Molten AC4C alloy was poured at different temperatures in the die cavity in which a SUS 304 steel insert preliminarily dipped in AC4C bath had been placed and was pressed at 320kg/cm². The hydrostatic pressure applied to a poured metal allows a condition suitable for bonding of a casting to the coating layer. The poured metal and the insert should be kept at temperatures above the liquidus of the former until pressing to ensure successful bonding. The chill layer resulted from lower pouring temperature and the oxide film on the coating metal reduce the pressure effect, because fine defects align surrounding the insert.

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Stress relaxation tests were carried out in the region of steady state deformation at temperatures 623, 673 and 723K. The stress relaxation rate is proportional to the stress in the short period from beginning of the relaxation and subsequently to third power of the stress. The internal stress and the mobile dislocation density can be estimated on the basis of stress relaxation curves in the region in which the stress relaxation rate is proportional to the stress. The internal stress obtained in the relaxation test is in accordance with that in the dip test. The mobile dislocation density depends on the steady state stress and is expressed as: ρ_mα(σ_s/μ)²

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Al-Si alloys containing Si 4 to 20% were solidified in a permanent mold under hydraulic pressure up to 3000kgf/cm². The impact strength at elevated temperatures is lowered in the alloys containing more of silicon. The impact strength particularly of hypoeutectic alloys is heightened in accordance with temperatures significantly above 300°C. The hypoeutectic squeeze castings allow width spread beneath the notch particularly at elevated temperatures. Both the hypoeutectic and eutectic squeeze castings show a ductile fracture on which dimples are found. The hypereutectic squeeze castings usually show a cleavage fracture. The alloys soliaified under atmospheric pressure show a cleavage fracture regardless of silicon contents and temperatures.

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Al-3.5%Cu-0.07%Ti(B) alloy to which Mg, Zn, Mn, Cr and Si were added was studied. Ultimate and yield strength of the Al-Cu-0.07%Ti (B) alloy rapidly increase with increase in Cu 2 to 5%. The elongation and Charpy impact value rapidly decrease with Cu up to 3.5%. The Al-3.5%Cu-0.07%Ti(B) alloy containing 0.3%Mn, 0.2%Cr and 0.2%Si has mechanical properties considerably increased. Ultimate and yield strengths of the Al-3.5%Cu-0.3%Mn-0.2%Cr-0.2%Si-0.07%Ti(B) alloy exponentially increase with Mg up to 1.5%, but the elongation and Charpy impact value decrease. Zn in the alloy gradually intensifies the strength. The alloy containing 3.5%Cu, 1%Mg, %Zn, 0.3%Mn, 0.2%Cr, 0.2%Si and 0.07%Ti(B) is recommended which have tensile strength 42kg/mm² and elongation 18% (permanent mold cast and T6).

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Twenty Al-Fe-Ni alloys were unidirectionally solidified at temperature gradients G=60 to 70°C/cm and solidification rates R=15 to 100μm/s. The coupled growth regions of monovariant Al-T (ternary compound) eutectics were determined. Cellular eutectics are formed in the coupled growth region except at extremely slow rates of solidification. The shape of the eutectics transforms from elongated to square cell in accordance with solidification rates. Excess Ni affects to occurance of constitutional undercooling, because formation of cell structures depends on experimental Ni/Fe and G/R ratios. The X-ray diffraction and EDS analysis show a ternary FeNiAl₉ compound as described by Bradley et al., although wide ranges of Fe and Ni contents are permitted. The T-phase is usually rod-like and transforms to ribbon-type at slow solidification rates. The interphase spacing λ changes in accordance with Rλ²=225μm³/s.

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Microhardness and tension tests at room and elevated temperatures were carried out on Al-T (ternary compound) regular eutectic alloys in the coupled growth region. The eutectics are hardened linearly in proportion to λ^-1 (λ: interphase spacing) and: Fe+Ni%. The tenslie strength at room temperature depends on the microstructure and volume fraction of fibers. The maximum strength is 31kg/mm². The non-cellular rod-like eutectic has a modulus of elasticity of fibers E_f=12700kg/mm² and strength σ_f=240kg/mm². The Al-T eutectic is stronger than the Al-NiAl₃ eutectic and has a more stable fiber-matrix interface at 200° to 500°C. The Al-T eutectic in which rod-like regular eutectics are easily grown has strength equivalent to that of the Al-NiAl₃ eutectic. It is further available for composite materials than Al-FeAl₆.

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