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The effect of heat treatments on wire and arc additively manufactured Inconel 625 parts was investigated using in situ synchrotron X-ray diffraction and hardness testing. As-built samples revealed the presence of a γ -matrix with precipitation of γ , γ and MC carbides. When heat treated at 750°C for 4 h, γ phase precipitated increasing the hardness by 5%. In situ X-ray observations revealed that heat treating at 870°C for 1 h resulted in δ-phase precipitation. Two different second-stage temperatures were tested (1050°C and 1150°C), which dissolved the δ-phase while MC carbides formed upon cooling. The second stage at 1150°C had a higher deleterious effect than the one performed at 1050°C due to extensive grain growth.

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Ceramic pyrochlores, the basis of Bi2O3-ZnO-Nb2O5 (BZN), have dielectric properties of great interest, such a high dielectric constant (ε), a low dielectric loss tangent (tan δ) and a low coefficient of capacitance with temperature (TCC). The system has two main phases, Bi1,5ZnNb1,5O7 (α) and Bi2Zn0,67Nb1,33O7 (β) with cubic and orthorhombic crystal structures, and very different dielectric properties. The purpose of this article was to synthesize chemically homogeneous ceramic pyrochlores BZN-α and BZN-β, using the ceramic method in obtaining nanopowders and their characterizations by scanning electron microscopy (SEM), X-Ray Diffraction (XRD), and the Rietveld refinement method of the structures. The powders were weighed in stoichiometric proportions and calcined at 700 °C/2h, they were sintered at 900, 950 and 1000 °C/2h. A pure BZN-α phase was obtained, while the BZN-β has remained in phases as Bi5Nb3O15 and BiNbO4.