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The effects of a number of metals and alloys on the thermal stability of Avtur 50 have been evaluated from ASTM‐CRC and high temperature coker tests. The materials tested are used in current aircraft fuel systems or are possible alternatives for fuel systems of supersonic aircraft where they will be in contact with hot fuel. The alloys currently used in aircraft fuel systems have been classified and their probable effects on the stability of hot fuel listed. A number of the materials affected stability adversely, particularly alloys containing significant amounts of copper, and the use of these should be avoided. The pick‐up of copper by Avtur 50 at ambient temperature from alloys such as brass and gun‐metal has also been investigated. The results indicated that sufficient copper to affect thermal stability adversely is readily picked up from these alloys.

THIS paper shows briefly the origins and development of a comparatively new and certainly important branch of engineering science. For many years the alloys of the light metals, particularly of aluminium and magnesium, have been developed, until the term “light alloys” has come to be generally accepted as indicating the alloys of the light metals or any metallic alloy having a density of less than about 3·8. Towards the other end of the density scale are now being developed alloys of the heavy metals, mainly tungsten and tantalum. The techniques of production and manufacture of these two groups are very different: whereas the light alloys are produced and manipulated mainly by melting, casting, annealing, and forging, the heavy alloys are produced by various processes of powder metallurgy, resulting in substances with densities of 15 or more.

Geigy Co. Ltd. Stand 75. Diversified application of benzotriazole as a corrosion inhibitor specifically for copper and its alloys is the main theme of Geigy's stand.

IN recent years several interesting and excellent papers have been read before various Societies, dealing with magnesium and its alloys.

THE use of metals at temperatures in excess of 1,200 deg. F. and up to temperatures in the vicinity of their melting points is a challenging and fascinating portion of the fight to pass the heat barrier in the design and performance of aircraft and their power plants. The materials available for service in this temperature range are restricted. The considerations of designing structural components involve many more problems than the old criteria of strength to weight ratio and fabrication costs. Such properties as thermal expansion, heat conductivity, surface emissivity and scaling resistance are as important in determining which metal should be used for a given application as are the various measurements of strength heretofore the primary considerations in material selection.

It is perhaps not unfitting that I should begin my lecture by asking a rhetorical question:

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

This paper aims to propose a method that can directly print low-melting-point alloy In61Bi26Sn9Ga4 into a variety of macroscopic 3D structures at room temperature via adhesion mechanism.

In the first section, the principle of the direct printing system is described. As process parameters and material properties have both geometric and physical significance to printing, the approach the authors take is to study the relationships between key parameters and ultimate printed dimension. The surface tension of the fusible alloy is measured under different temperature ranges.

The interaction between the initial standoff distance and the geometry of the first layer is critically important for the adhesion of the liquid metal to the substrate and metal deposition. The characterization of the layer stacking in the direct printing process, stability ranges of the layer thickness and printing speed are also demonstrated. The direct printing system is suitable for making 3D structures with low-melting-point alloy under the summarized range of printing conditions.

This study may arouse big public attention among society.

This study shows possibilities of manufacturing macroscopic 3D metal objects by continuously depositing molten alloy with low viscosity and high surface tension around room temperature. This study provides a supplement to realize compound printing with metal and nonmetal materials together for building terminal functional devices in a low cost and efficient way.

THROUGHOUT the history of the advance of aviation the development of light alloys occurs and recurs as a silver thread, lightening the pattern. From the very first the possibility of aviation has been bound up with the design of the prime mover, and the remarkable strides made during the past two decades in the production of power from a minimum of weight are largely due to the alloys of aluminium, their strength and rigidity for a given weight, their thermal properties, and their capacity for prolonged, reliable service.

THROUGHOUT recorded history metals have played an important role in the development of civilised life. In fact they have been used as markers for stages in that development — hence the terms bronze age and iron age. We would appear to be still living in what could be called the late steel age. In spite of changes in patterns of metal use we shall stay in this age at least well into the 21st century.