Polymers possess several properties that make them useful as aircraft materials, including low density (1.2–1.4 g cm−3), moderate cost, excellent corrosion resistance, and high ductility (except thermosets). Figure 7.1. Nano-materials, such as nano-crsytalline tungsten-titanium diboride-copper composite, are potential candidates for enhancing these ignitors’ life and performance characteristics. The after-flame time and afterglow time are recorded for each specimen; the burn-through evaluation is performed by visual observation for each specimen during the flame application. The NSF workshop report on magnesium alloys  includes a quote “Al alloys of incredible strength were developed by Edisonian trial and error, over the course of 80 years. 1 shows the possibility of reducing the weight of aircraft components using composite materials reinforced with carbon-nano-tubes (CNT). For example, Fig. Table 16.9. The fracture mechanisms of other materials such as polymers and ceramics are briefly mentioned, but are not considered in detail because they are not used in large quantities in aircraft structures. Moreover, welding plays an important role not only in the assembly and manufacture of such components but also in the repair of small defects or damage that occurs during the fabrication process or actual use3). In order to suppress pore formation and achieve further grain refinement in the welded zone, friction stir welding (FSW), which is a method of solid-state welding, was employed for joining the plates. 19.1 Introduction. Change ), You are commenting using your Twitter account. Al alloys for primary structures and landing gear. The microstructure and mechanical properties of Ti-531C subjected to FSW, including the fatigue properties, were investigated in the present study. Related terms: Graphene; Aircraft; Polymer Composite; Material Selection; Alloy; Aluminum Alloys; Fatigue of Materials Damage tolerance and fracture resistance became key considerations in the selection of aircraft materials following the de Havilland Comet jet airliner accidents in the early 1950s. These aspects range from materials, manufacturing and processing techniques, to structures, design principles and structural performance, including aspects like durability and safety. In spacecrafts, elevated-temperature strength of the material, is crucial for components such as rocket engines, thrusters, and vectoring nozzles. Bronzes tend to be copper–tin alloys, although they may include the likes of aluminium, manganese or silicon. The flame is applied for 30 seconds, and then the burner moved at least 3 in. The most common metals in this group are molybdenum, niobium, tantalum and tungsten. This procedure is also based on a small-size specimen, placed at a 45-degree angle. Typical applications are for components for aircraft, material-handling equipment and portable power tools. The performance criteria are based on the average burned length (maximum 17 in.) For example, gold has good corrosion resistance and ductility and is used for electrical contacts and terminals. The typical seat cushion includes a central cushioning foam or foam assembly, a fire blocker to prevent the flame from penetrating the foam elements, and an upholstery textile. The fatigue strength increases with a reduction in the grain size of the material. Typical applications are again as electrical contacts, spark-plug electrodes and as catalysts in exhaust systems. Again, they tend to have good strength (higher than brasses) and corrosion resistance. In the previous study, the microstructure and mechanical properties of laser-welded Ti-531C plates were investigated. Part 3: Aerospace Structures. Stress corrosion cracking (SCC) in aerospace vehicles, , actual service cases of SCC in aerospace vehicles appear to be confined to, Krishnan K. Sankaran, Rajiv S. Mishra, in, Metallurgy and Design of Alloys with Hierarchical Microstructures, Flammability Testing of Materials Used in Construction, Transport and Mining, The fatigue performance of composites can be improved in various ways. Therefore, the improvement of welding techniques and the mechanical properties of the welded components are much sought after in the aerospace field. In this chapter, the inferior properties as compared to aluminum and titanium alloys are treated as real. Combine this with our unrivalled technical knowledge and logistical capabilities and you can rest assured that you are … This originated from the fact that conventional fire fighting methods are not effective against magnesium fire. Listed below are several specialist properties which may be considered in materials selection: Electrical conductivity is an important property for materials used in the outer skin of aircraft. Flammability properties such as ignition temperature, flame spread rate and smoke may need to be considered. voids, corrosion damage) are present in many aircraft components. This chapter examines the types of fracture processes that occur in metals and fibre–polymer composites used in aerospace structures.