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Reports results from studies conducted on a polyfunctional amine adduct epoxy curing agent (EPI‐CURE DPC‐3293) as a means to design low temperature cure coatings. Through the judicious choice of epoxide resins and amine‐functional curing agents, relatively fast reaction rates and resistance to moisture and humidity are maintained under low‐temperature cure conditions, and that is evidenced by a good balance of performance properties of coating films. We have used differential scanning calorimetry (DSC) to study the extent of reaction as well as the glass transition temperatures (T_g). Electrochemical impedance spectroscopy (EIS) has been used to predict the barrier properties of coating films. These results are compared with epoxide resins cured with a phenalkamine curing agent to illustrate some of the unique advantages of using multifunctional amine adduct curing agents for the curing of epoxide resins under sub‐ambient cure conditions for a multitude of end‐use applications.

The aerospace industry relies heavily on protective treatments and processes to ensure that the structural integrity of an aircraft is not degraded in service as a result of operating under harsh corrosive conditions. Many of the chemicals and processes currently employed in metal finishing have been found to cause pollution and long‐term damage to the environment. Legislation and international agreements are now in place which ultimately will lead to a ban or major reduction in the use of many of these processes and coatings. The aircraft constructors and operators are seeking to adopt new protective schemes and treatments which will satisfy future environmental requirements.

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

This paper aims to explore how the emerging cold spray technology could be integrated within a framework that finally could lead to more efficient aerospace operations.

The paper builds research question and hypotheses and answers them using support from authorities, evidence or logic.

The emerging cold spray process should not be viewed in isolation, but viewed as a component of a broad framework that should include materials, technologies, market, infrastructure and strategies.

This paper highlights that, for more efficient cold spray aerospace applications, there is a need for an interdisciplinary approach that crosses traditional disciplines, schools of thought and professions.

As technology becomes more complex, the need for coatings for specialised functions continues to increase. The electronics industry, for example, makes demands on the coating industry for both conductive and insulative coatings. Highly temperature‐resistant coatings played a key role in the aerospace industry. Fire retardant coatings contribute to consumer safety, and coatings for plastics serve a number of protective and decorative functions. The list could be extended appreciably. Some of its newer components will be described here.

The demand for titanium alloys has received massive attention in the aerospace and automotive industry owing to their magnificent electrochemically compatibility and corrosion resistance, high strength at elevated temperatures and high strength-to-weight ratio. Although titanium alloy has impressive mechanical properties, they are challenging to machine or metal form due to its poor heat conductivity, high chemical reactivity, low modulus of elasticity, high friction coefficient and difficult lubricant that limits its application field and increases wear. However, surface treatment coating with the strong metallurgical bond between the titanium alloy matrixes is novel technique to resolve these challenges. This research will illustrate the influence of laser scanning power on the microstructure and tribological behavior of Nickel (NI)-composite claddings fabricated on TC4 titanium alloy to realize the strong metallurgical bond between the titanium alloy and NI-composite coating.

In this research, TiC/TC4 alloy nanocomposites were fabricated based on different laser power and temperatures. TC4 has been selected as a base material instead of TiC for the strong metallurgical bond between the titanium alloy matrixes. Then Ni-composite coating was used as the surface treatment coating on TC4 by laser cladding (LC) technique. The Ni-based alloy coating material powder is good self-fluxing, has high-temperature resistance and is analytically pure with 200 mesh, which can easily overcome the various challenges of titanium alloy. The chemical properties of Ni composite coating include 31.2% Chromium, 8%Titenium and 3.6% Carbon. The prepared surface treatment coating characterization and microstructure behavior are analyzed using optical micrograph, X-ray diffraction, scanning electron microscopes, energy dispersive spectroscopy and electron probe micro analyzer methods.

It is evident that at the beginning of the experiment, if the laser power increased, the quality of the coating increased. An optimal quality of the coating is found when the laser scanning power about 12.55 kJ/cm². Further increased laser power diminished the quality of the coating because the material plasticity had deteriorated. The TiC ceramic particle reinforced phase is dispersed into a two-phase solid solution of β-Ti and γ-Ni. The micro-hardness of the used coating is greater than the base alloy.

This research has practical value in the modern aerospace and automobile industry to increase the application of titanium alloy.

Ion Deposition Ltd is a new company established in Corby, Northamptonshire, as part of the SATRA Group of companies which specialises in international operations in the metals business. IDL has been set up as a specialist coating facility — with the support of the Department of Trade and Industry — initially offering ion vapour deposition of aluminium to, in particular, the Aerospace Industry. Significant investment has been made in equipment and facilities, including the latest state‐of‐art ivadizer from McDonnell Douglas. The vacuum chamber is capable of accepting a component 5ft by 10ft, yet has a barrel coating insert for the processing of large volumes of small parts like rivets and fasteners. The coater is also fitted with the capability of the first cryogenic pumping system, which achieves lower vacuums quickly and efficiently. The IDL plant has been in full operation for seven months, and has already established a firm Aerospace orientated customer base both in the U.K. and mainland Europe. Future plans include the expansion of the Corby facility to include other highly specialised coating services to meet the needs of ‘high tech’ industries in the 1990s'.