The production of Fe-based intermetallics by microwave sintering and their diffusion bonding

Industrial parts manufactured by powder metallurgy method has an advantage of low-cost, low-density and can also be easily manufactured. In addition, they show high oxidation resistance at high temperatures. Potential applications as structural materials for FeAl and Fe3Al intermetallic compounds, the studies focus on the minimization of difficulties experienced in the manufacturing process. In order to optimize the manufacture by powder metallurgy method, Fe-Al and Fe-Al-Ti powder mixtures were produced by both conventional and microwave sintering methods and diffusion bonding was employed to join the microwave sintered powder mixtures. The microwave sintering of Fe-Al and Fe-Al-Ti mixtures could not be seen in the literature and this contributes to the authenticity of this study.In this study, Al of 75?m, Ti and Fe of 45?m and high purity powders better than > 99% are used. The powder in different ratios of Fe-26Al, Fe-30Al, Fe-33Al and Fe-26Al-14Ti/16/20, Fe-30Al-14Ti/16/20, Fe-33Al-14Ti/16/20 homogeneous mixture without providing a binding uniaxial compaction has been achieved by making the raw strength. Microwave and conventional furnace sintering of the samples in argon atmosphere, at temperatures of 450, 500 550, 600, 650, 700, 750, 800 0C, and also at the same temperatures in a vacuum in the silica tube silica was produced. Sintering durations of 0,5, 1 and 1,5 hours were selected. Temperatures at high and low ends of the scale were found to be unfeasible for the manufacturing of the specimens. Therefore, temperatures of 550C and 650C were selected for this study. Diffusion bonding at 600 0C and 3 MPa pressure for 60 minutes was performed in a vacuum. The shear strength of samples that are diffusion bonded using Cu interlayer was found close to the strength of the powder compacts.XRD and SEM analysis of sintered samples were evaluated. The shear strength and hardness were measured with respect to the sintering temperature. THe microstructural analysis and the shear strength of the specimens produced by diffusion bonding. Iosepescu method was used for determining the shear strength of the samples. The shear strength values as high as 70 MPa in sintered samples and shear strength values as high as MPa in diffusion bonded specimens were measured.Keywords: Diffusion Bonding, Intermetallics, Powder Metallurgy, Sintering