GH36合金中M<sub>23</sub>C<sub>6</sub>、VC的界面結構

GH36合金中M₂₃C₆、VC的界面結構

摘要: 使用透射電鏡觀察了GH36合金中M₂₃C₆、VC碳化物和基體之間的界面結構,在M₂₃C₆/γ的半共格界面上分布有錯配位錯列,間距約10nm。根據\rm\vec g·\rm\vec b=0判據,可以確定該位錯的Burgers vector \rm\vec b=a/2(110)γ,VC/γ的相界面是具有很大點陳錯配度(δ=+0.155)的共格界面。最后,從M₂₃C₆、VC和基體之間的不同界面結構與性質討論了以碳化物沉淀為主要強化手段的Fe基GH36合金的強韌化本質以及如何識別波紋圖(Moire pattern)和界面位錯的問題。

Abstract: A TEM study on the interfacial structure of M₂₃C₆/γ and VC/γ precipitated in GH36 superalloys was conducted. The misfit dislocation distribution has been clearly observed at the semi-coherent interfaces of M₂₃C₆/γ, a single array along the broadfaces at both sides with Burgers Vector a/2 <110>γ and spaced about 10 nm apart. It has been shown circular strain field constrast around the very fine dispersive VC particles of 3 to 12nm or so in size. In addition, strengthening mechanism of M₂₃C₆ and VC precipitated in GH36 superalloy, and how to identify the moire pattern or interfacial dislocations by TEM, were also discussed.