In this paper, wear mechanism of soft metals rubbed by hard metal is discussed by considering the adhesive term in frictional force and the effect of surface roughness. New expression for metal wear is obtained as follows
W_s^*=W/FL=kH/1+kH·β/τ
Where W; Metal Wear (mm³), F; Frictional Force (kg), L; Rubbing Distance (mm),
H; Maximum Height of Surface Roughness(μ), τ; Shear Strength of Soft Metals (kg/mm²), k, β; Constant value respectively.
Wear tests of many kinds of soft metal as copper, aluminum, lead and so on, to fresh carbon steel plate are carried out by varying load and surface roughness of steel plate. The results show good agreement with the above expression for metal wear.

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Free rolling friction is measured by means of the pendulum method. The rolling friction of the tempered steel over a certain hardness shows a constant value, while it markedly increase when the hardness is less than that value. The marked increase may be due to the plastic deformation at the contact area of the specimen and it is clarified that these difference between the tempered steel and un-tempered steel is due to the energyloss in the elastic deformation i. P. the hysteresis loss of the material.

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Compression bending is a new technique which forms precise bend parts. Principle of this technique is based on an expectation that compression applied to the lateral direction of bend part neutralizes the circumferencial stresses of it, and then reduces the amount of springback and allows more accurate springback allowances. This principle is confirmed by mathematical analysis and experiments. The first die for this technique is produced. By the use of this die compression bending is performed in one operation of conventional presses.

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Expressions of contact angle between tool and work surface, of impulsive load in machining and of penetrating depth of abrasive particles into the work surface were given from the analysis previously presented. By using experimental data the above mentioned factors are given numerically and also their correct relationship with the rate of material removal influenced by the variables involved in the machining process is obtained. The conclusions are as follows :
(1) The contact angle, which is an important factor to decide impulsive speed, usually has the value from 30° to 180° and the suitable value corresponding to the suitable static pressure lies between 70° and 130°.
(2) Machining load consists of damping mechanical resistance and restoring stiffness, and they must be considered separately in contact time and in noncontact time. The way of vibration depends on the state of four elements of machining load above mentioned. But the machining rate has little relationship with these factors.
(3) Penetrating depth of abrasive particles into the work surface has close relationship with machining rate. From this fact it can be explained why machining rate depends on the kind of works and the size of abrasive particles and why the most suitable static pressure on machining rate exists.

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