The effects of chemistry variations on hot cracking susceptibility of Haynes® 282® for aerospace applications

• Published in: Materials & design Vol. 228; p. 111853
• Main Authors: Singh, Sukhdeep, Kadoi, Kota, Ojo, Olanrewaju, Alexandrov, Boian, Andersson, Joel
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-04-2023; Elsevier
• Subjects: Boron segregation; Carbon segregation; Liquation cracking; NanoSIMS; Production Technology; Produktionsteknik; Solidification cracking; Superalloy; NanoSIMS; Superalloy; Liquation cracking; Carbon segregation; Solidification cracking; Boron segregation; Grain boundaries; Crack-healing; Superalloys; Heat-affected zones; Thermodynamics; Titanium alloys; Borides; Boron; Molybdenum compounds; Eutectics; Cracking susceptibility; Scanning electron microscopy; Silicides; Secondary ion mass spectrometry; Carbon; Solidification; Binary alloys; Solid solutions; Titanium compounds; Hot-cracking; Carbides; Cracking extents
• ISSN: 0264-1275; 1873-4197; 1873-4197
• DOI: 10.1016/j.matdes.2023.111853

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•Solidification and HAZ liquation cracking susceptibility is primarily correlated to the C and B content.•Lower C and B promotes solidification cracking. When increasing C and B, the solidification cracking is reduced by crack healing by eutectics.•The lower susceptibility towards liquation cracking susceptibility is attributable to the lower amount of Ti-Mo carbides and Mo borides.•High temperature homogenization heat treatment at 1190 °C excarbates the cracking by dissolving the borides and releasing B to the grain boundaries.
Hot cracking susceptibility of Haynes® 282® with varying amount of C (0.05–0.09 wt%), Mn (0.03–0.12 wt%), Si (0.03–0.16), B (0.005–0.006 wt%) and Zr (0–0.01) are investigated. Synergistic role of C and B is found on solidification and heat affected zone (HAZ) liquation cracking susceptibility. High amount of C and B promote formation of eutectic constituents during final stages of solidification and promote crack healing by backfilling effect. When C and B are added in low amount the crack healing does not occur due to the absence of eutectic consituents therefore cracking extent increases. Thermodynamics simulations indicate C and B tie up to MC carbides and M3B2 borides during solidification. Scanning Electron Microscopy and Nanoscale secondary ion mass spectrometry analysis reveal C and B to be present both in solid solution and in form of precipitates to Ti-Mo rich carbides and Mo rich borides, respectively. In HAZ, these phases promote liquation cracking where cracking extent correlates to the amount carbides and borides. Lower C and B is found to reduce the liquation cracking in the HAZ. Furthermore, a high temperature homogenization heat treatment at 1190 °C excarbates the cracking by dissolving the borides and releasing B to the grain boundaries.