Effect of Cooling Condition on Deformation of Continuously Cast Stainless Steel 304

- Dec 12, 2016-

Stainless steels are used in parts requiring corrosion resistance, high resistance to temperature, and formability. In addition, 100% recyclable and aesthetic appealing stainless steel has been a preferred choice of material for architects. Alterations in chemical or thermal process to the base stainless steel (Fe-Cr-Ni) can modify the microstructure and properties of the stainless steel family of alloys. Thus different numbers, which are selected depending on specific applications, are assigned to various stainless steels. The components made with stainless steel, for example, are automobile exhaustive systems (409), body frames (duplex), medical/biomaterials (316), nuclear plants (309, 316), chemical plants (304, 316), as well as household utensils (304, 430). Stainless steel 304 is austenitic with relatively high chromium content. Therefore, the material is particularly suited for parts requiring good corrosion resistance.

The intrinsic transient temperature difference between surface and inner volume during rapid cooling, together with asymmetric cooling condition at the top and bottom surfaces, yielded asymmetric thermal gradient within the slab. The asymmetric cooling condition inside the cooling pit has made the flat slab begin deflecting downward immediately after being plunged into the cooing pit. The asymmetric temperatures combined with an inelastic material behavior were determined to be responsible for the time-dependent deflection accompanying a reversal of the curvature for the slab. The shape of the slab may appear different depending on the staying time inside the cooling pit, and the observed instant for the slab. The low thermal conductivity or yield strength could display an increase for the final deflection. The results explained the physical cause of the deformation reasonably well.