Showing papers on "Aluminium alloy published in 1979"

Piston and cylinder assemblies

Abstract: In a piston and cylinder assembly in which the piston is made of an aluminium alloy, the wall of the cylinder contacted by the piston is formed of a hyper-eutectic silicon aluminium alloy having the composition by weight percentages of silicon (Si) 12-20%; copper (Cu) 0.5-5%; iron (Fe) 1.0-6%; magnesium (Mg) 0.2-2%; nickel (Ni) 0.5-4%; and optionally manganese (Mn) 0-5%; cobalt (Co) 0-3%; chromium (Cr) 0-3%; tin (Sn) 0-8%; titanium (Ti) 0-0.3%; lead (Pb) 0-5%; and molybdenum (Mo) 0-5%, the remainder being aluminium.

Compositions and processes for coating aluminium

Abstract: The corrosion resistance and paint adhesion of aluminium and its alloys is improved by contacting the aluminium (or aluminium alloy) surface with an aqueous acid solution containing polyacrylic acid or an ester thereof and at least one of H 2 ZrF 6 , H 2 TiF 6 and H 2 SiF 6 , the pH of the solution being less than 3.5. The waste disposal problems associated with conventional chromate phosphate coating processes are avoided. The coating solution may be replenished with a concentrate containing polyacrylic acid or an ester thereof, at least one of H 2 ZrF 6 , H 2 TiF 6 and H 2 SiF 6 , and a source of free fluoride, preferably hydrofluoric acid, to complex dissolved aluminium.

Electric throughflow heater for water, oil etc. - has aluminium component with flow bores and parallel grooves for tubular heating elements

Abstract: The heater has an aluminium or aluminium alloy extrusion cast component defining a flow channel for the fluid to be heated and an elongate groove (5) parallel to this channel, in which the heating device is positioned. The flow channel comprises one or more large dia elongate bores (2) while the heating device comprises one or more aluminium coated tubular heating elements. The aluminium component may have two parallel flow bores (2) with an end cap fitted to one end of it and the adjacent dividing wall between the bores (2) removed, so that the flow is directed from one bore to the other. Pref. two grooves (5) each containing a heating element are provided on both sides of the aluminium component along the centre line between the two bores.

Penetration behaviour of a high-strength aluminium alloy

Abstract: The ballistic penetration behaviour of a high-strength aluminium alloy, 7001 T6, was investigated and targets of the alloy were found to fail in two modes, discing or plugging, depending on the orientation of the target in relation to the extrusion direction of the round bar from which it was cut. The dependence of failure mode on orientation was related to poor fracture toughness in planes containing intermetallic stringers which were aligned parallel to the extrusion direction. A model for discing failure was developed which allows the penetration resistance of the plates to be calculated from the target strength properties. It is possible to prevent both the discing and the plugging failure modes by the use of steel back-up plates in contact with the rear of the target.

Exfoliation corrosion mechanisms in the 7020 aluminium alloy

Abstract: The first necessary condition for the occurrence of exfoliation corrosion is the existence of a fibrous texture Transgranular exfoliation corrosion, which can be observed in some instances, develops through grains in which recrystallization is incomplete and which exhibit a substructure with remnants of a fibrous structure As with intergranular corrosion, the controlling parameter is the formation of continuous anodic zones In the case of exfoliation corrosion, these anodic zones are localized in planes parallel to the „fabrication orientation” In the case of the welded 7020-T 6 alloy, two types of exfoliation corrosion have been observed, depending upon the nature of the anodic zones: The first type is related to the main elements, magnesium and zinc, which precipitate in the grain boundaries as large anodic MgZn2 particles during a short reheat (welding) at 200° – 250°C The second type is related to the secondary elements, chromium and/or manganese It is hypothesized that the precipitation of particle layers, reported by ADENIS, depletes the neighbouring solid solution, thus making it anodic with respect to the rest of the metal The exfoliation corrosion develops by anodic attack of the following alloys in the T4 condition: For the phenomenon to occur without galvanic current, in addition to chromium or manganese, it is necessary to have iron which depassivates the cathodic reaction and zinc in solid solution (T 4) which lowers, by about 100 m V, the anodic zones potential The influence of zinc becomes nul when it is precipitated (T 6)

Aluminium alloy cylinder and manufacturing method thereof

Abstract: An aluminium alloy cylinder includes a cylinder body and a cylinder bore therein An iron layer is electrodeposited on the wall surface of the cylinder bore by means of a high cathode current density so that a multiplicity of randomly oriented channels are formed in the electrodeposited iron layer

Light alloy piston for IC engine - has hard wearing surface layer of aluminium oxide deposited electrolytically

Abstract: The piston is made of aluminium or aluminium alloy. It has a crown (1) and a cylindrical side (2) with grooves (3) for piston rings. The skirt below the rings has bearings (4) for a gudge on pin which carries the connecting rod (5). The surfaces of the crown, cylindrical side and grooves are covered with a hard wear resisting layer. This layer consists of aliminium oxide obtained by an iodisation. A specialised electrolytic process gives an extremely this surface layer which is hard and wear resisting and is firmly bonded to the parent metal of the piston. Alternatively a thermal spray process can give a thicker layer.

Heat treating continuously cast and rolled aluminium alloy strip - consists of annealing to obtain good combination of strength and deep drawing properties

Abstract: The strip or sheet is made on a belt casting machine, and contains 05-30% Mn, together with >=1 of is not >05% Zr, 01-1% Fe, 01-06% Si, is not >03% Cu, is not >3% Mg, and is not >02% Cr The strip or sheet is heated 5 mins to 24 hrs at 300-454 degrees C The heat may be carried out (1) after casting and before rolling; (2) after hot rolling; (3) after casting and cold rolling; or (4) after hot- and cold-rolling A fine grain size is obtd in the annealed condition which prevents the formation of "orange peel" effects in deep drawing; but a high yield point is reached after further cold work

Effect of thermomechanical treatment on structure and properties of 2036 aluminium alloy

Abstract: The effect of thermomechanical treatment (TMT) on the structures, precipitation behaviour, and mechanical properties of commercial-grade aluminium 2036 alloy has been investigated. In both the solutiontreated and aged and the TM-treated conditions, the main strengthening phase was observed to be θ′ Prestraining of the material accelerates the precipitation of θ′-phase and reduces the ageing time required to achieve maximum strength. By raising the temperature of deformation, the distribution of dislocations changes from cellular to uniform and also causes a finer and more uniform distribution of θ′-precipitates. The combined effect of uniform dislocation and θ′-precipitate distribution results in increased strength without any significant loss in ductility.

Aluminium alloy foil for condenser and method of producing same

Abstract: Improved aluminum alloys are disclosed which are particularly useful as foil material in electrical capacitors. These alloys may contain either titanium in an aluminum base or a titanium and boron mixture in an aluminum base. The particular combination of titanium and boron presents a greater increase in capacitance in foil formed from this alloy than the increase in capacitance due to titanium or boron alone. Particular processing of such alloys is also disclosed.

Production of rolled products

Abstract: A composite metal sheet or plate is manufactured by completely immersing an assembly of parallel or substantially parallel metal core sheets in molten metal at a lower melting point than the metal of the core sheets, and after the molten metal has solidified reducing the thickness of the ingot by hot rolling in a direction generally normal to the planes of the core sheets. The method has a particularly useful but by no means exclusive application in the production of reinforced aluminium alloy sheets and plates.

Process of manufacturing a dimensionally stable anode

Abstract: 1. A process for manufacturing an anodic electrode, stable in dimensions, of the type comprising a core made of electroconducting material and an electrocatalytic conducting coating, characterized in that an electroconducting core is firstly made from a common metal melting at high temperature, such as iron, an iron alloy, aluminium, an aluminium alloy, copper, a copper alloy, said core is then introduced into a first molten high temperature electrolytic bath constituted by a mixture of alkali metal chlorides and of chlorides of valve metals, to form a first conducting coating on the core, said core provided with its first coating is then introduced into a second electrolytic bath comprising noble metals, to form a second electrocatalytic conducting coating on the core provided with its first conducting coating.

Porous metal agglomerates

Abstract: The invention is concerned with porous metal agglomerates suitable for use in metal fuels and consisting of combustible powders of nodular, flaky, irregular or acicular shape and preferably a mixture of aluminium and silicon although aluminium, aluminium alloy or aluminium mixed with silicon, magnesium or iron or alloys of these metals can be used. The powder is of 0 to 500 microns size range or a cut thereof and is granulated with a synthetic resin binder by build-up to a porous agglomerate having a size range of 100 to 2500 microns and an apparent density of between 0,4 and 1,1.

Aluminium alloy for casting

Abstract: PURPOSE:To provide an aluminium alloy with a higher strength and thoughness and a less secular change by adding Mg and Mn to Al in a proper proportion while limiting the composition ratio of harmful elements therein

Coloration of aluminium using chromium complex salt dye

Abstract: PURPOSE: To obtain a highly dark black-colored aluminium which is excellent in fire resistance, heat resistance, bleeding resistance upon sealing hole, etc., by coloring an anodic oxidation treated aluminium with a 1:2 type chromium complex salt having a specific structure. CONSTITUTION: An anodic oxidation treated aluminium is dipped in an aqueous solution of a complex salt dye (e.g., the compound of the formula II) of the formula I (where X⊕ is H, Na, K or NH 4 ion and the substitution position of NH 2 group is 4- or 7-position of naphthol) for coloration. The coloration can be performed in a temperature range from room temperature to boiling point but particularly preferably temperature is 40W70°C, and also the preferable pH of the immersion bath is 4.5W7.5. The aluminium used includes, besides pure aluminium, ones capable of being treated by anodic oxidation with an aluminium alloy, e.g., Al-Mg, Al-Si, Al-Mg-Si, etc. COPYRIGHT: (C)1980,JPO&Japio

Dynamic Strength of Ti-Alloys and Al-Alloys

Abstract: Continuous compression tests and incremental strain rate change tests of four kinds of titanium alloys and four kinds of aluminium alloys are carried out within the strain rate range of 10–4 ∿103/s and the temperature range of -195°∿50°C. The experimental results reveal the effects of the strain rate and the temperature on the flow stress at 5% strain. The strain rate sensitivity obtained by the continuous tests or the incremental tests is also revealed. The thermal and the athermal components of stress are presumed and the relation between the activation volume and the thermal component of stress is discussed.

Method of anodising aluminium, novel article with an anodised aluminium surface, and use thereof in alkaline conditions

Abstract: In order to improve the resistance to staining by alkaline media of anodised aluminium prepared in a conventional acid electrolyte, the aluminium (including aluminium alloy) article is first anodised in borate electrolyte before being anodised in acid electrolyte.

Cylinder drum for axial piston machine - has steel or aluminium cylinders with antifriction internal bronze layer

Abstract: The cylinder drum for an axial piston machine sleeve is coated with low friction material to provide high thermal stability above 250 deg.C. The sleeve (6) is made of steel and the thin antifriction layer of bronze. The low friction coating thickness is 1.5% of the bore dia. The cylinder drum (1) can also be made of pref. aluminium alloy for reducing weight.

Inhibition of the Corrosion of Grey Cast Iron in Ethanediol/Water Solutions by Benzoate/Benzotriazole Mixture: A Synergistic Effect

Abstract: The synergistic effects of sodium benzoate and benzotriazole in inhibiting the corrosion of grey cast iron in 50% ethanediol/water solutions are described. Good inhibition can be obtained in the presence of both inhibitors at concentrations of eachwhich are ineffective when either inhibitor is present alone. The results also showthat the inhibitors are effective on both ‘as-cast’ and machined surfaces. Limited information is presented to demonstrate a similar synergistic effect for the inhibition of corrosion of an aluminium alloy. Some possible adsorption mechanisms to explain these effects are considered briefly.

Porous sintered aluminium (alloy) body - produced by liq. phase sintering of different aluminium alloy powders

Abstract: A nove porous body consists of a fired body of Al (alloy) powder of rod, needle, oval or other irregular shape and having interconnected pores in amt 33-50 vol% The body is produced by (a) mixing Al (alloy) powder (I) with a powder (II) of an Al alloy of >=10 degrees C lower mpt, (b) moulding the mixt to the required shape in the absence of pressure and (c) sintering at a temp >=10 degrees C below the mpt of the Al (alloy) powder (I) but above the mpt of powder (II) The body is useful as an acoustic installation material (eg to absorb high frequency sound from high speed electric vehicles) or as a fluid filter The liq phase sintering technique allows highly porous sintered Al (alloy) bodies, having high corrosion and heat resistance and mechanical strength, to be produced

The behaviour of boron-aluminium composites during and after impact

Abstract: The behaviour of two types of aluminium alloy (1200 and 2024) reinforced unidirectionally by boron fibres has been studied and the effect of an impact on the residual properties and under fatigue conditions determined. Spherical and cylindrical indenters have been used over a range of speeds covering six orders of magnitude. It is found that the fibres fail due to bending induced by the impact, but that the matrix surrounding the breaks is not necessarily cracked. The tensile strengths of impacted specimens have been compared to strengths of similar specimens containing a partial surface notch, simulating the impact damage, and good agreement found. Impacted specimens have been tested in circular bending fatigue on a machine which has been developed so as to maintain the maximum applied load constant despite any change of specimen compliance. The matrix bridge is quickly broken under cyclic loading and the B-2024 specimens show signs of progressive fibre damage. TheS-N curve for the B-1200 specimen is much flatter due to the inability of the softer matrix to transmit high stresses to fibres neighbouring fibre breaks. The residual tensile strength of impacted boronaluminium is found to depend on the remaining intact fibres and not on the matrix. In fatigue the notch effect produced by the damage zone is reduced at long lifetimes as cracking of the matrix parallel to the fibres isolate the damaged region.

Corrosion resitant aluminium alloy with moderate strength and excellence in extrusion workability

Abstract: PURPOSE:To provide an Al alloy with excellence in extrusion workability and a proper strength which permits use for structure through addition of Zn to an Al-Mg-Si alloy.