For the purpose of investigating variation in cutting temperature between workpiece and tool during approximately orthogonal cutting, following experiments were conducted by tool-workpiece thermocouple method using cutting dynamometer for measuring cutting temperature and cutting force, simultaneously.
Cutting tests were carried out on 4 sorts of pure metals; i.e., aluminum (99.5% purity), copper (99.6%), magnesium (99.9%), and 0.25% carbon steel.
The following results were obtained.
(1) The measured values of cutting temperature in the above metals were arranged in ascending order as follows.
Mg_??_Al<Cu<Fe
(2) It was observed that cutting temperature rase with the increase of cutting speed or feed, but scarcely affected by depth of cut.
(3) Cutting temperatures of the above metals were proportional to their respective shearing stresses.
(4) The rising rates of cutting temperature in the above metals with respect to the increase of cutting speed or feed were arranged in descending order as follows.
With respect to cutting speed Mg>Cu>Al_??_Fe
With respect to feed Mg>Cu>Fe>Al

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For the study of variation in cutting temperatures by the measuring techniques in the previous report, cutting tests were conducted under the following conditions:
cutting speed 100-600m/min
feed 0.04-0.32mm/rev.
depth of cut 1mm, 3mm
The specimens used for the tests were billets of the following 7 sorts of commercial aluminum alloys.
2S, 11S, 17S, 56S, 63S, Lo-Ex, and Al-23%Si cast alloy
The following results were obtained.
(1) The highest temperature measured in the former alloys was 470°C (for 580m/min, 0.32mm/rev. and 3mm) in 56S, and the lowest was 320°C (for 560m/min, 0.32mm/rev., and 3mm) in 2S.
(2) The values of the temperature were arranged in descending order as follows.
56S>17S>11S>63S>2S
(3) The highest cutting temperatures in Al-23%Si alloy and Lo-Ex were about 480 and 410°C (both for 320m/min, 0.32mm/rev., and 1mm), respectively.
(4) The rising rates of cutting temperature in the above alloys with respect to the change of cutting speed or feed were arranged in descending order as follows.
With respect to cutting speed 11S>17S>63S_??_56S>2S
With respect to feed 11S_??_17S>56S>63S>2S
(5) Isothermal lines were experimentally determined by cutting temperatures measured in the above 7 sorts of commercial aluminum alloys.

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The effects of Si on recrystallization and age hardening of Al-Zr alloys were investigated. Effective times for precipitation heat treatment for ingot at 500°C in order to raise the recrystallization temperature of Al-Zr-Si alloys were determined.
In Al-Zr alloys containing no Si, nucleation of ZrAl₃ will readily appear owing to the slight distortion of Al lattice structure containing Zr, but growth of ZrAl₃ will be sluggish owing to the slow diffusion of Zr in Al. Age hardening of Al-Zr alloys containing Si occurs in the range of 300-500°C caused by the precipitation of Zr₅-Si₃, which may be due to the diffusion of Si in Al. Proper ageing treatment of Al-Zr-Si alloys is effective in raising the recrystallization temperature; however, overageing treatment of the same alloys is detrimental to the above effect.

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It was found that production of ears in deep drawing of rolled sheets depended upon directional properties of the sheets and the orange peel effect of cup depended upon the effects of additional elements and grain size. The directional properties of rolled sheets depended upon many factors such as additional elements, reduction ratio, intermediate annealing, final annealing, etc.
The authors investigated the relation between ears and orange peel effect or heat treatment on rolled 2S sheets containing magnesium.
The results obtained were summarized as follows.
(1) In the specimen containing 0.20% of Mg, grain size was larger and orange peel effect was observed. On the other hand, in the specimen containing 0.57% of Mg, the height of ears was less in both directions of 45° and 0-90°.
(2) In the specimen which had been treated and held for a long time at higher soaking temperature, ears had a tendency to be produced in 45° direction. On the contrary, in the specimen which had been treated and held for a shorter time at lower soaking temperature, it had a tendency of orange peel effect.
(3) In the specimen which had intermediately been annealed at higher draft in hot working (draft of 99.8%), higher cars were produced in 0-90° direction with orange peel effect. However, in the specimen which had not intermediately been annealed, ears produced in 45° direction were higher with no orange peel effect. These results corresponded well with those of pole figures.
(4) When the reduction ratio in cold working was larger, the ears produced in 45° direction were higher and when the reduction ratio was smaller, orange peel effect was observed.

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Cutting-off tests were conducted on 2S and 56S round bars of about 40mm in dia. by holding the tool bit nearly around the centre of turning lathe.
If the tool bit was siturated in the higher position than the axis of rotation of the worked piece, cutting resistance gradually decreased with the increase of the depth of cut. This was caused by the fact that the actual rake angle in cutting grew gradually larger than that angle of tool itself with the approach of the tool to the centre. If the tool was set in the lower position, the resistance would grow in reverse.
The cutting resistance was calculated in consideration of the fact that the actual rake angle was affected by the vertical position of the tool bit. Then, it was shown that the calculated values corresponded well with the experimental values.

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Cut-off turning tests were conducted on 3 sorts of alloys now under development based on Al-Zn-Mg system and 4 sorts of experimental alloys which had been prepared with different chemical compositions for the use of pressure die casting.
The principal results obtained were as follows.
(1) There were little differences in cutting resistance and roughness of cut-off surface among the 4 sorts of experimental alloys.
(2) When cutting oil was applied, the experimental alloys showed slightly higher cutting resistance because of their higher hardness than that of the alloys now under development. However, the experimental alloys showed higher cutting ratio and it would be believed that they had higher machinability in turning.
(3) In dry cutting, the experimental alloys had much higher machinability than the alloys now under development, except Alcan 432 alloy.

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