新型节镍2304双相不锈钢无缝管的热穿孔工艺优化OA

Studied here in the article is the hotpiercing process for the new nickel-saving 2304 duplex stainless steel by means of thermodynamic calculations,high temperature plasticity test,microstructural characterization,and industrial trial,etc.Resulting in optimized hotpiercing process parameters.The results demonstrate that a safe hot working range is 1 050℃and 1 150℃,within which the microstructure primarily consists of austenite and ferrite,thereby avoiding the precipitation of brittle phases such as M2(C,N)and M23C6.In the range of 1 050～1 100℃,austenite is the dominant phase,and dynamic re-crystallization leads to excellent hot plasticity.Between 1 120℃and 1 150℃,the ferrite fraction increases,and plasticity is governed by dynamic recovery mechanism.The addition of vanadium promotes the formation of V(C,N)precipitated phase,which refines the grain size,and suppresses nickel diffusion at high temperatures,thus stabilizing the phase ratio and achieving a refined grain size.The shell made via industrial trial production possesses exce-llent surface quality and homogeneous microstructure,meeting all the requirements for downstream processing.