Producing single crystal superalloy using seed technique was preferred compared to spiral grain selector because of better mechanical properties. However, process control in the seeding method is more sensitive. In this investigation, single crystal super alloy PWA1483 using initial seed was manufacturied. For this purpose, initial seeds were produced using spiral grain selector. Evaluation of the effect of various process parameters on production of single crystal was performed and the influence of withdrawal rate and mold geometry on the orientation of single crystal was studied. Process simulation using ProCast ® software was also conducted. Simulation result was validated using both experimental and mathematical calculations. Results show that with increasing the withdrawal rate up to 9 mm/min, orientation of the single crystal declines in the mold of 40 mm starter block. However, misorientation of the single crystal increases after withdrawal rates of 9 mm/min. also, it was determined that, withdrawal rate, starter block size, and thermal gradient we interdependent variables such that, obtaining lowest single crystal deviation needs optimum mode of these parameters. Experimental studies show that the effect of starter block size is more important than withdrawal rate. Finally, an optimum withdrawal rate with a suitable starter block size is proposed. Then, the effect of process variables and seed characteristics on the produced single crystal were studied. It was found out that misorientation of seed is higher than the final single crystal. Also, it was found out that withdrawal rate history and the dendrite arm spacing does not affect final dendrite structure.
