WO2006001149A1 - 転がり軸受 - Google Patents
転がり軸受 Download PDFInfo
- Publication number
- WO2006001149A1 WO2006001149A1 PCT/JP2005/009449 JP2005009449W WO2006001149A1 WO 2006001149 A1 WO2006001149 A1 WO 2006001149A1 JP 2005009449 W JP2005009449 W JP 2005009449W WO 2006001149 A1 WO2006001149 A1 WO 2006001149A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- rolling
- bearing
- test
- nitrogen
- value
- Prior art date
Links
- 238000005096 rolling process Methods 0.000 title claims abstract description 91
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 63
- 229910052757 nitrogen Inorganic materials 0.000 claims description 31
- 229910001566 austenite Inorganic materials 0.000 claims description 30
- 230000003746 surface roughness Effects 0.000 claims description 22
- 238000007373 indentation Methods 0.000 claims description 15
- 239000010410 layer Substances 0.000 claims description 15
- 239000013078 crystal Substances 0.000 claims description 11
- 239000002344 surface layer Substances 0.000 claims description 9
- 239000002245 particle Substances 0.000 claims description 4
- 238000012360 testing method Methods 0.000 description 61
- 239000000463 material Substances 0.000 description 29
- 230000000052 comparative effect Effects 0.000 description 26
- 238000010791 quenching Methods 0.000 description 26
- 230000000171 quenching effect Effects 0.000 description 26
- 238000005256 carbonitriding Methods 0.000 description 24
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 21
- 238000010438 heat treatment Methods 0.000 description 21
- 229910052739 hydrogen Inorganic materials 0.000 description 21
- 238000005259 measurement Methods 0.000 description 21
- 239000001257 hydrogen Substances 0.000 description 20
- 238000000034 method Methods 0.000 description 18
- 239000003921 oil Substances 0.000 description 18
- 230000035882 stress Effects 0.000 description 13
- 238000010586 diagram Methods 0.000 description 11
- 238000005461 lubrication Methods 0.000 description 11
- 230000003068 static effect Effects 0.000 description 10
- 229910000831 Steel Inorganic materials 0.000 description 9
- 239000007789 gas Substances 0.000 description 9
- 239000002184 metal Substances 0.000 description 9
- 229910052751 metal Inorganic materials 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- 230000000694 effects Effects 0.000 description 8
- 230000002829 reductive effect Effects 0.000 description 8
- 230000008859 change Effects 0.000 description 7
- 238000009863 impact test Methods 0.000 description 7
- 239000000523 sample Substances 0.000 description 7
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 238000011282 treatment Methods 0.000 description 5
- 230000013011 mating Effects 0.000 description 4
- 230000000717 retained effect Effects 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000032683 aging Effects 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 238000005219 brazing Methods 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000012159 carrier gas Substances 0.000 description 3
- 238000005336 cracking Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 238000005121 nitriding Methods 0.000 description 3
- 238000005498 polishing Methods 0.000 description 3
- 230000009466 transformation Effects 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000011109 contamination Methods 0.000 description 2
- 238000009661 fatigue test Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000007656 fracture toughness test Methods 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 239000010687 lubricating oil Substances 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- MPCRDALPQLDDFX-UHFFFAOYSA-L Magnesium perchlorate Chemical compound [Mg+2].[O-]Cl(=O)(=O)=O.[O-]Cl(=O)(=O)=O MPCRDALPQLDDFX-UHFFFAOYSA-L 0.000 description 1
- 241001422033 Thestylus Species 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 238000005255 carburizing Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000032798 delamination Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 229910001873 dinitrogen Inorganic materials 0.000 description 1
- 238000004453 electron probe microanalysis Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000011089 mechanical engineering Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000013001 point bending Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/34—Rollers; Needles
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/32—Balls
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/66—Special parts or details in view of lubrication
- F16C33/6637—Special parts or details in view of lubrication with liquid lubricant
- F16C33/664—Retaining the liquid in or near the bearing
- F16C33/6651—Retaining the liquid in or near the bearing in recesses or cavities provided in retainers, races or rolling elements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C2240/00—Specified values or numerical ranges of parameters; Relations between them
- F16C2240/40—Linear dimensions, e.g. length, radius, thickness, gap
- F16C2240/54—Surface roughness
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
- F16C33/30—Parts of ball or roller bearings
- F16C33/58—Raceways; Race rings
- F16C33/62—Selection of substances
Definitions
- the present invention relates to a rolling bearing, and can be applied to, for example, a roller bearing used in a shaft support portion of an automobile transmission.
- JP-A-2-168021 and JP-A-6-42536 describe rolling bearings in which minute irregularities are formed on the surface of a rolling element to improve oil film forming ability.
- minute concave recesses are provided on the rolling surface and Z or inner and outer ring raceways, and the surface roughness is set as a parameter.
- the value of the ratio of the axial surface roughness Rqni (L) to the circumferential surface roughness Rqni (C) Rqni (L) ZRqni (C) is 1.0 or less, and the surface roughness
- the parameter Sk is set to ⁇ 1.6 or less, so that the long life is achieved even when the mating surface is rough or good.
- the surface roughness is expressed by the parameter Rqni for a conventional recess with a small concave shape
- the value of the ratio of the surface roughness Rqni (L) in the axial direction to the surface roughness Rqni (C) in the circumferential direction Rqni (L ) ZRqi (C) is 1.0 or less (Rqni ⁇ 0.10)
- the surface roughness parameter Sk is set to 1.6 or less, so that even if the mating surface is rough, Although the finished surface has a long life, the effect may not be fully achieved when the oil film thickness is extremely thin under low viscosity and dilute lubrication.
- the rolling bearing of the present invention at least on the surface of the rolling element, provided indentations having a micro recess-like shape are countless randomly, the average area of the recess 30: in LOO mu m 2 range, and, Ry max is in the range of 0.4 to 1.0.
- At least one of the outer member, the inner member, and the rolling element of the rolling bearing has a nitrogen-enriched layer, and the particle size number of the austenite crystal grains in the nitrogen-enriched layer May be in the range above 10.
- a rolling bearing is a mechanical element that supports a shaft that rotates or swings by a rolling motion of a rolling element (ball or roller).
- the rolling element is freely rollable between the inner ring raceway and the outer ring raceway, but it does not have an inner ring with the outer peripheral surface of the shaft as the direct raceway surface, for example, the inner peripheral surface of a gear.
- the inner member and the outer member are used is not limited to the inner ring and the outer ring, but does not exclude shafts or gears having raceway surfaces.
- At least the surface of the rolling element is intended not to exclude the formation of a micro-concave depression on the raceway surface, and when the rolling element is a roller, not only the rolling surface. The purpose of this is not to exclude the formation of a concave indentation on the end face.
- the value of the ratio between the axial surface roughness Rq ni (L) and the circumferential surface roughness Rqni (C) Rqni (L ) ZRqni (C) may be 1.0 or less.
- Parameter Rqni is the square root of the value obtained by integrating the square of the height deviation up to the roughness center line force over the measurement length interval and averaging it over that interval, also known as the mean square root roughness. (ISO 4287: 1997) o Rqni is obtained by numerical calculation from the recorded cross-sectional curve and roughness curve, and is measured by moving the stylus probe in the width direction and circumferential direction. Determine.
- the nitrogen-enriched layer is a layer with an increased nitrogen content formed on the surface layer of the raceway ring (outer ring or inner ring) or the rolling element, and is formed by a process such as carbonitriding, nitriding, or nitriding. Can be made.
- the nitrogen content in the nitrogen enriched layer is preferably in the range of 0.1% to 0.7%. If the nitrogen content is less than 0.1%, the effect will be reduced, and the rolling life will be reduced, especially under the conditions of foreign matter contamination. If the nitrogen content is more than 0.7%, voids called voids will be formed, or the retained austenite will increase so much that the hardness will not be achieved, resulting in a short life.
- the nitrogen content is the value at the surface layer of 50 m of the raceway surface after grinding, for example measured with EPMA (wavelength dispersive X-ray microanalyzer) Can do.
- austenite grain size As the austenite grain size exceeds 10, the austenite grain size becomes finer, so that the rolling fatigue life can be greatly improved. If the austenite grain size number is 10 or less, the rolling fatigue life is not greatly improved. Usually 11 or higher. Although it is desirable that the austenite grain size is finer, it is usually difficult to obtain a grain size number exceeding 13. Note that the austenite grains of the bearing parts described above do not change either in the surface layer portion having the nitrogen-enriched layer or in the inside thereof. Therefore, the target positions in the above range of the grain size number are the surface layer and the inside.
- An austenite crystal grain is, for example, a crystal grain based on the trace of the austenite crystal grain boundary immediately before quenching after quenching.
- the nitrogen content in the nitrogen-enriched layer may be in the range of 0.1% to 0.7%.
- the nitrogen content can be a value in the surface layer 50 m of the raceway surface after grinding.
- FIG. 1 is a cross-sectional view of a needle roller bearing.
- FIG. 2 is a cross-sectional view of a needle roller bearing used for a life test.
- FIG. 3 is a roughness curve diagram showing a finished surface state of a rolling element in a test bearing.
- FIG. 4 is a roughness curve diagram showing the finished surface condition of rolling elements in a test bearing.
- FIG. 5 is a roughness curve diagram showing the finished surface condition of the rolling elements in the test bearing.
- FIG. 6 is a schematic view of a test apparatus.
- FIG. 7 is a graph showing the life test results.
- FIG. 8 is a cross-sectional view of a roller bearing.
- FIG. 9A is a graph showing the metal contact ratio of Examples.
- FIG. 9B is a graph showing the metal contact ratio of a comparative example.
- FIG. 11 A schematic cross-sectional view showing a rolling bearing in an embodiment of the present invention.
- ⁇ 12] is a diagram for explaining a heat treatment method for a rolling bearing in an embodiment of the present invention.
- ⁇ 13] is a diagram for explaining a modification of the heat treatment method for a rolling bearing in an embodiment of the present invention.
- FIG. 14A is a diagram showing the microstructure of bearing parts according to the present invention, particularly austenite grains.
- FIG. 14B is a view showing a microstructure of a conventional bearing part, particularly austenite grains.
- FIG. 15A shows an austenite grain boundary illustrating FIG. 14A.
- FIG. 15B shows an austenite grain boundary illustrating FIG. 14B.
- FIG. 16 is a view showing a test piece of a static crushing strength test (measurement of fracture stress value).
- [17A] A schematic front view of a rolling fatigue life tester.
- FIG. 17B is a side view of the testing machine of FIG. 17A.
- FIG. 18 is a view showing a test piece of a static fracture toughness test.
- a rolling bearing has an inner ring, an outer ring, and rolling elements as main components. Then, an infinite number of minute concave recesses are randomly formed on at least one of the rolling surfaces and end surfaces of the rolling elements and the raceway surfaces of the inner and outer rings (and the large rib surface for the inner ring of the tapered roller bearing) to form minute amounts. It is roughened. This fine rough surface has an average area of depressions in the range of 30 to: LOO / zm 2 and the Rymax of the surface on which the depressions are provided is in the range of 0.4 to 1.0.
- rough surface Rqni (L) is the ratio of the axial surface roughness Rqni (L) to the circumferential surface roughness Rqni (C) ) / Rqni (C) is 1.0 or less, and the surface roughness parameter Sk value is 1.6 or less in both axial and circumferential directions.
- a force shot or the like that can obtain a desired finished surface by special barrel polishing may be used.
- Measuring device Surface roughness measuring instrument Surfcom 1400A (Tokyo Seimitsu Co., Ltd.)
- the area ratio of the indentation occupying the entire rolling surface is within the range of 5 to 20%, and the average area of the indentation is the equivalent circular diameter 3 ⁇ It is 30 to 100 / ⁇ ⁇ 2 when arranged except for the following.
- Rymax is 0.4 to 1. Outside the range of 0, Ku BoMino area ratio exceeds 20%, the average area exceeds 100 m 2, contact effective length reduced a little, the effect of long-life decreased Tend to.
- the surface of the roller is enlarged and its image power is also commercially available. Can be quantitatively measured by an image system. Furthermore, if the surface texture inspection method and the surface texture inspection apparatus disclosed in JP-A-2001-183124 are used, stable and accurate measurement can be performed. The white portion of the image is analyzed as a flat surface portion, and the minute depression is analyzed as a black portion. The measurement conditions are as follows. In addition, when measuring the indentation area and average area for components such as rolling elements of rolling bearings and rail surfaces, it is possible to rely on a single measured value as a representative value.
- Area ratio Percentage of pixels (black) that are smaller than the binary threshold [(brightness + darkness) Z2] in the viewing field range
- Fig. 1 shows a first example of a rolling bearing.
- the rolling bearing 1 is a needle roller bearing in which a needle roller 2 is incorporated in an outer ring 3 as a rolling element. It comes to support.
- the following describes the results of a life test conducted by manufacturing multiple types of needle roller bearings with different surface finishes on the needle roller surface.
- This is a bearing with cage 5 using needle rollers.
- Three types of needle rollers with different surface roughness finishes were manufactured as test bearings.
- bearing A comparative example
- bearing B comparative example
- bearing C comparative example
- Figures 3 to 5 show the surface finish of the needle rollers of each test bearing.
- Fig. 3 shows the surface roughness of bearing A
- Fig. 4 shows the surface roughness of bearing B
- Fig. 5 shows the surface roughness of bearing C.
- Table 1 shows a list of characteristic value parameters for the surface finish of each test bearing.
- the parameter Sk refers to the degree of distortion of the roughness curve (skewness) (ISO 4287: 1997), which is a statistic that indicates the asymmetry of the uneven distribution, and is symmetric like a Gaussian distribution.
- the Sk value is close to 0, and it is negative when the concave and convex portions are deleted, and is positive when the reverse is the case. It will be.
- the Sk value can be controlled by selecting the barrel polishing machine's rotation speed, processing time, workpiece input amount, chip type and size, etc. For example, by setting the Sk value to 1.6 or less in both the width direction and the circumferential direction, a dent with a minute concave shape becomes an oil sump, and even if compressed, the oil film has less oil leakage in the sliding direction and at a right angle. Excellent formation, oil film formation is good, and has the effect of minimizing surface damage.
- Rqni LZC
- the bearing C is 1.0 or less
- the bearing A is a value around 1.0.
- the test apparatus used is a radial load tester 11 as schematically shown in FIG. 6, in which the test bearings 1 are mounted on both sides of the rotary shaft 12, and the test is performed by applying rotation and load.
- the finish of the inner race (mating shaft) used in the test is a polished finish of RaO. 10 to 0.16 / z m.
- the water race (outer ring) is also common.
- the test conditions are as follows.
- the vertical axis in the figure represents the L10 life (h).
- bearing A was 78h and bearing B was 82h, while bearing C was 121h.
- FIG. 8 shows a tapered roller bearing as a second example of the rolling bearing.
- Tapered roller shaft The bearing is a radial bearing using a roller 16 as a rolling element, and a plurality of tapered rollers 16 are interposed between a raceway of the outer ring 13 and a raceway of the inner ring 14 so as to roll freely.
- the rolling surface 17 of the tapered roller 16 is in rolling contact with the raceway of the outer ring 13 and the inner ring 14, and the large end surface 18 of the tapered roller 16 is in sliding contact with the inner surface of the large collar 15 of the inner ring 14. Therefore, in the case of the tapered roller 16, an infinite number of minute concave concaves may be formed on the large end surface 18 in addition to the rolling surface 17.
- an infinite number of minute concave concaves may be formed on the inner surface of the large brim 5 in addition to the raceway surface.
- roller bearing C E and the bearings F and G of the example are formed with an innumerable number of minute concave recesses by barrel polishing special processing.
- roller bearing C G is 1.0 or less
- roller bearings 8 and B are values before and after 1.0.
- a peeling test was conducted using a two-cylinder testing machine shown in Fig. 10, and the metal contact rate was evaluated.
- the drive side cylinder 22 (D cylinder: Driver) and the driven side cylinder 24 (F cylinder: Follow) er) is attached to one end of each rotating shaft, and the two rotating shafts 26 and 28 can be driven by separate motors via pulleys 30 and 32, respectively.
- the shaft 26 on the D cylinder 22 side was driven by a motor, and the F cylinder 24 was free-rolled to follow the D cylinder 22.
- two types of surface treatments were prepared: a comparative example and an example. Details of test conditions are as shown in Table 3.
- FIGS. 9A and 9B Comparison data of metal contact ratio is shown in FIGS. 9A and 9B.
- the horizontal axis represents the elapsed time
- the vertical axis represents the metal contact rate
- Fig. 9A shows the metal contact rate of the roller rolling surface of the bearing of the example
- Fig. 9B shows the roller rolling surface of the comparative example bearing.
- the metal contact ratio of each is shown.
- FIG. 11 shows a cross section of a deep groove ball bearing as another example of a rolling bearing.
- This rolling bearing is composed of an outer ring 34, an inner ring 36, a plurality of rolling elements 38 that are rotatably interposed between the raceway of the outer ring 34 and the raceway of the inner ring 36, and a cage 40. It holds as.
- the rolling elements 38 are balls here, and are held by the retainer 40 at predetermined intervals in the circumferential direction.
- At least one bearing component of the outer ring 34, the inner ring 36, and the rolling element 38 constituting the rolling bearing has a nitrogen-enriched layer.
- a heat treatment including a carbonitriding process will be described as a specific example of the process for forming the nitrogen-enriched layer.
- FIG. 12 is a diagram for explaining a heat treatment method for a rolling bearing according to the embodiment of the present invention
- FIG. 13 is a diagram for explaining a modification thereof.
- Fig. 12 is a heat treatment pattern showing the method of primary quenching and secondary quenching
- Fig. 13 shows the material A during quenching.
- treatment ⁇ diffuses carbon and nitrogen into the steel substrate.
- process T in the figure, reheat to a temperature above the A transformation point temperature and lower than that of process T.
- the rolling bearing of the present invention produced by the heat treatment pattern shown in FIG. 12 or FIG. 13 has a microstructure in which the grain size of austenite crystal grains is less than half of the conventional one. Bearing parts subjected to the above heat treatment have a long life against rolling fatigue, can improve the cracking strength, and can also reduce the rate of dimensional change over time. Since a heat treatment step for lowering the secondary quenching temperature is performed to refine the crystal grains, the amount of retained austenite is reduced on the surface layer and inside, and as a result, excellent crack strength and aging resistance can be obtained.
- FIGS. 14A and 14B are diagrams showing the microstructure of bearing parts, particularly austenite grains.
- FIG. 14A shows a bearing part of the present invention example
- FIG. 14B shows a conventional bearing part.
- Snow FIG. 14A shows the austenite grain size of the bearing ring of the rolling bearing according to the embodiment of the present invention to which the heat treatment pattern shown in FIG. 12 is applied.
- FIG. 14B shows the austenite grain size of the bearing steel obtained by the conventional heat treatment method.
- FIGS. 15A and 15B show the austenite grain sizes illustrated in FIGS. 14A and 14B. From the structure showing the austenite crystal grain size, the conventional austenite grain size ⁇ 3 standard grain size number is No. 10, and according to the heat treatment method shown in FIG. 12 or FIG. 13, No. 12 fine grains can be obtained. Further, the average particle diameter in FIG. 14A was measured by the intercept method, and was found to be 5.6 / m.
- Samples A to D (Examples of the present invention): carbonitriding 850 ° C, holding time 150 minutes.
- the atmosphere was a mixed gas of RX gas and ammonia gas.
- the primary quenching is performed from the carbonitriding temperature of 850 ° C! The temperature is lower than the carbonitriding temperature at,,, and, and heated to 780 ° C to 830 ° C for secondary treatment. Quenching was performed. However, Sample A with a secondary quenching temperature of 780 ° C was also excluded from the test due to insufficient quenching.
- Samples E and F (comparative examples): The carbonitriding process is performed with the same history as the inventive examples A to D, and the secondary quenching temperature is 850 ° C to 870 which is 850 ° C or higher. Performed at ° C.
- Conventional carbonitrided product Carbonitriding 850 ° C, holding time 150 minutes. The atmosphere was a mixed gas of RX gas and ammonia gas. Quenching was performed as it was from the carbonitriding temperature, and secondary quenching was not performed.
- Normal hardened product without any carbonitriding treatment, it was quenched by heating to 850 ° C. The secondary quenching was powerful.
- the amount of hydrogen was analyzed for the amount of non-diffusible hydrogen in the steel using a DH-103 hydrogen analyzer manufactured by LECO. The amount of diffusible hydrogen is not measured.
- the specifications of this LECO DH-103 hydrogen analyzer are shown below.
- Sample weight size 1 Omg to 35 mg (Maximum: Diameter 12mm X Length 1 OOmm)
- Carrier gas nitrogen gas
- gas dosing gas hydrogen gas
- both gases have a purity of 99.99% or more and a pressure of 40 psi (2.8 kgfZcm 2 ).
- the outline of the measurement procedure is as follows. Sample collected by a dedicated sampler Insert the entire flask into the hydrogen analyzer. The internal diffusible hydrogen is led to the thermal conductivity detector by the nitrogen carrier gas. This diffusible hydrogen is not measured in this example. Next, the sample is taken out from the sampler, heated in a resistance heating furnace, and non-diffusible hydrogen is led to the thermal conductivity detector by nitrogen carrier gas. The amount of non-diffusible hydrogen can be determined by measuring the thermal conductivity with a thermal conductivity detector.
- the crystal grain size was measured based on the JIS G 0551 steel austenite grain size test method.
- the Charpy impact test was performed based on the Charpy impact test method for metal materials of JIS Z 2242.
- As the test piece a U-notch test piece (JIS No. 3 test piece) shown in JIS Z 2202 was used.
- FIG. 16 is a diagram showing a test piece for a static crushing strength test (measurement of fracture stress value). Measure the load until it breaks by applying the load in the P direction in the figure. After that, the obtained fracture load is converted into a stress value by the bending beam stress calculation formula shown below.
- the test piece is not limited to the test piece shown in FIG. 16, and a test piece having another shape may be used.
- the fiber stress on the convex surface of the test piece in FIG. 16 is ⁇ , and the fiber stress on the concave surface is ⁇ .
- Outer radius, e represents inner radius.
- ⁇ is the section modulus of the curved beam.
- FIGS. 17A and 17B are schematic views of a rolling fatigue life tester.
- FIG. 17A is a front view
- FIG. 17B is a side view.
- the rolling fatigue life specimen 48 is driven by the drive roll 42. And rotating in contact with the ball 46.
- the ball 46 is a 3Z4 inch ball, which is guided by the inner roll 44 and rolls while applying high surface pressure to the rolling fatigue life test piece 48.
- the austenite grains are remarkably refined to a grain size number of 11 to 12. ! / Speak.
- the austenite grains of Samples E and F, as well as the conventional carbonitrided and conventional quenched products have a grain size number of 10, and are coarser than those of Samples B to D of the inventive examples.
- the Charpy impact value of the conventional carbonitrided product is 5.33 j / cm 2
- the Charpy impact values of Samples B to D of the present invention are 6.30 to 6.65 jZcm. A high value of 2 is obtained. Of these, the lower the secondary quenching temperature, the higher the Charpy impact value.
- Charpy impact value of the normal quenched sample as high as 6. 70jZcm 2.
- the fracture stress value corresponds to the crack resistance strength.
- the conventional carbonitrided product has a fracture stress value of 2330 MPa.
- the fracture stress values of Samples B to D are improved to 2650 to 2840 MPa.
- Fracture stress value of normal hardened product is It is estimated that the improved cracking resistance strength of Samples B to D, along with the refinement of austenite crystal grains, is significant due to the reduction of the hydrogen content!
- the normal fatigue-hardened product has the lowest rolling fatigue life L, reflecting that it does not have a carbonitriding layer in the surface layer. Compared to this, the rolling fatigue life of conventional carbonitrided products is 3
- Samples B to D of the examples of the present invention have a reduced hydrogen content, austenite grain size refined to 11th or more, Charpy impact value, crack resistance strength and rolling fatigue life. Will be improved.
- Example II A series of tests were conducted on the following X, Y and Z materials.
- JIS standard SUJ2 material (1.0 wt% C—0.25 wt% Si—0.4 wt% Mn—l. 5 wt% Cr) is used for the heat treatment material. did.
- the manufacturing history of materials X to Z is as follows.
- Y material (comparative example): quenching after carbonitriding (conventional carbonitriding). Carburizing Nitriding temperature 845 ° C, holding time 150 minutes. The atmosphere of carbonitriding was RX gas + ammonia gas.
- Example of the present invention Bearing steel subjected to the heat treatment pattern of FIG. Carbonitriding temperature 845 ° C, holding time 150 minutes. The atmosphere of carbonitriding was RX gas + ammonia gas. The final quenching temperature was 800 ° C.
- test conditions and test equipment for rolling fatigue life are as shown in Table 5 and FIGS. 17A and 17B as described above.
- Table 6 shows the results of this rolling fatigue life test.
- the Y material of the comparative example is the same as the L material of the X material, which was also subjected to normal quenching in the same comparative example.
- the service life (the life of one of the 10 specimens that breaks) is 3.1 times longer, and the effect of extending the life by carbonitriding is recognized.
- the Z material of the present invention shows a long life of 1.74 times that of the B material and 5.4 times that of the X material. The main reason for this improvement is thought to be the refinement of the microstructure.
- the Charpy impact value of the carbonitrided ⁇ material is X
- FIG. 18 is a view showing a test piece of the static fracture toughness test. After introducing a pre-crack about 1 mm into the notch of this test piece, a static load by three-point bending was applied to determine the fracture load P. The following formula was used to calculate the fracture toughness value ( KiC value). The test results are shown in Table 8 .
- Klc (PLv r aXBW 2 ) ⁇ 5.8 ⁇ 9. 2 (a / W) +43.6 (a / W) 2
- the brazing material of the present invention example can obtain a value about 1.2 times that of the comparative example. It was.
- the static crushing strength test piece had the shape shown in FIG.
- a static crushing strength test was performed with a load applied in the p direction.
- Table 9 shows the test results.
- the carbonitriding material subjected to carbonitriding is slightly lower than the ordinary quenching X material.
- the brazing material of the example of the present invention has an improved static crushing strength than that of the brazing material, and a level comparable to that of the X material is obtained.
- Table 10 shows the measurement results of the dimensional change over time at a holding temperature of 130 ° C and a holding time of 500 hours, together with the surface hardness and the amount of retained austenite (50 m depth).
- the Z material of the example of the present invention has 2 minutes It turns out that it is suppressed to 1 or less.
- Table 11 shows the results of tests conducted on the relationship between the nitrogen content and the rolling life under the contamination condition.
- the tapered roller bearing shown in FIG. 8 is used, and in Examples 1 to 5, all of the outer ring 13, the inner ring 14, the tapered ring, and the roller 16 are manufactured by the heat treatment pattern shown in FIG. .
- countless indentations shown in Tables 1 and 2 are formed on the surface of the tapered rollers innumerably.
- Comparative Example 1 is a standard hardened product
- Comparative Example 2 is a standard carbonitrided product.
- Comparative Example 3 is a case where only the amount of nitrogen is excessive although the same treatment as in the embodiment of the present invention is performed.
- the test conditions are as follows.
- Test bearing Tapered, roller bearing 30206 (both inner and outer rings and rollers are made of JIS high carbon chrome bearing steel class 2 (SUJ2))
Abstract
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/628,671 US20080193069A1 (en) | 2004-06-25 | 2005-05-24 | Rolling Bearing |
EP05743781A EP1770292A4 (en) | 2004-06-25 | 2005-05-24 | ROLLER BEARING |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2004-188690 | 2004-06-25 | ||
JP2004188690A JP2006009964A (ja) | 2004-06-25 | 2004-06-25 | 転がり軸受 |
JP2004198617A JP2006022819A (ja) | 2004-07-05 | 2004-07-05 | 転がり軸受 |
JP2004-198617 | 2004-07-05 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2006001149A1 true WO2006001149A1 (ja) | 2006-01-05 |
Family
ID=35781677
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2005/009449 WO2006001149A1 (ja) | 2004-06-25 | 2005-05-24 | 転がり軸受 |
Country Status (3)
Country | Link |
---|---|
US (1) | US20080193069A1 (ja) |
EP (1) | EP1770292A4 (ja) |
WO (1) | WO2006001149A1 (ja) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE602005027842D1 (de) * | 2004-06-25 | 2011-06-16 | Ntn Toyo Bearing Co Ltd | Walzlager |
JP5920221B2 (ja) | 2010-11-12 | 2016-05-18 | 日本精工株式会社 | 作動装置の製造方法 |
US10781857B2 (en) | 2016-11-08 | 2020-09-22 | Carrier Corporation | Hybrid bearings |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0130008B2 (ja) * | 1984-07-14 | 1989-06-15 | Ntn Toyo Bearing Co Ltd | |
JPH03117725A (ja) * | 1989-09-28 | 1991-05-20 | Ntn Corp | 転がり軸受 |
JPH04266410A (ja) * | 1991-02-21 | 1992-09-22 | Ntn Corp | 圧延用ローラの軸受 |
JPH04282018A (ja) * | 1991-02-21 | 1992-10-07 | Ntn Corp | オートマチックトランスミッション用軸受 |
JPH0642536A (ja) * | 1988-05-30 | 1994-02-15 | Ntn Corp | 転動ローラ |
JPH06341441A (ja) * | 1993-05-31 | 1994-12-13 | Nippon Seiko Kk | 転がり軸受 |
JPH08311603A (ja) * | 1994-09-29 | 1996-11-26 | Nippon Seiko Kk | 転がり軸受 |
JP2000205284A (ja) * | 1999-01-13 | 2000-07-25 | Koyo Seiko Co Ltd | 転がり摺動部品 |
JP2003226919A (ja) * | 2001-11-29 | 2003-08-15 | Ntn Corp | 軸受部品および転がり軸受 |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2219359B (en) * | 1988-05-30 | 1992-11-04 | Ntn Toyo Bearing Co Ltd | Roller elements for machine parts such as roller bearings. |
JP2548811B2 (ja) * | 1989-11-30 | 1996-10-30 | エヌティエヌ株式会社 | 機械部品 |
US7438477B2 (en) * | 2001-11-29 | 2008-10-21 | Ntn Corporation | Bearing part, heat treatment method thereof, and rolling bearing |
ES2255651T3 (es) * | 2002-10-17 | 2006-07-01 | Ntn Corporation | Rodamiento de rodillos de tipo integral y seguidores de levas de rodillos para motor. |
-
2005
- 2005-05-24 US US11/628,671 patent/US20080193069A1/en not_active Abandoned
- 2005-05-24 EP EP05743781A patent/EP1770292A4/en not_active Withdrawn
- 2005-05-24 WO PCT/JP2005/009449 patent/WO2006001149A1/ja active Application Filing
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0130008B2 (ja) * | 1984-07-14 | 1989-06-15 | Ntn Toyo Bearing Co Ltd | |
JPH0642536A (ja) * | 1988-05-30 | 1994-02-15 | Ntn Corp | 転動ローラ |
JPH03117725A (ja) * | 1989-09-28 | 1991-05-20 | Ntn Corp | 転がり軸受 |
JPH04266410A (ja) * | 1991-02-21 | 1992-09-22 | Ntn Corp | 圧延用ローラの軸受 |
JPH04282018A (ja) * | 1991-02-21 | 1992-10-07 | Ntn Corp | オートマチックトランスミッション用軸受 |
JPH06341441A (ja) * | 1993-05-31 | 1994-12-13 | Nippon Seiko Kk | 転がり軸受 |
JPH08311603A (ja) * | 1994-09-29 | 1996-11-26 | Nippon Seiko Kk | 転がり軸受 |
JP2000205284A (ja) * | 1999-01-13 | 2000-07-25 | Koyo Seiko Co Ltd | 転がり摺動部品 |
JP2003226919A (ja) * | 2001-11-29 | 2003-08-15 | Ntn Corp | 軸受部品および転がり軸受 |
Non-Patent Citations (1)
Title |
---|
JAPANESE STANDARDS ASSOCIATION: "JIS B 0601:2001", 31 January 2002, JIS HANDBOOK KIKAI YOS, pages: 177 - 190, XP002997798 * |
Also Published As
Publication number | Publication date |
---|---|
US20080193069A1 (en) | 2008-08-14 |
EP1770292A1 (en) | 2007-04-04 |
EP1770292A4 (en) | 2007-08-01 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2006001124A1 (ja) | 転がり軸受 | |
JP2007046717A (ja) | ジョイント用爪付き転動軸 | |
WO2013084864A1 (ja) | 機械部品、転がり軸受、円錐ころ軸受および機械部品の製造方法 | |
CN112119169A (zh) | 轴承部件 | |
WO2014196428A1 (ja) | 軸受部品および転がり軸受 | |
JP5163183B2 (ja) | 転がり軸受 | |
JP2008151236A (ja) | 転がり軸受 | |
JPWO2008050378A1 (ja) | 歯車および歯車駆動装置 | |
WO2006001149A1 (ja) | 転がり軸受 | |
JP2007092963A (ja) | 油圧ポンプ用転がり軸受 | |
JP4857746B2 (ja) | 転がり支持装置 | |
JP2007186760A (ja) | 転がり軸受用軌道輪の製造方法及び転がり軸受 | |
JP2005114144A (ja) | 転がり軸受 | |
WO2006001144A1 (ja) | 転がり軸受 | |
JP2003227518A (ja) | 軸受部品および転がり軸受 | |
WO2018159840A1 (ja) | 軸受部品及び転がり軸受、ならびに軸受部品の製造方法 | |
JP2006112558A (ja) | 円すいころ軸受 | |
JP2006316821A (ja) | プラネタリギヤ機構用転がり軸受 | |
JP2005114148A (ja) | 転がり軸受 | |
JP4362394B2 (ja) | コンプレッサ用軸受 | |
JP4757458B2 (ja) | 転がり軸受 | |
JP2006022820A (ja) | 転がり軸受 | |
CN1973144A (zh) | 滚动轴承 | |
JP2006112557A (ja) | 円すいころ軸受 | |
JPH1068419A (ja) | 転がり軸受 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2005743781 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 200580021198.0 Country of ref document: CN |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
WWW | Wipo information: withdrawn in national office |
Country of ref document: DE |
|
WWP | Wipo information: published in national office |
Ref document number: 2005743781 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 11628671 Country of ref document: US |