The Isothermal Section Of The Phase Diagram Of The Dy-Mn-Ti Ternary System At 500℃

The phase relationship in the Dy-Mn-Ti ternary system at 500℃ has been studied mainly by means of X-ray powder diffraction with the aid of differential thermal analysis and optical microscope. There are 11 single-phase regions, 19 two-phase regions and 9 three-phase regions in this ternary system at 500℃. No ternary compounds were found.The 11 single-phase regions are: α(Dy), β(Ti), γ(Mn₁₅Ti₈₅), δ(αMnTi), ε(pMnTi), ζ(Mn₂Ti), η(Mn₅Ti), θ(Mn), ι(DyMn₁₂), κ(Dy₆Mn₂₃) and λ(DyMn₂).The 19 two-phase regions are: α+β, β+γ, γ+δ, δ+ε,ε+ζ, ζ+η, η+θ, θ+ι, ι+κ, κ+λ, λ+α, α+γ, α+δ, α+ε, α+ ζ, ζ+λ, ζ+κ,η+κ and θ+κ.The 9 three-phase regions are: α+β+γ, α+γ+δ, α+ε+ζ, α+ζ+λ, ζ+κ+λ, ζ+η+κ, η+θ+κ and θ+ι+κ.The maximum solid solubility of Ti in Mn, DyMn₁₂, Dy₆Mn₂₃, and DyMn₂ are about 8at. %, 3 at. %, 3.5 at. %, 3.5 at. % Ti respectively, determined by the varying of the lattice parameters along with the vanishment of phase. And the homogeneity range of Mn₂Ti extends from about 61at% to 69at% Mn.No ternary compounds were found in this ternary system.