微視的に見た材料の加工面性状について
圧縮加工中における材料の潤滑挙動(第2報)
1970 年 36 巻 431 号 p. 808-813
詳細
1970 年 36 巻 431 号 p. 808-813
On the basis of the study made in the deformation process with respect to the behaviours of friction and lubrication and also the micro-structure of metals, a new lubrication system has been proposed here. The behaviour of the metal can be observed by means of the light-etching method on the pre-deformed metal surface. The action of retained lubricants in the metal-tool-interface is due to the hydrostatic effect in the microscopic surface pockets of a work piece which are all formed due to several types of mechanism.
In type 1 where metal as aluminium, it resulted from asperities in different orientation of grains and the slip-band.
In type 2 where brass and carbon steel as metal, it resulted from the hollow pit between the convexed second phase (e.g, β-phase or pearlite) and the slip-band.
In type 3 where bearing steel as metal, it resulted from asperities to be associated with the different orientation of grains and also from the micro-cavities between carbides which are all dispersed finely and uniformly.
The low coefficient of friction which was observed in a smaller grain size seems to be from the fact that, a large amount of pit-space occupied by the surface pockets were finely continued with the fine slip-band in these pockets.
