There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Additive manufacturing of metallic components – Process, structure and properties

Freedom of design, mass customisation, waste minimisation and the ability to manufacture complex structures, as well as fast prototyping, are the main benefits of additive manufacturing (AM) or 3D printing. A comprehensive review of the main 3D printing methods, materials and their development in trending applications was carried out. In particular, the revolutionary applications of AM in biomedical, aerospace, buildings and protective structures were discussed. The current state of materials development, including metal alloys, polymer composites, ceramics and concrete, was presented. In addition, this paper discussed the main processing challenges with void formation, anisotropic behaviour, the limitation of computer design and layer-by-layer appearance. Overall, this paper gives an overview of 3D printing, including a survey on its benefits and drawbacks as a benchmark for future research and development.

Additive manufacturing (3D printing): A review of materials, methods, applications and challenges

Additive manufacturing of metals

Tailoring the partitioning behavior of solid solution strengtheners is a crucial design strategy for advanced Ni-based superalloys. The goal of this study was to maximize the enrichment of Mo, Re, Ru and W in the γ-matrix phase. To determine the composition dependency of the partitioning behavior, a set of polycrystalline superalloys with varying contents of these solid solution-strengthening elements and a W-containing single-crystalline alloy series with varying concentrations of the γ′-forming elements Ta and Ti was produced. Assessed properties include phase compositions by electron-probe micro-analysis, phase transformation temperatures by differential scanning calorimetry and creep behavior. Re exhibits the most pronounced enrichment in the γ-matrix, followed by Mo, Ru and W. Due to the preference of the Al-sites in the γ′-phase in the order Ta > Ti > W > Mo > Re, the solid solution strengthening elements Mo, Re and W are displaced from the γ′-phase by increasing Ti and Ta contents. The investigated solutes do not directly influence the partitioning behavior of Ru as it prefers Ni-sites in the γ′-phase. Compressive creep experiments reveal a correlation between the content of solid solution strengtheners in the γ-phase and creep performance.

Improving the Effectiveness of the Solid-Solution-Strengthening Elements Mo, Re, Ru and W in Single-Crystalline Nickel-Based Superalloys

In-situ AlTi particle reinforcement for stiff aluminum die castings

Titanium aluminides are highly attractive for high temperature applications involving dynamic components, e.g. turbine blades or turbocharger wheels, due to their high strength-to-weight ratio. The drawback is the difficult manufacturing of this material class due to the low toughness and high sensitivity to oxygen. Selective electron beam melting SEBM shows a new approach of producing complex titanium aluminide parts without a major oxygen pick up and avoiding problems with brittleness. The high cooling rates of this process lead to a very fine microstructure, which is not fully understood up to now. The microstructure determines the creep properties and therefore defines the performance of this material in high temperature applications. In this contribution, the creep properties of Ti-48Al-2Cr-2Nb fabricated by SEBM are investigated. The influence of the processing parameters and the building direction on the microstructure and the creep properties are discussed and compared to cast material.

Creep Properties of Ti-48Al-2Cr-2Nb Produced by Selective Electron Beam Melting

Influence of the microstructural homogeneity on the high-temperature oxidation behavior of a single crystalline Ni-base superalloy

https://onlinelibrary.wiley.com/doi/epdf/10.1002/adem.201901270

Carolin Körner

Papers

Improving the Effectiveness of the Solid-Solution-Strengthening Elements Mo, Re, Ru and W in Single-Crystalline Nickel-Based Superalloys

In-situ AlTi particle reinforcement for stiff aluminum die castings

Creep Properties of Ti-48Al-2Cr-2Nb Produced by Selective Electron Beam Melting

Influence of the microstructural homogeneity on the high-temperature oxidation behavior of a single crystalline Ni-base superalloy

S𝔸𝕄PLE: A Software Suite to Predict Consolidation and Microstructure for Powder Bed Fusion Additive Manufacturing

Carolin Körner

Papers

Improving the Effectiveness of the Solid-Solution-Strengthening Elements Mo, Re, Ru and W in Single-Crystalline Nickel-Based Superalloys

In-situ AlTi particle reinforcement for stiff aluminum die castings

Creep Properties of Ti-48Al-2Cr-2Nb Produced by Selective Electron Beam Melting

Influence of the microstructural homogeneity on the high-temperature oxidation behavior of a single crystalline Ni-base superalloy

S&#x1d538;&#x1d544;PLE: A Software Suite to Predict Consolidation and Microstructure for Powder Bed Fusion Additive Manufacturing

S𝔸𝕄PLE: A Software Suite to Predict Consolidation and Microstructure for Powder Bed Fusion Additive Manufacturing