18%Cr鋼および25%Cr鋼の熱間押し出し加工時の不均一変形

抄録

Mechanism of stringy defect formation on hot extrusion of high chromium steels and its prevention methods were investigated.
It was estimated that stringy defect resulted from the strain in circumferential direction relatively larger than in extrusion direction.
Stringy defect can be prevented by refining the structure, i.e. promoting the precipitation of austenite or adding a carbide/nitride former element.