Experiments were carried out on manufacturing porous sintered aluminum with excellent sound of around absorbent, strength and corrosion resistance. From the view point on sound absorbent, it was found the porosity 37 to 43% is good for the absorption of sond frequency 500 to 2 kHz in the condition of air gap over 50mm. The more increase the Cu content in sintered Al, the more increase the strength and sintering becomes much easier. However, corrosion is accelarated by an increase of Cu content in the material. The be st way for the manufacturing of porous sintered aluminum is to add small amount of Cu in Al during sintering process and some cold rolling from the porosity of 53 to 40%.

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Lubricating oils containing such additives as 1% E. P. agents (tricresyl phosphate, dibenzyl disulfide and chlorinated paraffin) were tested. The limiting drawing ratio increases by the function of additives particularly tricresyl phosphate in lubricating oils at low drawing speed, but not so remarkably at high drawing speed. The surface on drawn cups is scratched to a greatest degree when the base oil (paraffinic mineral oil VG 32) and the oil containing dibenzyl disulfide are used at low drawing speed. The scratch is moderated by the use of oils containing tricresyl phosphate. The amount of metal transfer of worked materials onto the drawing die decreases with increasing the drawing speed and markedly decreases by the use of oils containing tricresyl phosphate at low drawing speed. Tricresyl phosphate in E. P. agents is the most effective in this work. Chlorinated paraffin has an intermediate effect between tricresyl phosphate and dibenzyl disulfide.

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Fluxless brazing was made in vacuum down to 2 × 10^-5 torr at 600°C for 3 mn using Al-10% Si-1%Mg filler alloys containing Bi up to 0.4% in the form of brazing sheet cladding. Fluxless brazing was also made in reduced nitrogen down to 10^-1 torr and in purified nitrogen at 760 torr using Al-10%Si filler alloys containing Bi up to 0.4%. An addition of Bi particularly 0.05 to 0.1% to brazing sheet claddings improves the length of filled clearance and leg length ratio in all the brazing processes. Although the flow factor is unchanged, the fillet form is homogenized by the usie of Bi bearing brazing sheets. Bi freely exists in Al-10%Si filler alloys, while it combines with Mg in Al-10% Si-1%Mg filler alloys. The mechanism of improving the brazability by Bi addition in vacuum brazing processes is attributed to that Mg and Bi or Bi vaporize at low temperatures breaking down the surface oxide film on brazing sheets, and Mg and Bi prevent reoxidation of the fresh surface produced during heating by gettering oxygen in the brazing furnace.

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Temperature rise of extruding shapes is attributed to the conversion of kinetic energy of extrusion into heat. Using differential equations and the finite element method, a study was carried out to calculate the heat generated and its flow during extrusion of aluminum alloys with respect to the billet, die and container. A relationship between extrusion speed and the temperature elevation within extrusions is obtained.

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Cutting resistance, cutting temperature, cut surface roughness, tool wear, chip treating and others of free cutting aluminum alloy 2011-T3 and 2011-T8, high strength alloy 2017-T4, 5056 alloys having different compositions and anticorrosive free cutting alloys G67-T6 and G67-T8 were examined in wet cutting comparing with ones in dry cutting. Those of a free cutting brass and a free cutting steel were also tasted.
2011 alloys are excellent in machinability especially in cutting resistance and the chip treating. G67 alloys have early the same turning machinability as 2011 with the exception of low speed dry cutting. All the 5056 alloys have nearly the machinability a little better than 2017 which has poor machinability. 5056 alloys have poor machinability in heavy duty dry cutting, but are improved the machi nability especially the cutting resistance, cut surface roughness and chip treating in wet cutting. Cutting oil No. 23 is slight superior to machine oil No. 22.

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