Effect of S on Solidification Behavior of Cast Superalloy K417G
The effects of 0.000 1％,0.001 8％and 0.003 7％S content on the solidification characteristics of K417G al-loy were studied by isothermal solidification experiment in the temperature range of 1 340-1 230 ℃.The results show that S can reduce the solidus temperature of the alloy and enlarge the solid-liquid two phase region.When the S content in-creases from 0.000 1％to 0.003 7％,the solidus temperature of the alloy decreases from 1 255 ℃ to 1 245 ℃.During the solidification process,the S element segregates in the liquid phase and precipitates out as the Y phase in the final solidifi-cation zone.And S promotes the enrichment of Al and Cr elements at the solid-liquid interface.At the same isothermal temperature,the increase of S content promotes the increase of the volume fraction of MC carbide,γ+γ'eutectic and Y phase,and has little effect on the morphology and precipitation temperature of MC carbide and γ+γ'eutectic,but the pre-cipitation temperature of the Y phase is increased from 1 230 ℃ to 1 240 ℃.
万方数据
维普
