Stress-Strain Curves and Crack Formation in an Ingot of Stainless Steel 21-4N Under High-Temperature Compression

High-Temperature Deformability of a Fe-Cr-Mn-Ni Austenite Stainless Steel with High Nitrogen and High Carbon Contents

“…The Cr2N phase was not easily observed in the groove-rolled high-nitrogen high-carbon Fe-Cr-Mn-Ni rod of the present study. In the as-cast ingot of high-carbon high-nitrogen Fe-Cr-Mn-Ni, extensive precipitation and growth of lamellar Cr2N was observed at the grain boundaries in the temperature range of 800-900 °C [14]. Erisir et al [7] also observed Cr2N at grain boundaries in the high nitrogen (0.8 wt.%) as-cast Fe-Cr-Mn-Mo-Ni steel ingot.…”

“…In Figure 9a, the reduction of area increased gradually up to 950 • C, and then more rapidly up to 1100 • C. It decreased slightly at 1200 • C, and then plummeted to merely 1-2% at 1250 • C. It should be noted that the loss of strength as well as that of ductility occurred at 1250 • C. The effective fracture elongation did not change much up to 900 °C , but it increased rapidly from 1000 °C and reached high values, above 45%, at 1100-1200 °C . The slight decrease of fracture elongation at 850 °C may be attributed to the Cr2N precipitation in the temperature range of 800-900 °C [7,14,21]. The high temperature deformability of Fe-Cr-Mn-Ni stainless steel can be predicted satisfactorily by the effective fracture elongation, calculated using Equations (1) and (2).…”

“…M 23 C 6 and Cr 2 N were found to be completely dissolved at 1170 • C and 1000 • C, respectively, for the Fe-21.7 Cr-9.7 Mn-3.4 Ni steel with 0.40 wt.% nitrogen and 0.51 wt.% carbon. As shown in Figure 3, Cr 2 N was less stable at high temperatures and its mass fraction was much smaller than that of M 23 C 6 ; it may have less influence on the hot deformability than M 23 C 6 [14]. The mass fraction of Cr 2 N at 800 • C (3%) in the high-nitrogen high-carbon stainless steel of the present study was smaller than that in carbon-free high nitrogen Fe-12.4 Mn-16.1 Cr-3.3 Mo steel (7.3%), as reported by Erisir et al [7].…”

Numerical Simulation on the Fluid Flow, Air Entrainment, Heat Transfer, and Solidification during Top Pouring and Cooling of a 303 Ton Heavy Ingot

“…The entrainment of the air and mold powders during the initial filling process is of significance to the cleanliness and the quality of the ingot product. [2,3] Investigations have been performed to improve and control the flow pattern during the ingot filling process, [4][5][6][7][8] and extensive studies have been done on the heat transfer, [9,10] shrinkage cavity, [11][12][13] crack, [14,15] stress-strain, [16][17][18] segregation, [19][20][21] and the generation and removal of inclusions [3,22] during the cooling and solidification process of the steel ingot. Zhang et al [23] studied the influence of argon hood protection devices on air absorption and reoxidation during filling.…”