Ironing formability of hard aluminum, 1100, 3004 and 5052 sheets was studied. O-temper is prefered to hard temper to ensure a large ironing ratio in single stage ironing. While, hard temper such as H18 is prefered to H2-temper or O-temper, in the tandem stage ironing. These facts are related to the quantity of work hardening before ironing and to the strain hardening coefficient n-vaiue. Intermetailic compounds reduce built-up on a die and reduce friction stress. 3004 alloy is preferable to 1100 or 5052 for ironing. Ironing stress has a minimum value to a half die angle. The lublicating condition has influence to the minimum point. The optimum half die angle for 3004-H18 is about 10°.

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2017 alloys naturally aged, artifically aged and annealed were friction welded using a brake type friction welding machine. The fatigue strength of the specimens notched at the weld interface is nearly the same regardless of the preheat treatment, lower than that of the naturally aged base metal, and higher than that of the artificially aged and annealed base metals. Naturally aged friction welded joints notched at 1 to 5 mm from the weld interface are higher than those notched at the weld interface and slightly higher than the base metal in fatigue strength. Both the specimens notched at 15 mm from the weld interface and notched at the weld interface have nearly the same fatigue strength slightly inferior to that of the base metal.

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Compression tests were made at-196 to 200°C using specimens from 5083-o sheets in the longitudinal, long transverse and short transverse directions. Stress-strain curves slightly change in accordance with the cutting direction. The compressed surface takes on an elliptical shape. α (= b/a) value (ratio of lengths of the minor axis (b) to the major axis (a) on the elliptical cross section of the middle of specimens during compressive testing) depends on the specimens and on test temperature to a great degree. Specimens in the LT direction have the highest value and ones in the L direction have the lowest, α is the value showing anisotropy of specimens.

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Electrical conductivities of MgCl₂-ACl (A = Li, Na, K and Cs) binary melts were measured at temperature from liquidus to 1200K by AC bridge method. Molar conductivities show negative deviations from the additivitity. The deviation increases as the radius of alkali cation in ACl increases from Li⁺ to Cs⁺. The maximum negative deviation is found at the composition of about XACl = 2/3. Apparent activation energies for electrical conduction at XACl = 2/3 increase with an increase in radius of alkali cation and are closely related to the interaction parameter derived from heat of mixing of MgCl2-ACl binary melts. The electrical conductivity of MgCl2-ACl binary melt is greatly affected by complex formation of MgCl42-, because transport of other ions is prevented by MgCl42- of large size and low mobility.

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condensation behaviors of gaseous aluminum chloride were examined on the bases of such factors as flowing velocity of gaseous aluminum chloride into a condenser, velocity of fluidizing gas into the condenser and temperature distribution in the condenser. Aluminum chloride power is continuously recovered with prolonged time at a rate about 0.15 to 0.18 g/mn. The effective recovery of aluminum chloride powder is increased about 25% by adding solid aluminum powder into the condenser. The optimum conditions for producing aluminum chloride powder are achieved by simultaneous control of the flowing velocity of gaseous aluminum chloride and the velocity of fluidizing gas into the condenser. If the former is faster than the latter, gaseous aluminum chloride adheres to the condenser wall. The characteristics of aluminum chloride powder recovered are; average diameter about 74 μm, apparent specific gravity 0.64 g/cm³ and angle of repose about 41°.

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Galvanostatic anodic dissolution in chloride solutions at the current density of 0.11 mA/cm² was proposed to estimate intergranular corrosion susceptibility of aluminum alloys and applied to such alloys as Al-Mn, Al-Zn-Mg, Al-Si and Al-Mg-Si. Preferential dissolution of grain boundary in the alloys after particular heat treatments was easily recognized in the test. The dissolution characteristics were agreed well with those of immersion corrosion test in tap water. Furthermore, intergranular corrosion mechanisms were discussed in terms of dissolution and anodic polarization characteristics.

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