ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Lattice diffusion of cobalt and nickel in Incoloy-800 has been studied in the temperature range 1070 to 1500K by serial sectioning and residual activity techniques using radioactive tracers60Co and63Ni. The lattice diffusion coefficient can be expressed by the relation: $$\begin{gathered} D_{Co/Incoloy - 800} = 2.54 x 10^{ - 5} exp \left( { - \frac{{249.5kJ mol^{ - 1} }}{{RT}}} \right)m^{^2 } sec^{ - 1} \hfill \\ D_{Ni/Incoloy - 800} = 8.62 x 10^{ - 5} exp \left( { - \frac{{255.9kJ mol^{ - 1} }}{{RT}}} \right)m^2 sec^{ - 1} \hfill \\ \end{gathered} $$ Segregation and mass transport studies of these tracers along the grain boundary in Incoloy-800 have also been carried out in the temperature range 750 to 1080 K. The grain boundary diffusion coefficients are evaluated by Whipple and Suzuoka methods and are found to be in good agreement. Grain boundary diffusivityD gb can be expressed by the equation $$\begin{gathered} D_{gb Co/Incoloy - 800} = 1.06 x 10^{ - 5} exp \left( { - \frac{{152.72kJ mol^{ - 1} }}{{RT}}} \right)m^2 sec^{ - 1} \hfill \\ D_{gb Ni/Incoloy - 800} = 3.82 x 10^{ - 5} exp \left( { - \frac{{156.40kJ mol^{ - 1} }}{{RT}}} \right)m^2 sec^{ - 1} \hfill \\ \end{gathered} $$ Segregation of these tracers along the grain boundary in Incoloy-800 has been studied by autoradiographic technique. The results have been discussed and presented in this paper.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01045364
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