Showing papers on "Aluminium alloy published in 1973"

Method of producing a dispersion-strengthened aluminum alloy article

Abstract: Aluminium alloy articles of high strength and high resistance to temperature softening are produced by spraying droplets of selected aluminium alloy entrained in a stream of gas onto a substrate under such conditions that the metal droplets strike the substrate in a highly undercooled (supercooled) condition. On striking the substrate the undercooled liquid droplets flatten and are very rapidly chilled so that the alloying constituent is either maintained in supersaturated solid solution or is precipitated as a very fine precipitate. The deposit is consolidated by warm working. The selected aluminium alloy contains up to 25 percent of alloying constituent, which is in excess of the equilibrium solid solubility and has a low diffusion rate in aluminium. The preferred alloying constituents are one or more of Ti, V, Cr, Mn, Fe, Co, Ni, Zr, Nb and Mo. Si may be added but is unsuitable by itself. Particularly satisfactory results are obtained with eutectic ternary alloys containing Ni or Si.

Study of the Injection Upsetting of Metals

Abstract: The punch pressure required to injection upset a cylindrical billet of an isotropic, non-work-hardening, rigid–plastic material is derived using an upper bound (velocity field) technique and by a ‘slab’ stress analysis. A method for applying the theory to the injection upsetting of work-hardening materials is evolved and the validity of this application is demonstrated by the results of experiments using pure aluminium, an aluminium alloy and copper.

The effect of elevated temperatures on the mechanical properties of B-Al composites.

Abstract: The mechanical properties of an aluminium alloy reinforced with 20 and 50 vol % boron fibres have been obtained from specimens in the “as-received” condition and after heating to 600° C for various periods of time. Heating the specimens caused a reduction in the load-bearing capacity of each specimen and the eventual growth of a reacted layer at the fibre-matrix interface. As-received specimens fractured in a sudden brittle manner; however, those specimens heated for 4 h at 600° C slowly pulled apart. The variation in the static strength of the as-received and the heated specimens is explained in terms of upper and lower bounds calculated from a knowledge of the statistical strength variation exhibited by individual fibres.

Fatigue crack growth in aluminium alloy shee material under flight-simulation loading: effects of design stress level and loading frequency

Abstract: Specimens of 2024-T3 and 7075-T6 were tested at 10, 1 and 0.1 cps. Values of mean stress in flight were 10.0, 8.5, 7.0, 5.5 and 4.0 kg/mm(2). The analysis of the results bears upon the frequency effect and its significance for inspection periods in service, the effect of stress level, a comparison between the two alloys, the prediction of crack rates in flight-simulation tests and the meaning of the stress intensity factor for the latter purpose.

The thickness effect in plane stress fracture toughness

Abstract: Residual strength tests were carried out on center cracked aluminium alloy panels of various thicknesses. Slow crack growth, crack opening displacements and compliances were recorded. In addition to the test data, the report presents discussions on the residual strength "behaviour, the thickness effect, R-curves and COD and compliance measurements

Method of producing a weldable and ageable aluminium alloy of great strength and product

Abstract: The invention provides a weldable and heat-treatable aluminium alloy which comprises from 4.5 to 5.8% zinc, from 1.0 to 1.8% magnesium, from 0.10 to 0.30% zirconium, from 0 to 0.30% iron, from 0 to 0.15% silicon, from 0 to 0.25% manganese, less than 0.05% of each of other elements, the sum of these other elements not exceeding 0.15%, and the balance aluminium, which alloy comprises metastable precipitates of zirconium aluminide uniformly distributed in a number greater than 1010 per mm3, and of a particle size less than 2,000A.

Method of making aluminium bearing alloy strip

Abstract: An aluminium-lead bearing alloy, optionally containing tin, silicon, copper and cadmium, is produced in strip form by spraying droplets of the molten metal onto a substrate under conditions such that they strike the substrate in a highly undercooled condition and are chilled to solidification at the substrate at the rate of at least 103 DEG C/second so as to precipitate the lead in the form of a fine dispersion of separate particles. The deposit of solidified droplets is then subjected to compaction. A surface layer of commercial purity aluminium or other suitable aluminium alloy may be applied to one or both surfaces of the aluminium-lead alloy strip to facilitate the production of a composite bearing alloy- steel strip by a roll-bonding procedure.

Porous concrete prodn - using ground slag obtd from aluminium alloy melting as gas - generating agent

Abstract: Gas-generating agent for porous concrete mfr. is produced by using slag formed as waste prod. in the melting of Al alloys, and grinding the sepd. 0.3-1.2 mm grain-size fraction which contains =70% metal particles. Regenerated Al alloy slag waste may be used. Chlorides are washed out of the sepd. fraction with water, used in an amount such as to maintain a near neutral medium, and dried before grinding. Before grinding, the slag fraction may be mixed with pourable abrasion material, e.g. quartz sand. Admixture with sand accelerates grinding to desired fineness and allows formation of 2-5 mu pellets.

Aluminium alloy rivet stock heat treatment - to avoid time-dependency of rivetting properties

Abstract: Alloy is compsn. : 3.1-8.0 (5.1-6.1)% Zn, 1.5-3.5 (2.1-2.9)% Mg, 0.5-2.5 (1.2-2.0)% Cu, bal. Al and pref. also 0.18-0.3% Cr, 0.0-0.3% Mn, =0.5% Si, =0.7% Fe and =0.2% Ti (wholly or partially replaceable by Zr), is soln. treated quenched, then aged 24-72 (40-60) hrs. at 110-130 (115-125) degrees C, followed by 3-20 (6-20) hrs. at 140-200 (160-175) degrees C. This gives the props. : shear strength >29 (pref. >=30) kp/mm2, upsettability >44 (esp. >=61)%, and insensitivity to stress corrosion.

Violet gold-aluminium alloy - deposn by flame or plasma flame spray-gun welding

Abstract: Depositing a decorative layer of violet Au-Al alloy e.g. AuAl2 contg. 78.5% Au and 21.5% Al, on an article is effected by flame- or flame plasma spray-gun projecting the alloy powder. Alloy may be flame-sprayed directly on surface, which is pref. roughened to improve adhesion of coating, or on to an inter. metallic anchoring layer, e.g. Ni aluminide, preliminarily deposited by flame- or flame plasma-spraying, electrolytically or by vacuum-evapn. Process is partic. useful for coating an 18 (14) carat au alloy object with a violet Au alloy layer of 18 (14) carat, e.g. obtd. by mixing AuAl2 with Au, Al or another metal.

Aluminium alloy rounds - with low beryllium content for guaranteed surface oxide film thickness

Abstract: The rounds are of Al alloy of compsn 2-4% Mg, 02-03% Mn, bal Al and are initially formed from material contg is not >000003% Be Used for multistage drawing to hollow cylinders, eg spinning bobbins, and an oxide layer, acting as lubricant support, of 0006-0010 mm thickness can be guaranteed after annealing

Workable aluminium alloy - having predetermined electrical conductivity and tensile strength

Abstract: An Al alloy having predetermined electrical conductivity and T.S. by charging a furnace with relatively pure Al and scrap Al alloys contg. one or more of Cu, Fe, Si, Ti, B, V, Cr, Mn, Ga, Zn and Mg. Blending is carried out in such a way that the element constituents (other than Al) fall within the ranges given by the formula: 8(% Cu + %FE) + 20(%Si) + 90(%Ti + %V + % Cr + %Mn) +2 (% Ga + %Zn) + 25 (%Mg) = x - y + (16000-T)1000 (where x is 64.9, y represents the predetermined electrical conductivity and is 61.9 - 62.5 and T represents the predetermined T.S. and is 12000 - 27000 p.s.i.).

Light alloy piston - with friction welded base of sintered, dispersion hardened aluminium alloy

Abstract: The piston comprises a body made of a conventional alloy friction welded to a base, made powder metallurgically, from a heat resistant, dispersion-hardened aluminium alloy which is free of oxide inclusions. The latter is esp. an extruded AlV2Si3, AlV4Si5 or AlCr5Si3 alloy contg. nitrides, silicides, borides or carbides of transition metals. The base has improved short term tensile strength, creep resistance and toughness.

Manufacturing Exercise Involved in the Redesign of the Hawker Siddeley Trident (Tri-Jet) Fuselage

Abstract: The purpose of certain design studies was to examine the application of titanium construction to replace existing aluminium alloy structure using the same design loadings, applying the same structural philosophies, and accepting the same practical constraints on geometry. Under these design conditions weight savings result from the relative specific material properties of titanium alloys and aluminium alloy, the reduction in sizes permissible in titanium and, also from the exploitation of the weldability of titanium to produce more efficient configurations. Ti 8A1, 1Mo, 1V was specified (Duplex Annealed). The relatively thin fuselage skin (0.022 in.) was expected to be sufficiently free from stress corrosion hazards under aqueous conditions. Three particular areas were chosen for evaluation, viz., the sheet/stringer/frame structure in the keel area, the upper fuselage, and a window panel area. The usual attention was given to fatigue strength, critical crack length, and residual strength. Fusion welding was used whenever practicable, i.e., for skin to stringer joints and panel butt welds, with a little electrical resistance spot welding for the frame to fuselage skin attachment. The weight savings possible with the titanium design as compared with the aluminium structure were as follows: Fuselage keel area – 26.3% Upper fuselage area – 17.6% Window panel area – 28.0% The overall weight saving on the complete fuselage section was 23.6%.