冷轧硬化对超级双相不锈钢S32750析出相的影响

 为了优化不同厚度冷轧板加热工艺，避免有害相析出，研究了冷硬化对S32750板材析出相的影响。超级双相不锈钢S32750钢板经不同冷轧加工变形后，在850 ℃下进行热处理。利用SEM、EDS、XRD及TEM研究了不同冷轧总压下率对析出相的影响规律。结果表明，随着总压下率的增大，相同退火时间内，析出相增多，当总压下率大于50%时铁素体相几乎全部被析出相覆盖。析出相以σ相为主，伴随着很少量的Cr2N、χ相和γ2。σ相和χ相析出在α/γ相界和铁素体相内，Cr2N析出在α/γ相界处，γ2伴随着σ相析出在铁素体内。随着冷轧总压下率增加，晶体内的位错密度增大，析出数量增加。

Influence of cold rolling on precipitation of S32750 super duplex stainless steel

 To optimize heating process and avoid precipitating harmful phase within cold plates，the effect of cold hardening on precipitation of S32750 plate was studied. Super duplex stainless steel S32750 plates were heated at 850 ℃ after different cold deformation. The precipitations were studied by SEM，EDS，XRD and TEM. The result shows that the amounts of precipitation increases with the cold deformation increasing，when the cold deformation rate bigger than 50%，the ferrite phase almost filled with precipitation. The precipitations almost are sigma phase，except for small amount Cr2N，χ phase and γ2. σ and χ phase were precipitated at the phase boundary and ferrite phase，Cr2N is precipitated at the phase boundary and secondary austenite in the ferrite with the Sigma phase. The dislocation density increases with the cold deformation increasing，which lead to the precipitation speeding up.