GH4199合金渗铝工艺研究

Study on GH4199 alloy aluminizing process

主要针对渗铝工艺中不同渗铝温度、保温时间对GH4199合金组织、性能影响进行试验,试验结果表明渗层组织由表及里分别为:表层主要为富铝的NiAl相,向内的过渡层和扩散层为富Cr相、碳化物、NiAl相和Ni3 Al相等。渗层厚度的变化主要与温度和时间有关,同一渗铝温度下,随着渗铝时间的增加渗铝层深度增加;同一渗铝时间,随着渗铝温度的提高渗铝层深度增加。经渗铝处理后,室温拉伸强度提高,拉伸塑性降低。900℃拉伸强度降低,拉伸塑性提高;持久寿命稍降低,塑性提高。

This paper mainly discusses the effects of different temperatures and holding times on the struc- ture and properties of GH4199 alloy. Results show that from the outside to the inside the aluminizing layers are respectively rich aluminum NiA1 phase, mainly in the surface layer, and rich Cr phase, carbide, NiAl phase and Ni3Al phase in the transition layer and diffusing layer. The thickness of aluminizing layers is mainly related to temperature and time. At the same temperature, the thickness of aluminizing layers increases with increasing aluminizing time; at the same time, the thickness of aluminizing layers increases with increasing aluminizing temperature. At room temperature the tensile strength of GH4199 alloy increases and the tensile ductility decreases. At 900℃ the tensile strength decreases, the tensile ductility increases, the creep rupture life reduces slightly and the ductility increases.