Showing papers on "Aluminium alloy published in 1985"
TL;DR: In this article, a production method has been developed in which the application of pressure ensures very low porosity levels and strong fibre-matrix bonding, but the virtual absence of any chemical reaction at the interface.
Abstract: Composites formed by infiltration of an array of fine alumina fibres with aluminium alloy melts have been investigated in terms of fabrication characteristics, microstructural features and mechanical properties. A production method has been developed in which the application of pressure ensures very low porosity levels and strong fibre-matrix bonding. Details of the transport phenomena occurring during fabrication have been explored with a view to optimizing selection of applied pressure, thermal fields, alloy composition and the structure of the fibrous preform. Microstructural examinations revealed an intimate fibre-matrix bond, but the virtual absence of any chemical reaction at the interface. Comparison of property measurements with data from unreinforced alloys revealed increased elastic moduli and marked improvement in tensile strength at elevated temperature, accompanied by reductions in elongation.
166 citations
01 Apr 1985
TL;DR: In this paper, the strength and energy absorption of single lap joints with four epoxy adhesives and three aluminium alloy adherements were measured using an instrumented impact test, and the results showed that the strength of the single lap joint was increased with the amount of energy absorbed.
Abstract: Using an instrumented impact test, the strength and energy absorption of bonded single lap joints have been measured for single lap joints with four epoxy adhesives and three aluminium alloy adhere...
79 citations
TL;DR: In this paper, the chemistry of typical compounds of epoxy and phenolic resins on various anodized aluminium surfaces was studied by Fourier Transform infrared spectroscopy, and it was found that resols and epoxynovolak form strong complex compounds with the oxide on the aluminium surface and that dicyandiamide is partially hydrolyzed to guanylurea.
47 citations
TL;DR: In this article, a porous preform of semi-random short alumina fibres with liquid aluminium alloys, using squeeze-casting techniques, was used to produce sound castings.
44 citations
TL;DR: In this article, the influence of surface pretreatments and alloy compositions on the chemical compositions of adherend surfaces is discussed and correlations between the durability and X-ray photoelectron spectroscopy data are discussed.
39 citations
TL;DR: Incorporation de fibres de carbone a haut module without traitement de surface dans des matrices en alliages Al−Mg, Al−Ca and Al−Cu par moulage forgeage.
Abstract: Incorporation de fibres de carbone a haut module sans traitement de surface dans des matrices en alliages Al−Mg, Al−Ca et Al−Cu par moulage forgeage Etude de l'interaction chimique entre matrice et fibre, et de son effet sur la resistance du composite et la morphologie des fractures
35 citations
TL;DR: In this paper, the authors showed that hydrogen embrittlement is the rate determining step for stress corrosion cracking (SCC) of welded 7020 and postweld artificially aged.
27 citations
Patent•
02 Apr 1985TL;DR: A process for ion-nibbling aluminium or an aluminium alloy as an article to be treated, in which the article is disposed in a sealed vessel, the oxygen gas in the vessel is removed, the surface of the article was heated to a prescribed nitriding temperature; the surface was activated to facilitate the formation of an aluminium nitride layer by the subsequent ion-nitriding treatment; and thereafter the article were subjected to ion-riding, thereby forming an aluminium oxide layer having excellent wear resistance and high hardness as discussed by the authors.
Abstract: A process for ion nitriding aluminium or an aluminium alloy as an article to be treated, in which: the article is disposed in a sealed vessel; the oxygen gas in the vessel is removed; the surface of the article is heated to a prescribed nitriding temperature; the surface of the article is activated to facilitate the formation of an aluminium nitride layer by the subsequent nitriding treatment; and thereafter the article is subjected to ion nitriding, thereby forming an aluminium nitride layer having excellent wear resistance and high hardness. This ion nitriding treatment for aluminium material can be carried out even at temperatures lower than a solution treatment temperature of aluminium material.
26 citations
TL;DR: In this article, the fracture toughness of high strength aluminium alloy 7075-T6 in the as-cast condition was studied using standard compact tension specimens with thicknesses ranging from 4 to 25 mm with a 3 mm incremental interval.
24 citations
Patent•
04 Apr 1985
TL;DR: In this paper, a printing aluminum alloy material plate is described which provides good printing characteristics, that is, surface treatment ability, burning ability, and ink stain resistivity; the plate is obtained from an aluminum Alloy material which is cold-rolled at a reduction rate of from 20 to 95% after being subjected to intermediate annealing at a temperature of 300° to 550° C.
Abstract: A printing aluminum alloy material plate is described which provides good printing characteristics, that is, surface-treatment ability, burning ability and ink stain resistivity; the plate is obtained from an aluminum alloy material which is cold-rolled at a reduction rate of from 20 to 95% after being subjected to intermediate annealing at a temperature of 300° to 550° C wherein the aluminum alloy material comprises 025 wt % or less Si, from 005 to 10 wt % Fe, 003 wt % or less Cu, 010 wt % or less Ti, and 003 wt % or less Mg and the balance of unavoidable impurities and Al
22 citations
TL;DR: In this article, the effect of grain boundary precipitation on the stability of extrinsic grain boundary dislocations was studied in alloys in which the occurence of depletion of definite alloy elements in grain boundary region is well documented, namely Cr-Ni-austenitic steel and Al-Zn-Mg alloy.
TL;DR: In this paper, the application of the new developed internal standard method to charged-particle activation analysis, simultaneous determination of Ti, Cr, Fe, Cu, Ga, Ga and Zr in several commercial aluminium alloys has been tried using the respective proton-induced reactions.
Abstract: In order to study the application of the new developed internal standard method to charged-particle activation analysis, simultaneous determination of Ti, Cr, Fe, Cu, Ga and Zr in several commercial aluminium alloys has been tried using the respective proton-induced reactions. As a result, it could be proved that the best precision and accuracy are also obtained in these determinations.
Patent•
06 Jul 1985TL;DR: Aluminium alloys for producing ultrafine-grained powder having improved mechanical and micro-structural properties are based on the systems Al/Cu, Al/Ni, Ni, Y, Ce, Mo, Cu, Cs, Rb, Sr, Zr, Ti or B.
Abstract: Aluminium alloys for producing ultrafine-grained powder having improved mechanical and microstructural properties are based on the systems Al/Cu, Al/Ni, Al/Cu/Mg or Al/Fe with additions of Fe, Co, Ni, Y, Ce, Mo, Cu, Cs, Rb, Sr, Zr, Ti or B, which form phases - in particular intermetallic compounds - which, due to a very high cooling rate (order of magnitude 10 DEG C/second) are used for precipitation hardening and/or dispersion hardening of the matrix. Using powders of a particle diameter of 20 mu m on average, Vickers hardnesses of 185 ... 260 ... 360 units are achieved, depending on the alloy.
TL;DR: In this paper, Fatigue propagation tests on artificial short cracks (initial length ˜ 0.15 mm) were performed in vacuum and in nitrogen containing small traces of water vapour (3 ppm) on a high strength aluminium alloy type 7075 in two aged conditions (T651 and T7351) at a load ratio of 0.1 and a frequency of 35 Hz.
Abstract: Fatigue propagation tests on artificial short cracks (initial length ˜ 0.15 mm) were performed in vacuum and in nitrogen containing small traces of water vapour (˜ 3 ppm) on a high strength aluminium alloy type 7075 in two aged conditions (T651 and T7351) at a load ratio of 0.1 and a frequency of 35 Hz. A predominant influence of environment was determined for short crack growth. This behaviour has been discussed in terms of crack growth rate versus the effective stress intensity factor range relationship previously determined for long cracks. The results obtained suggest the absence of closure at the early stage of short crack growth with an enhanced environmental influence as compared to long crack behaviour at the same load ratio. As the crack grows the effect of closure increases progressively and the short crack effect disappears after a crack growth of the order of 1 mm.
Patent•
28 May 1985
TL;DR: A piston is formed in two parts (10, 11). The main part (10) is formed by gravity die casting from aluminium or aluminium alloy and a second part (11) of the piston was formed by a squeeze casting process to produce a material which is stronger and more resistant than the gravity die cast aluminium alloy as discussed by the authors.
Abstract: A piston is formed in two parts (10, 11). The main part (10) is formed by gravity die casting from aluminium or aluminium alloy and a second part (11) of the piston is formed by a squeeze casting process to produce a material which is stronger and more resistant than the gravity die cast aluminium alloy. At least one piston ring groove (14a) is formed in the second part (11). The two parts are then electron beam welded together to form the complete piston. The squeeze cast portion may be reinforced with whiskers or fibers to further improve its properties. This method of construction has the benefit that only the minimum amount of the piston is formed by the more expensive and time- consuming squeeze casting process so that parts of the piston which do not require the improved properties given by squeeze casting are simply gravity die cast. This is of particular benefit in large diesel pistons.
TL;DR: In this article, it was found that corrosion of the Al-0.2% Ga and Al- 0.2%, Ga-0% P alloy is controlled not only by the alloying elements, but also by intermetallic compounds (insoluble in the matrix) which contain alloying element and impurities (Fe) present in technically pure aluminium.
Abstract: In order to cause shifting of the potential in the negative direction and to simultaneously control dissolution in sodium chloride solutions, aluminium alloys utilized as anodes in electrochemical power sources contain small additions of alloying elements. This can be achieved with highly pure aluminium alloys. The binary Al-0.2% Ga alloy made of high purity aluminium has a high negative potential (−1570 mV at 10 mA cm−2), but also a high corrosion rate. The addition of 0.2% P to the above alloy decreases corrosion. Impurities present in technically pure aluminium considerably affect the anodic and corrosion behaviour of the investigated alloys. It was found that corrosion of the Al-0.2% Ga and Al-0.2% Ga-0.2% P is controlled not only by the alloying elements, but also by intermetallic compounds (insoluble in the matrix) which contain alloying elements and impurities (Fe) present in technically pure aluminium.
TL;DR: The role of homogenization temperature in making the serrations appear indicates that the uniqueness of the precipitation kinetics in AlZn alloys is of importance as discussed by the authors.
TL;DR: An amorphous aluminium oxide coating, generated from aluminium chelate or alkoxide compounds, has been investigated as a primer for adhesively bonded phosphoric acid anodized 2024 aluminium adherends.
TL;DR: The presence of fine striations (0.2−0.4 μm spacing) on fracture surfaces of aluminium alloy 7075-T651 produced by stress corrosion cracking in air and in 3.5% NaCl solution indicate that the stress corrosion crack advances by small discrete crack jumps as mentioned in this paper.
TL;DR: In this article, the effect of cold rolling and annealing on the earing behavior of aluminium alloy 3004 was investigated by X-ray diffraction and it was observed that an increase in the difference between the (422 and (200) Xray intensities in the rolling plane is correlated with 45° earing.
TL;DR: In this paper, the structure of composite particles formed in an Al-Li-Cu-Mg-Zr alloy has been investigated using microscopical techniques, and evidence is given that substantial diffusion of lithium into the core particle does not occur.
Abstract: The structure of composite particles formed in an Al-Li-Cu-Mg-Zr alloy has been investigated using microscopical techniques. A discussion of the observed contrast of these particles is presented, and evidence is given that substantial diffusion of lithium into the core particle does not occur.
TL;DR: In this article, a good correlation was obtained for d a d N and ΔKeff using the Schijve6 equation for U.S. sheet material with different formulas for Δ keff as a function of stress ratio R.
Patent•
26 Apr 1985
TL;DR: An aluminium alloy support for a lithographic printing plate, suitable for an electrochemical roughening treatment and excellent in fatigue resistace, heat softening resistance and printability, is provided in this article.
Abstract: An aluminium alloy support for a lithographic printing plate, suitable for an electrochemical roughening treatment and excellent in fatigue resistace, heat softening resistance and printability, is provided which comprises aluminium and contains 0.05 to 1 % by weight of Mn, not more than 0.2% by weight of Si, not more than 0.5% by weight of Fe and unavoidable traces of impurities.
31 Jan 1985
TL;DR: In this article, the effects of cladding and anodising on flight simulation fatigue of notched specimens and riveted lap joints of 2024-T3 and 7475-T761 aluminium alloy sheet were investigated.
Abstract: The effects of cladding and anodising on flight simulation (gust spectrum) fatigue of notched specimens and riveted lap joints of 2024-T3 and 7475-T761 aluminium alloy sheet were investigated. Stress levels were chosen to provide long life data for bare alloy specimens. Cladding and anodising had very large effects on the fatigue lives. Cladding and anodising were always detrimental for notched specimens. For lap joints cladding was detrimental only in combination with anodising. Anodlsing was very beneficial for lap joints to be assembled from bare alloy sheets. With equivalent surface treatments 2024-T3 specimens always had longer average fatigue lives than 7475-T761 specimens.
TL;DR: In this article, the internal friction and elastic modulus of dilute Al alloys have been measured after fast neutron irradiation at about 5 K. The internal friction spectra and their annealing behavior in these alloys demonstrate that the configuration of their interstitial-solute atom complex seems to be different to each other and the main complex is immobile until stage III.
Abstract: Internal friction and elastic modulus of dilute Al alloys have been measured after fast neutron irradiation at about 5 K. The internal friction spectra in Al-Pb, Al-Si, Al-Zn, Al-Ag, Al-Sn and Al-In are very similar. This result suggests that the configuration of the interstitial-solute atom complex in these alloys is very similar. In Al-Mg, the main complexes have the configuration with nearly symmetry, but its internal friction spectrum is different from that of the above-mentioned alloys. The internal friction spectra and their annealing behavior in Al-Be, Al-Mn, Al-Fe and Al-Cu demonstrate that the configuration of their interstitial-solute atom complex seems to be different to each other and the main complex in these alloys is immobile until stage III.
Patent•
05 Dec 1985
TL;DR: In this paper, a piston body consisting of an aluminium alloy and a surface layer composed of an FeCrAl alloy was manufactured by first producing the surface layer by means of thermal spraying in a mould, then applying a thin binding layer of Al and finally casting the actual piston body on top of the binding layer.
Abstract: The invention relates to a piston for internal combustion engines, with a piston body consisting of an aluminium alloy and a surface layer composed of an FeCrAl alloy. The piston is manufactured by first producing the surface layer by means of thermal spraying in a mould, then applying a thin binding layer of Al and finally casting the actual piston body on top of the binding layer.
TL;DR: In this paper, the authors used an experimental forming-limit diagram to predict the limit strain in a range of punching stretching tests after pre-strain and annealing, and the results indicated that this approach can be used to predict limit strains in multi-stage industrial forming operations.
Patent•
13 Feb 1985
TL;DR: In this article, a process for manufacturing shaped elements of vehicles starting from a cast body of said alloy, which is homogenized at 540-580 DEG C and then worked to obtain sheets (or the like), which are then subjected to a solution heat-treatment at 525-535 DEGC followed by hardening and natural ageing to state T4.
Abstract: Aluminium alloy for shaped elements of vehicles and the like, which comprises from 0.25 to 0.35% of Si, from 0.20 to 0.30% of Fe; from 0.85 to 1.1% of Mg, from 0.10 to 0.25% of Cu; other elements, as impurities, each below 0.1%, in the aggregate below 0.2%; the balance to 100% being Al. A process for manufacturing shaped elements of vehicles starting from a cast body of said alloy, which is homogenized at 540-580 DEG C and then worked to obtain sheets (or the like), which are then subjected to a solution heat-treatment at 525-535 DEG C followed by hardening and natural ageing to state T4; said sheets are then formed by means of dies to shaped elements, which, at last, are subjected to artificial ageing at 180-220 DEG C.