The chromized layer formed on the surface of Q195 steel using glow plasma alloying technique to improve the crossion resistance of Q195 steel.The structures,depth,phase composition and surface chromium content of chromized layer at different pressure were analyzed by metalloscope XRD and SEM.The optimize parameters were confirmed.The corrosion resistance of optimize chromized layer in 3.5 % NaCl solution and 1 mol/L NaOH solution are investigated by electrochemical corrosion.The results show that the alloying layers are 30 μm,50 μm and 100 μm in depth and the surface chromium content are 9.25 %、16.63 %、13.82 %(wt %) respectively when the pressures are 25 Pa,35 Pa,45 Pa.The chromized layers are dense and combining closely with the substrate.The depth of the alloying layer increases with the pressure increasing.In a certain rang,the surface chromium content increases with the pressure increasing.Once over a certain value,the surface chromium content decreases with the pressure increasing.Compared with untreated Q195 steel,the corrosion resistance of chromized layer increases 10 times in 3.5 % NaCl solution and 5.13 times in 1 mol/L NaOH solution.
