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Volume 43, Issue 516
Displaying 1-13 of 13 articles from this issue
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[in Japanese], [in Japanese], [in Japanese]1977 Volume 43 Issue 516 Pages 1376-1381
Published: December 05, 1977
Released on J-STAGE: January 20, 2010
JOURNAL FREE ACCESSDownload PDF (2026K) -
Experimental Investigation on the Results of Theoretical Analysis of Steady Wear (In the Case of Copper)Jujiro KAGAMI, Kunio YAMADA, Nobuo TAKEDA, Teiji NAOI1977 Volume 43 Issue 516 Pages 1382-1388
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe experimental investigations were carried out with copper in regard to the results of theoretical analysis of steady wear which were introduced in 5th report. The main results obtained are as follows :
(1) In relatively low range of sliding velocity, wears were nearly proportional to sliding time, but increased abruptly in higher range.
(2) The wear rates Vl were minimized at critical sliding velocity vc and the relation between Vl and v agreed qualitatively with the results of theoretical analysis in 5th report. Assuming the activation energy Δf to be 25 kcal/mol, calculated value of vc was relatively close to that obtained experimentally.
(3) In this experiment, it was observed that at the end of initial wear the wear volumes per unit time of sliding considerably decreased and the inflection points appeared on the cumulative wear curves at this time.View full abstractDownload PDF (1335K) -
Relationship between Indenting Behaviour and Indented DepthKen HORII, Yasuyuki TOMODA, Tomoharu YAMADA1977 Volume 43 Issue 516 Pages 1389-1394
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe fundamental characteristics of three-dimensional indentation are gained under three primary assumptions founded in the case of two-dimensional indentation. An analysis of the indentation on the material with single surface film is derived from the relationship between the above-mentioned characteristics and the load-depth curve. Hence, the good agreement between the analysis and the experiment of the indentation depends upon adapting the representative strain, especially from the view point of the mean pressure and the plastically deformed region. The value of the hardness has a close relationship to the resisting stress near the surface of the indent. The three processes are obtained by indenting on the material with the plated film; in the first process, deformation only in the plated film; next, the obstruction of the deformation on the boundary; and lastly the total deformation. both in the plated film and In the substrate material. These experimental results are consistent with the theoretical indenting deformation.View full abstractDownload PDF (1485K) -
Frictional 'Properties and Abrasiveness of Lapping TapesKazuhisa MIYOSHI, Kyuichiro TANAKA, Yoshio FUWA, Tomokazu MURAYAMA1977 Volume 43 Issue 516 Pages 1395-1401
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSExperiments were made to study the frictional properties and abrasiveness of lapping tapes and a magnetic tape on two types of rubbing : a running tape against a rotating cylinder of Mn-Zn ferrite crystal, and a running tape against a rotating magnetic head made of ferrite at a high speed of approximately 11 m/s in a two heads helical scan type VTR. Coefficients of friction of tapes are generally independent of the normal load and the sliding speed. The coefficient of friction depends on the material of the abrasive used in tape, while it is independent of the size of abrasive. The coefficient of friction takes the value of approximately 0. 40, O. 30 and O. 24 in the cases of the 1000 and 2000 mesh alumina lapping tapes, the 2000 and 4000 mesh silicon carbide lapping tapes, and the VTR magnetic tape, respectively. In the repeated traversal of tapes, the frictional coefficient of lapping tapes decreases gradually and becomes a nearly constant value after several traversals. That of magnetic tape is, however, independent of the number of traversals. Stock removal of ferrite is proportional to the tape-lapping distance and the normal load applied by tape. The size of abrasive plays an important role on the stock removal rate and a small increase of the size of abrasive increases very much the stock removal rate.View full abstractDownload PDF (1355K) -
Formation Mechanism of the Grinding Cracks in the Martensite Steels (1st Report)Hiroshi EDA, Kozo KISHI1977 Volume 43 Issue 516 Pages 1402-1408
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe grinding cracks are frequently found in the medium and high carbon martensite steels such as Fe-C steels, bearing steels, Mo steels, Mn steels, Ni steels and Cr steels. We are decided to go back to the metal structure in the origin of the workpiece to observe the grinding cracks from metallographical standpoint. In this report, the first step of study is investigated the kern and origin of the grinding cracks in the martensite structure. The next step deals with the significance of existence for the grinding cracks of martensite impingement cracks and the shape or size of the minimum unit of it. A summary of the main results are shown below.
(1) The impingement cracks of martensite were observed the lenticular martensite in the many shape of it. And the impingement cracks were become frequently kern of grinding cracks.
(2) The combination of martensite's impingement cracks and grinding cracks were observed in many kinds of the workpiece.
(3) The generation of minimum unit size of grinding cracks are observed in the martensite crystal. And the length of it was shown very high frequency in the range of 4.0-5.0μm.
(4) The stain and impingement cracks of martensite is very high sensitivity of the notch effect or stress concentration.
(5) The generation of microcrack in γ-phase was not observed in the transformation from fcc to bct.View full abstractDownload PDF (8319K) -
On Forming Temperature and Effective HeatHideho TANAKA, Shun'ichi OKAMURA1977 Volume 43 Issue 516 Pages 1409-1414
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSIn Tube-end Spinning, “softening” of tube material with frictional heat generated at interface between die and tubular stock, is considered as the most important fundamental principle. And so, knowing about the forming temperature and effective heat to soften the tube material is required to discuss the formability for Tube-end Spinning. In this paper, the equation of mean temperature θm1 of material at forming portion, and effective heat Q1 which is available for softening tube material during the forming are formulated. The results are written as below.
(1) The mean temperature θm1 increases according to the increase of die revolution and decreases according to the increase of the feeding rate of tubular stock.
(2) Effective heat Q1 is proportional to the forming time and becomes larger according to die revolution increase, smaller according to feeding rate and die angle increase.
(3) Effective heat Q1 is about 20-40% of total heat, and the amount of heat flowing into die is largest among of heat losses.View full abstractDownload PDF (1000K) -
Wear Resisted Resin Bonded Diamond Wheel Grinding CharacteristicsShojiro MIYAKE, Junji WATANABE, Yoshiyuki UENO, Kanekichi TSURUTA1977 Volume 43 Issue 516 Pages 1415-1420
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSWhen ferrites used for magnetic recording heads are ground with resin bonded and fine grained diamond wheels, accuracies should be kept by lowering wheel wear and grinding residue caused by visco-elastic deformation of wheels. The fine grained diamond wheels were bonded by resin bond materials which were chosen from the standpoint of wear resistance, high temperature of thermal softening and low friction coefficient to ferrites. These wheels have been tested with respect to stock removal rate, wheel wear, grinding force and surface roughness. The results are as follows :
(1) Resin bonded wheels, including 6-12μm diamond abrasives, can grind ferrites without cracks in the worked surface.
(2) The wheel wear rate increases rapidly in the range over a certain stock removal rate, which corresponds to the change in the bond wear from micro-ploughing by chips or worked surface to adhesion or crushing, accompanied with thermal softening characterized by the thermal wear resistance test.
(3) The stock removal rate of wheels bonded by polyoxybenzoyl or thermosetting polyimide is approximately six times higher than that of phenolic resin bonded wheels.View full abstractDownload PDF (1044K) -
Tadashi TAKEMURA, Hiroshi ASADA1977 Volume 43 Issue 516 Pages 1421-1426
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSAn experimental investigation has been carried out on the chatter vibrations due to cutting force variations caused by the intermittent cutting and the periodic chip formation. In this paper turning experiments are carried out using a small tool-dynamometer of piezoelectric type attached to a cantilever-type structure which is assumed to vibrate only in the direction of the principal mode. The results obtained are as follows. (1) The amplitude of the forced chatter vibration induced by the intermittent cutting is not increased or decreased by the regenerative effect, irrespective of the direction of the principal mode. (2) In machining of the free-cutting brass and the austenitic stainless steel which create periodic chips, selfexcited chatter vibrations are induced in the cutting direction extremely. These vibrations are quite different from the regenerative chatter, and are induced because the period of the chip formation is controlled by the tool vibration.View full abstractDownload PDF (1329K) -
On Elastic ContactKen-ichi KAWAI1977 Volume 43 Issue 516 Pages 1427-1432
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSA theoretical approach is presented to the plane theory of rolling contact with friction. An analysis is given of elastic contact of two cylinders. A comparison is discussed between the elastic stress fields from this analysis and from the theory of Hertz contact problem. If two cylinders have the same material properties, the pressure distribution and the width of contact agree with those of Hertz contact. If they have not the same material properties, the pressure distribution, the width and the location of the contact region differ from those of Hertz contact, however, for practical purposes the latter can be used. On the other hand, because of friction the stress fields in elastic medium shift to the direction of the frictional stress. Accordingly the location, where the material may initially yield, shifts to the same direction and approaches closer to the surface than that of Hertz contact.View full abstractDownload PDF (994K) -
Characteristics of the Journal Bearing composed of Drill Tip and HoleYoshio HASEGAWA, Osamu HORIUCHI1977 Volume 43 Issue 516 Pages 1433-1439
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSThe drill tip in a hole is considered to be equivalent to the journal of an externally pressurized partial bearing. In this report, taking account of the bending of drill shank due to the cutting force and oil-film force, the equilibrium attitude of drill tip in the hole is simulated by digital computer, and then the bearing characteristic, especially the oil-film force is investigated. The simulation results correspond reasonably to the experimental results of the former reports within quantitative deviations of 20-30%. The bearing characteristics depend on the supply pressure of cutting fluid, the neck-skew of drill tip, the shank length, the viscosity of cutting fluid and the work speed. Such characteristics can explain the behavior of drill tip and the accuracy of holes clarified in the former reports.View full abstractDownload PDF (1233K) -
[in Japanese], [in Japanese]1977 Volume 43 Issue 516 Pages 1440-1442
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSDownload PDF (569K) -
[in Japanese]1977 Volume 43 Issue 516 Pages 1443-1448
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSDownload PDF (3791K) -
[in Japanese]1977 Volume 43 Issue 516 Pages 1449-1453
Published: December 05, 1977
Released on J-STAGE: July 23, 2009
JOURNAL FREE ACCESSDownload PDF (1208K)
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