| The tensile properties and corrosion resistance of martensitic 12Cr-1Mo steel containing 3 and 4 weight percent (wt%) Silicon (Si) have been evaluated in this investigation. The tensile data indicate that limited plasticity in terms of failure strain (ef) was observed at room temperature irrespective of the Si content. A significant drop in ef was observed with the steel containing 3 wt% Si at 400°C. For both alloys, there was a gradual drop in tensile strength with increasing temperature. The steel containing 3 wt% Si exhibited the maximum cracking susceptibility in the 90°C acidic solution, when tested by the slow-strain-rate technique. This alloy also showed enhanced cracking tendency in the same environment under controlled cathodic potential (Econt). However, the steel containing 4 wt% Si did not exhibit any effect of temperature and Econt on its cracking tendency. The magnitude of corrosion potential became more active (negative) with increasing temperature. The final stress intensity factor was significantly reduced at higher applied loads imparted by wedges in 100°C acidic solution. In general, the tested specimens exhibited brittle failures, as characterized by scanning electron microscopy. |
