The basic characteristics of wringing torque were analyzed in the previous report. This time we have experimentally confirmed the effects on wringing torque of surface roughness, flatness, etc. of the wringing surfaces of block gauges, and studied on whether or not industrial use can be made of the newly defined wringing torque. The results are summarized as follows :
1. Deducing from the measurements of wringing torque, the thickness of oil film is about equal to 1/2 of the sum of the surface roughnesses of the block gauges wrung together.
2. The thickness of oil film in the best wringing conditions is assumed to be on the order of 0.02 μ.
3. It believably is possible to evaluate wringing torque by means of wringing force.

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In this paper, the application of ultrasonic pulse method to the fine grain size grinding wheel is studied.
The results obtained are as follows :
1. Elastic modulus reflects the structure of the fine-grain-size grinding wheel.
2. Elastic modulus has the linear relation with the bending strength of the fine-grain-size grinding wheel.
3. The grade of the fine grain size grinding wheel can be estimated by the elastic modulus as well as the ordinary grinding wheel.
4. Elastic modulus has the relation with Rockwell hardness, as well.

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This paper reveals the mechanism of crater wear of carbide cutting tool at high cutting speed range which is analyzed using Electron Probe Micro Analyzer. The findings are as follows; (1) The crater wear of the carbide cutting tool is able to classify into following two types, first, the wear which predominates at higher cutting speed and produces fine wear particles, the cause of this type would be attributed to the thermal adhesion between the tool and the chip materials, second is the wear which predominates at lower cutting speed and produces relatively large wear particles. (2) The cause of the latter type of the wear is attributed to the break down of the built-up edge and the “belag”, in this paper, this type of the wear is called “tear by sticking matter”. (3) The volume of the crater wear which is presumed from the density of the wear particles which is detected on the chip surface using EPMA coincides with the measured value at low cutting speed, hence, a new method for rapid tool life testing is proposed.

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Steels containing Tellurium are generally used for free cutting steels of precision engineering parts. But the effect of Tellurium on mechanical properties of these materials are not well known yet. This paper deals with the influence of Tellurium on fatigue strength. And rotating bending fatigue tests were carried out using specimens containing MnS, FeS, MnTetype inclusions and containing substantially no inclusions respectively. And these tests were run in order to resolve some of the problems involved in evaluating machined surface layer for a given residual stress and work hardened layer by on endurance limit was discussed.
Main results obtained are as follows :
(1) Endurance limit of Tellurium free cutting steel was high order compared with the based steel and Sulphur free cuttting steel. And the endurance limit were arranged in ascending order as follows.
Sulphur free cutting steel <Based steel <Tellurium free cutting steel
(2) Endurance limit by the existance of machined surface layer were high stress level 5-8 kg/mm² compared with no machined surface layer.
(3) At some stress amplitude, residual stress of machined surface of Sulphur free cutting steel and based steel was reduced almost to zero at the number of cycles about N=10₃. On the other hand, residual stress of machined surface of Tellurium free cutting steel decrease gradually after the number of cycles about N=10₃.
(4) The decrease of the hardness in the work hardened layer of Sulphur free cutting steel and based steel is observed within the range at the number of cycles about N=010₃ But the decreasing rate of it for Tellurium free cutting steel were relatively small compared with the other specimens.
(5) It seems that the inclusions FeS, MnS shows a promoting type for crack propagation, and the inclusion MnTe shows a controlling type for it. And effect of FeS, MnS, MnTe on crack propagation could be estimated from disorder of striation around inclusions.

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A simulation method for the estimation of cutting tool life is proposed in the present paper, which involves the process : collection of data from tool life experiments, statistical data processing and Monte Carlo simulation using these data.
It is revealed by this simulation method that the distribution of cutting tool life which is observed in production line can he estimated from laboratory scale experiments with sufficient accuracy. The advantage of the present method is based on the extraction of probabilistic information from a tool wear curve, not from the distribution of tool lives which requires the repetition of wear experiment. Then a process planner troubled by lack of data can design a process with high accuracy. And the present method derivates confidence limits upon V-T diagram from as small amount of data as possible. Such V-T diagram is more effective for practical use by adding confidence limits on curves which indicate the tool life with its statistical features, necessary for optimum design of production lines.

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In order to study the relation between the friction-trace and the surface damage produced in the course of stick-slip caused by a conical diamond scriber sliding on 18-8 stainless steel, the surface asperities and the deformation in abraded superficial layers were examined by replica method of electron microscopy and by transmission electron microscopy respectively. The main results obtained are as follows.
Marks like cracks curved convexly to the scratched direction were observed at the bottom of grooves. And the mean path between the marks was consistent approximately with the mean sliding one during a slip obtained from the friction-trace.
Pile-ups and tangles of dislocations, deformation twins and s-phase martensites were observed in plastically deformed regions produced by scratching with a scriber. But a-phase martensite was not observed in crystallites.

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The origins of surface roughness are studied during the finish turning of 0.45% carbon steel with a carbide tool. The existence of micro built-up-edge, the profile of chip surface and machined surface, and the wear grooves on the minor flank of the tool are measured at some interval during the test run. The primary origin of surface roughness changes with tool wear in the order of i) micro built-up-edge, ii) wear groove and rarely existing micro built-up-edge, iii) wear groove and self-excited vibration of tool. Small surface roughness (R_max=1.5 μ) is produced between the stage ii) and iii) when a machine tool having high dynamic stiffness is used.
At the statge of stationary tool wear rate, the transcription of wear groove of tool to the work surface plays main roles in the surface roughness formation. Therefore it is duely expected that the surface with small surface roughness can be produced by turning under the condition which does not produce deep groove wear.

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Wear process of coated abrasives is reported both theoretically and experimentally. A structural model of coated abrasives is proposed, in which the grains are distributed uniformly on the belt surface, while the normal distribution is assumed for the height of the grain of conical shape. The wear process is simulated by the Monte Carlo method by means of digital computer. The simulation describes well the wear process of coated abrasives in terms of density of effective cutting edges, distribution of area of wear land of each cutting edge and total area of the wear lands. The wear process is determined by the following factors; wear rate of grains, standard deviation of the longitudinal diameter of grains, conical angle of the modeled grain, grain concentration, belt length, belt width, normal load applied to the belt, belt speed and contact length between the belt and the workpiece.

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This paper describes the design and performance of a torsional vibration pickup which has been newly developed for measurements of the transmission errors of gears. The pickup described consists of a seismic inertia suspended between two units of cross-spring pivots, a differential transformer, an eddy-current damping device, and a slip-ring assembly, and has the following characteristics; size 130 φ 182 mm : weight 3.2 kg : natural frquency 1 Hz or 0.62 Hz : fraction of critical damping 0.55.
The variation of natural frequency, one of the principal disadvantages of the pickups currently used for the above-mentioned applications, can be eliminated by placing the center of gravity of the seismic inertia at the mid-point of the axis of rotation of the seismic system and by mounting the pivots in such a way that each unit of pivot is in the opposed angular position. The theory and practical performance limit of the elimination of this disadvantage is discussed, together with the static angular rotation of seismic inertia resulting from the elastic deformation of pivot caused by the weight of seismic inertia.

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The contour lines of anticlastic surface of aluminium, steel and glass plates deformed by simple bending were observed as interference fringes of hyperbolas in holographic interferometry. The contour lines, when superposed with similar ones shifted longitudinally or laterally, produce Moire patterns whose fringe pitches are in proportion to radii of longitudinal or lateral curvature respectively.
Then it can be checked by uniformity of the pitches whether the plate is bent symmetrically or not and when the plate is bent symmetrically the radii of curvature could be measured. Poisson's ratio is equal to the ratio of lateral curvature to longitudinal one and can be also calculated from the angle between asymptotes of hyperbolas. It is found that the values of Poisson's ratio obtained in these two cases agree well. But they are found a little smaller because of the effect that the plate, of which width is much larger than thickness, tend to bend cylindrically. The values become closer to the reasonable values of Poisson's ratio when the ratio of width to thickness becomes smaller.
Young's modulus can be also obtained from the proportionality of the longitudinal curvature to the bending moment.

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