稀土型铁素体不锈钢430组织及韧性研究

以铁素体不锈钢430为研究对象,通过添加0.06%稀土,可改善铁素体不锈钢430的凝固组织,使凝固组织中的柱状晶区域减小,等轴晶区扩大;可改变铁素体不锈钢430中夹杂物的形貌、组分和分布,夹杂物由脆性夹杂改性为塑性夹杂,同时夹杂物的尺寸减少;有利于铁素体不锈钢430热轧板组织的改善,晶粒进一步细化,晶粒度由6级提高到8级;可改变铁素体不锈钢430的冲击断口形貌,断口形貌由脆性解理断口向韧性断口转变。

Microstructure and Ductility of Rare Earth Doping Ferrite Stainless Steels 430

The ferrite stainless steel 430 with adding 0.06% rare earth was studied as a subject,by the solidified microstructure of the ferrite stainless steel 430 was improved,and the area of columnar crystal in the solidified microstructure was reduced and the area of equiaxed crystal was increased.The morphology,composition and distribution of the inclusions in ferrite stainless steel 430 was changed.The characteristic of inclusion was changed from brittle to plastic and the size of inclusion was reduced.Furthermore,the microstructure of ferrite stainless steel 430 hot-rolled plate was also improved,and the grain degree was increased from grade 6 to grade 8.When the grain was further refined,the impact fracture morphology of ferrite stainless steel 430 was changed,and the fracture morphology transformed from brittle cleavage fracture to ductile fracture.