In order to make the effect of processing clear, Mg₉₆Zn₂Y₂ alloy ingot and machined chips were extruded at various extrusion conditions. Tensile yield strength of extruded bar from ingot and extrusion force were increased with decreasing extrusion temperature. Tensile yield strength and extrusion force was proportional to hardness of ingot that is measured at extrusion temperature. Increased hot hardness resulted in improved strength with increasing of the degree of work hardening and extrusion force. Improvement of the degree of work hardens was observed as crystal orientation by XRD. Meanwhile, strain hardening of machined chips plays a major role of strengthening at extruded bar from chips. Static recrystallization of chips at preheating causes randomization of crystal orientation and higher elongation of extruded bar from chips. Difference in recrystallization behavior between extrusion of ingot and chips, dynamic recrystallization at ingot extrusion and static recrystallization at chips extrusion, was due to difference of strength mechanism of extruded bar from ingot and chips.

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Joining technology of CP-Titanium, capable of providing precision joining, is industrially very useful; however, it still has some unsolved problems in continuous atmosphere brazing technology. In this study, commercial pure titanium was brazed with laminated brazing fillers by using a newly developed continuous type non-oxidizing atmosphere furnace. This new furnace, using inert gas without hydrogen, is capable of providing oxygen partial pressure equal to or lower than that available in a vacuum furnace at a regular atmospheric pressure. Excellent applicability and capability of the new furnace in commercial pure titanium brazing was concluded by a series of evaluations after brazing including microscopic observations of the joint interface, chemical analysis, and shear test.

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We studied the effects of alloying element on environmental-friendly anodizing onto various AZ series magnesium alloys. This process uses mainly phosphate solution without the need for deleterious materials such as heavy metals or fluoride. We also investigated the characteristics of the coatings formed, such as their structure, composition, and corrosion resistance. Anodized coatings became dense, as the aluminum content increased. X-ray diffraction analysis revealed that the anodized coatings onto magnesium substrate containing aluminum concentration from 1 to 9 mass% had a glass-like structure. The formation of this structure is explained in terms of the film composition and freezing point. In salt spray tests, the anticorrosive performance of these coatings having an average thickness of 10 μm was changed, depending on the aluminum content, and the anticorrosive performance was improved with the increase in aluminum content. The coating onto AZ91D magnesium alloy retained the anticorrosive performance over 1000 hours.

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SWAAT for 20 days has been carried out on brazing sheets of 1 mm thickness to estimate outside corrosion resistance on the material for aluminum heat exchanger applied at higher temperature. Maximum corrosion depth after the test decreased in brazing sheets both of Al–1%Mn alloy core and of Al–1%Mn–0.5%Si alloy core clad with Al–Si alloy filler while it increased in that of Al–1%Mn–0.5%Si–0.5%Cu alloy core, with increase of heat treatment time at 200°C after brazing. Marked intergranular corrosion in the core was observed in the latter alloy. On the other hand, general corrosion was observed in brazing sheets clad with filler alloy containing Zn, and the attack stopped at near interface between filler and core, independent of core alloys and of heat treatment time. Corrosion characteristics and attack depth on the sheets were discussed in terms of electrochemical properties of filler and core alloys.

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