Understanding Interfacial Reactions in Ti-Ni Diffusion Couple.

The diffusion phenomenon in the Ti-Ni binary system was investigated at a temperature of 1173 K. Microstructure and texture analysis revealed the formation of three stable intermetallic compounds, namely Ti2Ni, TiNi, and TiNi3, as well as two metastable intermetallic compounds, including Ti3Ni4 and Ti2Ni3, at the interfacial diffusion zone. The nucleation surface energy increase was analytically estimated, and marker experiments were conducted using thoria particles, both of which showed that Ti2Ni was the first compound to form at the Ti-Ni diffusion interface. At a temperature of 1173 K, using the Wagner method, the integrated diffusion coefficients for the Ti2Ni, TiNi, and TiNi3 phases were calculated to be 3.53 × 10-12, 18.1 × 10-15, and 6.2 × 10-15 m2/s, for, respectively.

Li-Doped Bioactive Ceramics: Promising Biomaterials for Tissue Engineering and Regenerative Medicine.

Lithium (Li) is a metal with critical therapeutic properties ranging from the treatment of bipolar depression to antibacterial, anticancer, antiviral and pro-regenerative effects. This element can be incorporated into the structure of various biomaterials through the inclusion of Li chloride/carbonate into polymeric matrices or being doped in bioceramics. The biocompatibility and multifunctionality of Li-doped bioceramics present many opportunities for biomedical researchers and clinicians. Li-doped bioceramics (capable of immunomodulation) have been used extensively for bone and tooth regeneration, and they have great potential for cartilage/nerve regeneration, osteochondral repair, and wound healing. The synergistic effect of Li in combination with other anticancer drugs as well as the anticancer properties of Li underline the rationale that bioceramics doped with Li may be impactful in cancer treatments. The role of Li in autophagy may explain its impact in regenerative, antiviral, and anticancer research. The combination of Li-doped bioceramics with polymers can provide new biomaterials with suitable flexibility, especially as bio-ink used in 3D printing for clinical applications of tissue engineering. Such Li-doped biomaterials have significant clinical potential in the foreseeable future.

Microstructural evolution and resulting properties of differently sintered and heat-treated binder-jet 3D-printed Stellite 6.

Stellite 6 components are manufactured from gas-atomized powder using binder-jet 3D-printing (BJ3DP) followed by curing and sintering steps for densification. Green parts are sintered at temperatures ranging from 1260 °C to 1310 °C for 1 h. Microstructural evolution and phase formation during sintering and aging are studied by optical and scanning electron microscopy, elemental analysis and X-ray diffraction. It was found that solid-state sintering was present at temperatures below 1280 °C with Cr-rich carbides present within grains; while supersolidus liquid phase sintering was the dominant sintering mechanism during sintering at 1290 °C and higher in which the Co-rich solid solution regions are surrounded by eutectic carbides. Sintering at 1300 °C resulted in the maximum density of ~99.8%, mean grain size of ~98 ±â€¯6 µm with an average hardness of 307 ±â€¯15 HV0.1 and 484 ±â€¯30 HV0.1 within grain and at the boundaries, respectively. Aging was performed at 900 °C for 10 h leading to the martensitic transformation (fcc → hcp) as well as an increase in eutectic carbides at boundaries and nano-sized carbides within grains where the average hardness within grains and boundaries was enhanced to 322 ±â€¯29 HV0.1 and 491 ±â€¯58 HV0.1, respectively. Fibroblasts seeded on top of 3D-printed Stellite 6 discs displayed a cell viability of 98.8% ±â€¯0.2% after 48 h, which confirmed that these materials are non-cytotoxic. Presented results demonstrate that binder jetting can produce mechanically sound complex-shaped structures as shown here on a denture metal framework and small-scale knee model.

Data on the densification during sintering of binder jet printed samples made from water- and gas-atomized alloy 625 powders.

Binder jet printing (BJP) is a metal additive manufacturing method that manufactures parts with complex geometry by depositing powder layer-by-layer, selectively joining particles in each layer with a polymeric binder and finally curing the binder. After the printing process, the parts still in the powder bed must be sintered to achieve full densification (A. Mostafaei, Y. Behnamian, Y.L. Krimer, E.L. Stevens, J.L. Luo, M. Chmielus, 2016; A. Mostafaei, E. Stevens, E. Hughes, S. Biery, C. Hilla, M. Chmielus, 2016; A. Mostafaei, Y. Behnamian, Y.L. Krimer, E.L. Stevens, J.L. Luo, M. Chmielus, 2016) [1-3]. The collected data presents the characterization of the as-received gas- and water-atomized alloy 625 powders, BJP processing parameters and density of the sintered samples. The effect of sintering temperatures on the microstructure and the relative density of binder jet printed parts made from differently atomized nickel-based superalloy 625 powders are briefly compared in this paper. Detailed data can be found in the original published papers by authors in (A. Mostafaei, J. Toman, E.L. Stevens, E.T. Hughes, Y.L. Krimer, M. Chmielus, 2017) [4].

Brief data overview of differently heat treated binder jet printed samples made from argon atomized alloy 625 powder.

Powder bed binder jet printing (BJP) is an additive manufacturing method in which powder is deposited layer-by-layer and selectively joined in each layer with binder. The data presented here relates to the characterization of the as-received feedstock powder, BJP processing parameters, sample preparation and sintering profile ("Effect of solutionizing and aging on the microstructure and mechanical properties of powder bed binder jet printed nickel-based superalloy 625" (A. Mostafaei, Y. Behnamian, Y.L. Krimer, E.L. Stevens, J.L. Luo, M. Chmielus, 2016) [1], "Powder bed binder jet printed alloy 625: densification, microstructure and mechanical properties" (A. Mostafaei, E. Stevens, E. Hughes, S. Biery, C. Hilla, M. Chmielus, 2016) [2]). The data presented here relates to the characterization of the as-received feedstock powder, BJP processing parameters, sample preparation and sintering profile. Effect of post heat treatments including solutionizing and aging on the microstructure and mechanical properties of powder bed binder jet printed nickel-based superalloy 625 were compared to that of sintered samples.