简介：Anexperimentalstudyandcomputersimulationonnon-equilibriumgrain-boundarysegregationkineticsandthecriticaltimeforphosphorusin12Cr1MoVsteel(whichisusedinsteampipelineofships)areputforwardinthispaper.Thesegregationlevelofphosphoruswithsolutiontemperature1050℃attheisothermalholdingtemperatureof540℃,havebeenmeasuredatgrain-boundaries.Anon-equilibriumgrain-boundarysegregationkineticscurveofphosphorusisgiven.Thecriticaltimeforphosphorusnon-equilibriumgrain-boundarysegregationisabout500hat540℃fortheexperimentalsteel.Whentheholdingtimeislongerthan1500h,non-equilibriumsegregationdisappearsandthelevelofsegregationreachesfullequilibrium.Thesimulationusingthekineticequationsofnon-equilibriumgrain-boundarysegregationisingoodaccordancewiththeexperimentalobservationforphosphorusinsteel12Cr1MoV.Thenon-equilibriumgrain-boundarysegregationkineticmodelisthereforeproved.