Effect of strength on environment-assisted cracking of Ti–8V–6Cr–4Mo–4Zr–3Al in aqueous NaCl: Part II: Crack tip strain rate

摘要: Abstract The objective of this study is to critically examine the intrinsic environment-assisted cracking (EAC) resistances three microstructures Ti–8V–6Cr–4Mo–4Zr–3Al (Beta-C) in aqueous NaCl through variation crack tip strain rate. single-phase β microstructure Beta-C cold worked high strength, as well a β/α structure from short-term aging at 500°C, are immune EAC for range rates that should allow varying levels atomic hydrogen production and accumulation. Intergranular occurs underaged Beta-C, but only if driven by rate rapid loading or stable growth. Increased process-zone increased promotes embrittlement. severity ST/A increases with time constant These results strengthen Part I finding strength does not uniquely promote intergranular EAC; rather, grain boundary characteristics change during α-precipitation hardening govern β-Ti alloys.