On The Cast Duplex Stainless Steel

Abstract Duplex stainless steel (DSS) has excellent corrosion resistance and mechanical properties, is a truly high-performance structural materials are being increasingly used in chemical, petrochemical, paper and oil industries. In order to further improve the performance of duplex stainless steel and expand application, this study basic on the experimental studies, used the advanced strengthening and toughening of modified nano-SiC powders technology to cast duplex stainless steel, the successful preparation of the modified nano-SiC powders enhanced duplex stainless steel materials.The nano-SiC powders are surface modified before using, particle size of 20-80nm. Using transmission electron microscopy study of the modified nano-SiC powder composition and morphology, through metallographic examination, Brinell hardness testing, tensile testing, impact testing, scanning electron microscopy, chemical immersion test, electrochemical analysis methods such as detected a duplex stainless steel of grain size, mechanical properties, fracture morphology and corrosion resistance, and further discussed the effection and theory of different weight nano-SiC powders add into duplex stainless steel reforming mictructure, mechanical properties and corrosion resistance.The results show: Adding modified nano-SiC powders into the duplex stainless steel, which could be significantly enhanced, mictructure refinement, mechanical properties, pitting corrosion and uniform corrosion resistance were evenly effectively improved. When adding the nano-SiC powder content of 0.1%, the strengthening effect was most apparent elongation and cross-section shrinkage rate increased by 3.76% and 3.82%, hardness, tensile strength and toughness were increased by 6.11%, 7.18% and 13.6 %; Fracture analysis showed: With the strengthening and toughening treatment, the duplex stainless steel fracture surface of the dimples on a marked increase in quantity; Polarization curves show: reinforced duplex stainless steel electrode potential is improved, when the content of nano-SiC powder is 0.1%, the duplex stainless steel electrode potential increased-0.08V.The SiC powders could as the base core when it was added into the casting, the SiC is finer, the capability of form crystallization core is bigger, increasing the strengthening and toughening are better, so the surface modified nano-SiC powders could be widely applied in the casting production.