Functionally Graded 3D-Printed Scaffolds through Direct Ink Writing: Bridging Ceramics and Metals for Enhanced Multifunctionality

Over two million bone grafts are performed worldwide, each year. The preferred method is using autografts, but there are two important downsides. There is often insufficient tissue to harvest and the scar at the harvesting side is painfull for the patient. Therefore there exists a great need to improve synthetic grafts.<br/><br/>Traditionally,...

A review on mechanical alloying and spark plasma sintering of refractory high-entropy alloys: Challenges, microstructures, and mechanical behavior

Refractory high-entropy alloys (RHEAs) are promising candidates for those applications requiring of strong materials at high temperatures with elevated thermal stability and excellent oxidation, irradiation, and corrosion resistance. Particularly, RHEAs synthesized using mechanical alloying (MA) followed by spark plasma sintering (SPS) has...

Design of In Situ Metal Matrix Composites Produced by Powder Metallurgy: A Critical Review

In situ composite manufacture is an approach to improve interfacial adhesion between matrix and reinforcements, in which reinforcements are synthesized along composite processing itself. In situ powder metallurgy route, in particular, offers alternatives to some shortcomings found in other techniques. This work aims not only to review the state...

Effect of Hot Isostatic Pressing on the Microstructure of Directionally Solidified Nickel Alloy After SLM

The paper investigates the effect of hot isostatic pressing of single-crystal nickel-based alloy manufactured by selective laser melting (SLM) with a high-temperature substrate preheating. A study of the structure and phase composition of the material before and after treatment has been carried out. It was found that as a result of such...

On the powder metallurgy, additive manufacturing and welding of oxide dispersion strengthened Eurofer steel

Oxide dispersion strengthened (ODS) steels are promising candidates for use as structural materials in the next generation fission and fusion reactors. Compared to conventional ferritic or martensitic steels, ODS steels exhibit improved high-temperature creep properties and irradiation resistance. Favourable properties are mainly attributed to...

Heat treatment effect on the structure formation of directionally solidified nickel alloy after SLM

The aim of this study was to determine the influence of heat treatment on the microstructure of single-crystal nickel-based alloy manufactured by selective laser melting with a high-temperature substrate preheating. The change of gamma/gamma prime -phases ratio was established as a result of various heat treatment modes.

Microstructure characterisation and mechanical properties of ODS Eurofer steel subject to designed heat treatments

The present work deals with oxide dispersion strengthened (ODS) Eurofer steel fabricated by powder metallurgy involving mechanical alloying and spark plasma sintering. A heat treatment route including normalising and tempering was applied to the as-produced steel, based on differential scanning calorimetry (DSC) measurement. The...

Effect of mechanical alloying and spark plasma sintering on the microstructure and mechanical properties of ODS Eurofer

Oxide dispersion strengthened (ODS)Eurofer steel was prepared via mechanical alloying (MA)and spark plasma sintering (SPS). Different combinations of MA and SPS parameters were adopted in order to optimise the fabrication process. The experimental results show that the sample milled for 30 h, sintered at 1373 K at a pressure of 60 MPa has...

Fabrication of metallic biomedical scaffolds with the space holder method: A review

Bone tissue engineering has been increasingly studied as an alternative approach to bone defect reconstruction. In this approach, new bone cells are stimulated to grow and heal the defect with the aid of a scaffold that serves as a medium for bone cell formation and growth. Scaffolds made of metallic materials have preferably been chosen for...

Engineering property comparisons of PM alloy X7091-T7E69 and IM alloy forgings

The engineering properties of PM alloy X7091-T7E69 forgings were compared with those of forgings of the IM alloys 7075-T73, 7175-T736, 7050-T736 and 7010-T736. The properties considered were: strength, fracture toughness, fatigue crack propagation under constant amplitude and flight simulation loading, stress corrosion crack initiation and...

Operating conditions and materials selection and development in gas turbines

This paper consists of two parts. In the first part, concerning operational conditions in gas turbines, the following topics are covered: - the magnitude of temperatures, temperature profiles, and stresses in various components - transient temperature conditions, occuring as a result of e.g. throttle setting changes and affecting thermal fatigue...

Aluminium alloys for advanced structural applications in transport aircraft

This paper concisely reviews and discusses (1) metallurgically cleaner alloys like -2124, 2048 and 7475, (2) potential application of 7000 series alloys in tension panels, (3) development of high strength stress corrosion resistant thick section materials like 7010, 7049 and 705O, (4) powder metallurgy 7000 series alloys with high strength and...