Few More Effect of Nb on High Temp. Alloys. (1) Other than carbide former with enhanced creep strength Nb also acts as a Solid Solution Strengthener. (2) It has to be judiciously added and if added beyond it has detrimental effect on the High Temp. Oxidation resistance of the material. (3) One of the important aspect of refractory element Nb is that they capture and freeze strongly the high temperature Yield and Tensile Strength without reducing Ductility factors rather improving the Ductility even after Stress Relaxation Solution Annealing. with regards DM

We regularly produce Tube Support castings in this grade at our Foundry. We had also faced the problem of low elongation in the past but we could overcome the same by adopting better melting procedure, in particular the deoxidation procedure. The improvement in elongation was almost unbelievable. In my opinion, the problem is related to the cleanliness of the melt and not anything else. Regards, Kochappan.