Takuichi Morinaga

Studies on casting Hydronalium (2nd Report):On the non-heat treatment aluminium-magnesium alloy contain zinc

It is well recognized that 10% Hydronalium alloy reveals the highest mechanical properties among the sand casting aluminium alloys after appropriate solution heat treatment. But sound castings and higher mechanical properties are expected only by best foundry practices and adquate heat treatments.In the first place, in order to clarify the effect of maximum heating temperature and casting temperature on the final mechanical properties, the molten metal was cast at various tempreatures in heating cycle to maximum tempereature as well as in cooling. The mechanical properties scarcely vary owing to the maximum melting temperature.To obtain the best properties of 10 per cent Hydronalium, temperature of solution heat treatment becomes essential, which bring β phase (Al3Mg2 or Al8Mg5), Mg2Si and Al3Fe compounds into single α solid solution. So it becomes necessary for us to definite the crystal structure of β phase itself to investigate the process of heat treatment.After surveying X-ray diffraction patterns of polycrystalline β phase, the authors confirmed that the β phase was f.c.c. lattice with very large lattice parameter, and it was also revealed that the atomic arrangement of the phase fluctuates by trace impurities.As homogenization during solution heat treatment is considered to be affected by the temperature and time of holding, dilatometric test, X-ray analysis and optical microscopic observation have been carried out in order to confirm above effects (during solution heat treatments).In the course of solution treatment, contraction of the specimen was observed, which seems to explain the disintegration of β phase into α solid solution. The higher the temperature, the more rapid the shrinkage proceed, however, volume change is not complated until after 30 hours. Moreover, we have performed supplemental experiments to investigate the effect of magnesium content, time of holding and cooling media (air, boiling water) on the mechanical properties, and on corrosion resistance.The addition of a large quantity of magnesium improves tensile strength though elongation decreases greatly, when magnesium content exceed 12 per cent, the mechanical properties found to be rather unstable. Quenching in boiling water developed better results than air cooling.

On the ear in the deep drawing of aluminium alloy sheet. (1st Report)

Continuing the previous report on 3S, the cold rolled 52S sheet, the manufacturing conditions after hot rolling process of slab, i. e. the direction of cold rolling, the cold reduction and the annealing temperature, are pursued on effect to the directionality of sheet. The results are summaeized as follows:(1) In this experiment, the ear by deep drawing of 52S sheet is 0°-or 90°-ear in all.(2) The ear is less than 2% notwithstanding annealing temperature, and this extent of ear is out of question for the using die in production process.(3) There is not so distinguish difference between the one-way-cold (unidirectional) rolled sheet and the cross way rolled one.(4) It is not consistent to the previous results that the directionality by means of Knoop ratio is in closed connection with the ear in deep drawing.

On the resistance of aluminized steel in high temperature water

Due to its high anti-corrosion properties under room temperature and also to its high thermal resistance, the applications of aluminized steel has remarkably been increased in recent time. On its resistance to corrosion in high temperature water, however, no study has so far been made. If its high resistance in high temperature water is proved, it is well considered that the aluminized steel will get more promissible as a material for boilers, vessels for some chemicals and others.In this connection, by use of aluminized steel plates which have deferent chemical compositions, an experiment has been made for studying on their resistance to corrosion in high temderature (250°C) distilled and city water respectively by way of measuring the degree of corrosion, electrode potential, X-ray diffraction and so on.The findings are as follows:1) The degree of corrosion in primary stage is different according to the chemical composition of base steel.2) The corrosion resistance of the material in the distilled water at 245°C is little different from that in the city water at same temperature.3) The corrosion film formed on the surface of the material is mostly composed of Bohmite (α-Al2O3·H2O), but Diaspore(β-Al2O3·H2O) is also formed a little both in distilled and city water at the temperature of 245°C.

On the adding effect of the condensed phosphate on the anti-corrosive property of 1S

As reported in our previous paper, the condensed phosphate is usable as an adding agent to improve the anti-corrosion properties of aluminium alloys in wine and brandy. In salt water, however, this material does not show any effect, though it thows slight effect under wet-and-dry corrosion test with salt water.Even in wine and brandy, in case they are treated by ion-exchange-resin, the abovementioned effect by condensed phosphate can not be shown so remarkably.This time, the said effect was examined by use of acetic acid solution to find out whether the sealing property of metal is distinguished by the complex chemical reaction between be agent and the compositions or it is displayed by the simple acid solution itself, and also to obtain the finding on the particular characteristics of the condensed phosphate as an adding agent to wine, brandy and some other foods for improving anti-corrosion property of aluminium alloys.

On the utilization of aluminium and its alloys in the wine and brandy industry (12th Report)

The anti-corrosive effect of the film on aluminium sheet, produced by the chemical treatments such as MBV process and alodine process, to white wine was reported on in the previous report. This is the report on the same effect to red wine which attacks aluminium quite hard.It was found that the protective film thus produced was attacked by the red wine in long time but the corrosion was not very severe, so that it would be quite possible to find out the way of utilizing aluminium in red wine industry, if some more improvement could be done in this process in future.

On the utilization of aluminium and its alloys in the wine and brandy industry. (8th Report)

It is already known from the study on anti-corrosive property of aluminium alloys against wines that the alloy is seriously attacked by wines. To materialize the practical use of aluminium in wine industry, it is essential to make such special treatment as, for example, protection of alloys by making cirtain film on its surface, development of new alloy with strong anti-corrosive property, use of agent to be added into wined for stopping the corrosive reaction of win, etc.This is a report on the experiment on the effect of anti-corrosive property of surface treatment to aluminium alloy against white wine, which has been continuously carried out for one year.The applied surface treatment methods are “Alumilite”, the “MBV” and the “Alodine”. In each method, the protictive film was attacked by white wine, when the material was kept touched for long time. But, in case of “Alodine” and “MBV” methods, the corrosion was not so hard as in the “Alumilite” method. The flaver and palate were deteriolated particularily in the “Alodine” method.By this prelimeinary testing, hovever, it was found that the Alumilite method and MBV method could be possible to be utilized in practice, if some improvement is developed for them in future.

On the utilization of aluminium and its alloys in the wine and brandy industry (9th Report)

In the previous time, the report was made on the result of preliminary test of anti-corrosive effect against white-wine of “Alumirite” film, formed under anode oxidation treatment by use of sulphuric acid. To obtain the further referencial data for the utilization of aluminium alloys in wine industry, the subsequent test was made on the anti-corrosive effect against brandy, which severely attacks aluminium alloys, of the film formed on the surface of aluminium sheet under anode oxidation treatment with mixed solution of sulphuric and oxalic acids. In the same time, the anti-corrosive effect of the surface treatment in case of the treatment being imperfectly made, (namely, approximately 1.78 percent of the surface being exposed to the air) and also the influence of the base materials (1S and 2S) to the anti-corrosive property of the film were tested.

On the utilization of aluminium and its alloys in the wine and brandy industry(6th Report)

Anti-corrosion properties of aluminium alloys such as 1S, 2S, 3S and 52S, which are generally used as anti-corrosive materials, were examined by use of such wines an brandy, baking sherry, white and red dry wine.It was found that each of them was more or less attacked by wines. The corrosion was especially appeared when the brandy was used and the palate and flavour of the brandy was remarkably made worse. The conclusion was thus made that aluminium alloys are not adequate to be utelized in wine industry at lest under present circumstance.This is to report on the charactaristics of corrosion resistance of aluminium alloys in sumary and the proposed counter-plan of how to utilize these alloys in wine andbrandy industries.

On the utilization of aluminium and its alloys in the wine and brandy industry

The corrosion tests of the aluminium alloys, 1S, 2S, 3S and 52S which have been used for the anti-corrosion materials, are made in the white dry wine, and their characteristics of anti-corrosion property in the wine are researched.The aluminium alloys are attacked by the white dry wine, but the reactions are very slow compaired with those in the brandy. 3S and 52S which showed good resistance to the attack of brandy are pronounced largely by the wine, and 1S and 2S which show poor resistance to the attack of brandy are not much affected.The total acidity in the wine seems almost unchanged notwithstanding the hours of dipping the alloy, but the wine increases its pH-value and grows worse in its flavor and taste and on this occasion the wine becomes muddily white (after about 40 days) and then becomes clear again (after about 90-120 days), but in some cases the colour of wine fades.We add that this research owes its expence to the Grant-in-aid of the Scholarship of the Institute of Light Metal Foundation.

Some experiment on the aging of Al-Cu alloy by means of specific volume analysis

The authors repoted previously that the specific volume analysis could be applied to the industrial method for analysing the aging mechanism in aluminium alloys. In this paper, details of the experimental study are reported as a continuation of previous report, on the aging of three sorts of Al-Cu alloy, i. e. 3.116% Cu, 4.240% Cu and 6.200 Cu, the internal change of which was investigated well by H. K. Hardy and others, by means of specific volume analysis.The experiments are pursued just like those in the previous report, that is, after being kept at 500-520°C for 30 minutes, the specimens are quenched in water and recieve the temperd aging for a long time at the prescribed temperature, and then the change of specific volume is pursued. And further the specific volume analyses are applied on the aging at raised temperature of the quenched specimens and the aging (at 20°C) of the rehardened specimens which are quenched into water from 200°C.We appreciate that this research has been done at the expence of the Grant-in-aid of the Scholarship from the Institute of Light Metal Foundation.