The aluminum corner of Al-Si-Sr ternary alloy system was investigated by means of inverse rate thermal analysis, identification by X-ray diffraction, EPMA analysis and microscopic observation.
A ternary compound SrAl₂Si₂, named "T", exists in this ternary system and Al-T line is considered as a quasibinary system with a eutectic point at 1.1%Si, 2.4%Sr, 645°C. The aluminium corner is divided into two regions by the Al-T quasibinary system. A ternary eutectic point was determined to locate at 575°C, 13.1%Si, 0.03% Sr, which is very close to the Al-Si binary eutectic point. The modification effect of small amount of strontium addition on Al-Si alloys can be regarded to be due to the formation of fine ternary eutectic structure. In the Al-SrAl₄-T region, a ternary eutectic point was found to locate at 643°C with 1.7%Si, 2.4%Sr.

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The effectiveness of hydrogen fluxing on removal of inclusions in an aluminum melt has been studied. Based on the scheduled conditions, hydrogen gas was blown into the melt through an alumina tube whose tip had been filled up with porous alumina. The effect of the luxing treatment was evaluated by optical microscope observation for the electropolished surface of the sample which represents the melt.
Oxide particles in the melt are removed effectively by hydrogen fluxing. While significant increase in hydrogen content of the melt is accompanied by hydrogen fluxing. Directional solidification of the melt treated with hydrogen attains both the removal of oxide and the low level of hydrogen content.

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The relationship between stress corrosion and applied potential has been investigated in 1M NaCl solution by using 2017 aluminum alloy with various aging structure.
Potentiostatic stress corrosion test showed that corrosion form (roughness general corrosion, uniform general corrosion, pitting corrosion, intergranular corrosion) was depend on the applied potential and it was separated in four potential regions. The similar tendency could be seen in any aging structure. The critical potential of region that intergranular corrosion occured in was in the vicinity of pitting potential of each aging specimen. Cathodic polarization curves under stress showed the limiting current. From this result, it was considered that intergranular corrosion is governed by cathode, and the reduction of dissolved oxygen plays an important part in cathodic reaction of this alloy.

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Effect of additional elements such as Fe, Si, Mn, Cr, Ti and B on dry cutting tool wear of Al-4.5%Mg alloy was studied.
The results are obtained as follows: (1) With the least amount addition of Ti and B to the alloy, the material, which contains very hard intermetallic compound such as TiB₂, increases cutting tool wear resulted by abrasion. (2) Tool wear decreases as Fe content increases to the level of 0.2% and it gradually increases above 0.2%. The reason is that, when Fe content increases and, as a result, solute Fe content increases, it decreases greatly the diffusive tool wear between the adhesive layer of aluminum alloy and tool whereas the Al-Fe compounds increase as Fe content increases, resulting in the increase in the abrasive tool wear.

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Pitting corrosion has been observed around intermetallic compounds on aluminum alloys. In order to obtain the relationship between the microscopic pitting corrosion and the composition of intermetallic compounds, Al-0.6%Fe alloys which contains silicon ranging from 0.09% to 1.51% were investigated by means of electrochemical measurements and metallographic observations. The additional effects of silicon to Al-Fe alloys have been presented in increasing of cathodic polarization resistance with an increase in the Si/Fe ratio in the intermetallic compounds. The most frequent occurences of microscopic pitting corrosion were discussed. Pitting corrosion was supposed to break at the boundary of intermetallic compound which has the lowest Si/Fe ratio and aluminum matrix which has the lowest impurity content.

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As a working method of cold forging, the side extrusion working by a piercing punch was applied to a cylindrical specimen of 99.5% aluminum and cup-shaped products were tried to produce. In this study, effect of the pre-annealing and intermediate annealing on side extrusion working was studied.
The working methods are as follows. (1) One end of the cylindrical specimen is pressed by flat end punch. (2) Secondly it is piercied by a conical punch into the specimen. In this study, two processes were applied. In process A, the specimen was heat-treated before pressing by the flat end punch and in process B, it was heat-treated before piercing by the conical punch. In case of high pressed products being worked again, process B was studied to prevent the crack occurance and the skin roughing in the products. For different working process, the shape and the surface of the deformed head, and the results of hardness and plastic flow on the radial section of the deformed head were compared and studied. The results obtained are as follows. (1) As soon as the specimen contacts with the side of the circular die, it is excluded rearward. (2) Process A is superior to process B on the rate fulled materials in the circular die. (3) Process A is intence on the skin roughing phenomena of the surface of the deformed head.

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