This standard specifies the requirements for the inspection of gear materials and heat treatment quality, and gives the contact and bending fatigue limit values ​​corresponding to the material quality grades (ML, MQ, ME and MX). This standard applies to the inspection of gear materials and heat treatment quality made of steel and cast iron. GB/T 8539-2000 General provisions for the inspection of gear materials and heat treatment quality GB/T8539-2000 standard download decompression password: www.bzxz.net

1CS_21.200
National Standard of the People's Republic of China
GB/T8539-2000
eqyIso6336-5:1996
General specification for quality inspectionof gear materials and their heat treatment2000-07-24Promulgated
2000-12-01Implementation
State Administration of Quality Supervision, Inspection and Quarantine
GB/T 8539—2000
Technical standard is a revision of GB/T8539~-1987General specification for quality inspectionof gear materials and their heat treatment. This standard is equivalent to 1ISO6336-5:1996, which is the main technical content of calculation method for load capacity of involute spur gears and helical gears Part 5: Material strength and quality.
From the date of implementation of this standard: replace GB/T8539-1987, Appendix A of this standard is the standard appendix, and Appendix B to Appendix F are the indicative appendices. This standard is proposed by the State Machinery Industry Bureau. This standard is under the jurisdiction of the National Gear Standardization Technical Committee. This standard was drafted by Zhengzhou Machinery Research Institute, and the drafters of the standard revision are Yang Xingyuan, Tu Aixiang, Zhang Guangguo, Zhang Min'an, and Ma Xinqing. This standard was first issued on December 30, 1987. GB/T8539-2000
ISO Foreword
TSO (International Organization for Standardization) is a federation of international standards organizations (ISO member countries) in the world. International standards are usually drafted by the technical committees of ISO (). Member countries interested in the work items of a technical committee have the right to participate in the work of the technical committee. International organizations, governments and non-governmental organizations that have cooperative relations with ISO can participate in its work. ISO) works closely with the International Electrotechnical Commission (IEC) in the promotion of electrical standards.
Draft international standards adopted by the technical committee are circulated to the member countries for voting. For official publication, more than 75% of the votes of the member countries are required.
International Standard 6336 was prepared by Subcommittee 2 (Calculation of load-bearing capacity of gears) of the Technical Committee IS0/TC60 on Gears. 1S06336 includes the following parts under the general title "Calculation method of load-bearing capacity of involute cylindrical gears and helical gears": Part 1: Overview of basic principles and general influence factors Part 2: Calculation of tooth contact fatigue strength Part 3: Calculation of gear tooth deformation fatigue strength Part 5: Material strength and quality
1 Scope
National Standard of the People's Republic of China
General specirication for quality Inspectionof gear materials and their heat treatment GB/T 8539-2000
eqv ISo 6336-5:1996
Replaces GB/T8539—1987
This standard specifies the gear material and heat treatment quality inspection requirements, and gives the corresponding bending fatigue limit values ​​(Figures 1~14) corresponding to the material quality grades (ML, MQ, MEMX). This standard is applicable to the gear material and heat treatment quality inspection made of steel and cast iron. 2 Referenced standards
The texts contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is revised, the versions shown are valid. All standards will be revised. The parties using this standard should explore the possibility of using the latest versions of the following standards. GB/T 2251988
GB/T 3077
GB/T 3374—1992
GB/T 3480 --1997
GB/T 5617--1985
GR/T 7232—1999
GB/T 7233
G13/T 9450—1988
GB/T 10561
Test method for end-fire resistance of steel (e9vIS0) 642: 979) Alloy structural steel
Basic terminology of gears
Calculation method for load-bearing capacity of involute gears (egvIS06336-16336-31996) Determination of effective hardened layer depth after induction quenching or quenching of steel (egVIS03754; 1976) Terminology of metal heat treatment processes
Ultrasonic flaw detection method and quality rating method for steel castings Determination and verification of effective hardened layer depth after carburizing or quenching of steel parts (c4Y[S02639: 1982) 1989
GB/T 11354—1989
ASTM A388 1091
3 Definitions and symbols
Microscopic evaluation of non-metallic inclusions in steel (eg1SO4963:1979) Nitriding layer depth measurement and metallographic structure inspection of steel piano parts Ultrasonic inspection of large castings and forgings
The definitions of gear terms in this standard refer to GB/T3374. The definitions of heat treatment terms refer to GB/T7232. Symbols and units are as specified in GB/T 3480.
4 Gear material and heat treatment quality inspection requirements 4.1 General principles
The am (contact fatigue limit), Olm (bending fatigue limit) and Pr (or = pimYsr) obtained from different materials and different heat treatment processes are shown in Figures 1 to 14. The material quality grades in the figure are defined as follows: MI represents the strict requirements for the material quality and heat treatment process during gear processing; MQ represents the grade that can be achieved by experienced manufacturers at a normal cost; GB/T 8539-2000 approved by the State Administration of Quality and Technical Supervision on July 24, 2000 and implemented on December 1, 2000; ME represents the grade that can only be achieved with high reliability process control; MX represents the quality requirements for quenched and tempered alloy steel with special considerations for transmission and metallographic structure; 4.2 Gear material and heat treatment inspection requirements The requirements listed in this case have been verified by actual application and are proposed as a recommended document. Gear manufacturers may also use other methods or data based on their own experience or needs. However, the details should be agreed upon by both the gear supplier and the demander, especially for large gears. 4.2.1 Casting, structural steel (Figure 1, Figure 2) Since these steels have no specific chemical composition requirements and the smelting method is not clear, the MQ line is at the lower strength limit (ML, i.e. MQ-MI.), and this type of structural steel is only used for light-loaded gears and secondary gears. When the steel production can meet high-grade requirements or is actually verified, the ME line data can be used.
4.2.2 Blackheart malleable cast iron (Figure 3, Figure 4) This type of material is usually used for small light-loaded gears. When the heat treatment process is properly controlled, the material performance can be improved. From the perspective of reliability, the MQ line is located at the lower limit (ML). If it has been verified in practice, the MF line data can also be used. 4.2.3 Other materials (Figure 5 Figure 14)
The quality and heat treatment inspection requirements of other materials are listed in Tables 1 to 6 Cast iron materials (gray cast iron and ductile iron) Figure 3, Figure 4) Sequence
Chemical composition
Mechanical properties
Body structure
De-stress annealing
Internal gradual five (grain)
Cracks
Not inspected
Not specified
Gray cast iron
100% recommended
Submit the correction certificate
Electric furnace or buckle equipment
Only provide I[B value
Specified but no inspection
Required ap or HB, for the same independent test sample, make a test report. This regulation (for gray alloy ferrite, 5% gold cast iron, ferrite containing blood, no inspection, no determination, ductile iron, only provide HR value, no inspection, 10% inspection, submit casting certificate, electric furnace or equivalent equipment inspection d(o.2dbg,
Representative specimen)
Close to the actual gear tooth part
Quality test HB
Not allowed but repair
Repair is not allowed in the gear tooth part, other parts can only be carried out under the process, and stress annealing should be carried out after welding
[Not specified
Not tested
Not tested
Recommended 50C~80 ℃, not specified
For dead LI Gold cast iron
530-560C
Preserve for appropriate time
Inspect pores, cracks, sand, do not inspect
Eyes, limit defects
Junse you penetrate flaw detection
Do not inspect
Recommend 500~-369Preserve
Preserve for appropriate time
Inspect pores, cracks, sand
Eyes, limit defects
No death Cracks are allowed
100% magnetic powder or color penetrant testing, mass production can be sampled for inspection
Chemical composition
Crystal sphericity
Mechanical properties after heat treatment
Non-destructive testing
Ultrasonic inspection (rough turning state)
Surface crack detection (most irradiated state)
GB/T 8539—2000
Table 2 Non-surface hardened and tempered steel (casting) (Figure 6. Figure 8) ML, MQ
Not tested
Not specified
This specification
100 Follow the original castings·Chu inspection report 5 or finer grain, submit inspection report
Inspection (ac.H, 100 Follow the original castings, submit inspection report. Moment can be recommended by the double force cooperation skin to check the gear tooth root position, for ten people diameter workability, check for defects before cutting teeth. [According to GH/T 7233, qualified standard: Area (25 mm below the tooth root) is 1 Grade, Zone 1 (rest of wheel rim) is Grade 2. No cracks are allowed. 100% magnetic powder or dye penetrant inspection, for large batches of products, inspection can be carried out according to the specified process. The wheel ring is not allowed. Other parts are only allowed to be processed in the same state before heat treatment, and welding is not allowed after tooth cutting. Note: When the quality of the casting reaches the standard of forged steel parts (beating or rolling), the load-bearing capacity of the forged gear paired with the forged steel pinion can also be calculated by the applicable stress value of sensitive steel. However, this situation must be verified by test data or application examples. Table 3 Chemical composition 1) Material purity (according to GB/T10561) Product particle size
Forging ratio*
After heat treatment
Mechanical properties
Microstructure
Non-destructive inspection
Not inspected
Not specified
Not specified
Not specified
Non-surface hardened and tempered steel (forgings or rolled products) Figure 5, Figure 7)MQ
100% original casting, provide inspection reportMX
Steel is deoxidized and refined in the process of making packages, and should be vacuum degassed. Hydrogenation measures should be taken during the casting process. Unless required by the user, it is prohibited to intentionally add calcium, the maximum oxygen content of the section is 25×10', and the purity of zone 1 is inspected according to the G5 10561 method. The inspection area is approximately 20)mm. The following table shows the allowable values ​​of the size of inclusions. Submit the inspection report. A
Mi Jing state
Polymorphous state
Spider state
5 grade or finer grain, submit inspection report
at least 3 times
Polymorphous state
Dispersed state
For ten forgings or diameter 250mm or above: building material + cutting specimens with the same furnace number are inspected n,
(.2),,, and indicators. The specimens are heat treated together with the workpiece, and the whole work
tests the surface hardness HB, which can also be carried out according to the agreement between the supply and demand parties. Submit inspection report
The maximum light temperature is 150℃. The tooth root hardness should meet the drawing requirements
Sand state
Agglomerated state
Dispersed state
Same as ME, the material thermal treatment process is sufficient to ensure the minimum hardness of the tooth root at a certain depth. Control plate and
Spell Appendix A
The microstructure of the wheel training part should be mainly tempered
martensite"
Ultrasonic testing
(Compared to the car state)
Surface cracking effect
Processing state)
! Welding is not specified
GB/T 8539-2000
Table 3 (end)
Test after forging and submit a report. For the large diameter T. parts, it is recommended to check for defects before tooth cutting (according to ASTM A3S8 sensitivity is 3.2mm flat bottom hole for flaw detection, and the flaw detection is scanned from the outer circle to the middle diameter 3G0\. Under the premise of ensuring the same quality, it is allowed to use the detection method jointly designed by the supply and demand parties. ) It is not allowed to have a high rate of fire. The gears should be inspected for surface cracks. The inspection is not allowed to have forging or rate cracks. It can be carried out according to the specified process. The method is negotiated by the supply and demand parties. It is not allowed in the gear teeth, and other parts are only allowed to be roughened before heat treatment. Note: When the quality of special steel parts reaches the quality standard of forged steel parts (forged or rolled), the allowable stress value of forged steel can also be used to calculate the load-bearing capacity of cast steel gears paired with forged steel pinions, but this situation must be verified by test data and application examples. The purity of forged steel and forging ratio standards cannot be used for castings. The inclusion content and shape should be controlled to be spherical, sparse, chain-like inclusions (type 1) or above, but the presence of product boundary sulfide hammer inclusions (type 1) is not allowed. Type). 1) For gears that are used in cold environments below 100°C: Consider the requirements for low-temperature impact performance + consider the fracture morphology transformation and the requirements for non-plastic transition temperature performance: consider using high-composite steel +
consider reducing the cut content to below 0.4%,
consider using heating elements to increase the lubricant temperature. 2) Material purity inspection is only for the tooth cutting area, located at the probe twice the tooth height below the final tooth top diagram. For external gears, the passband of this area of ​​the tooth does not exceed 25% of the radius.
3] Only for forgings made of ingots, for continuous materials, the minimum Forging ratio is 7/1,) On the gear face, the microstructure to the depth of 1.2 tooth height is mainly tempered martensite, with a small amount of precipitated ferrite, upper bainite and fine pearlite allowed, and undissolved blocky martensite is not allowed. For gears with a control face of ≤250mm, the non-martensitic phase transformation products shall not exceed 10%, and for gears with a control face of ≥250mm, it shall not exceed 20%. Table 4, Surface hardening and tempering steel
Chemical composition
Mechanical properties after tempering
Grain spot
Ultrasonic detection
Forging ratio
Preparatory heat treatment ||tt ||Surface wake
Effective hardened layer depth\
(Tested according to GB/T561)
Sheath structure
Non-destructive testing
Surface crack (acid powder or
Color detection2
Flame and induction quenching (forging, rolling or casting) (Figure 10. Figure 12)M1.
Same as Table 3 (quenched and tempered steel 1~-6 items
For the purity requirements of plain carbon steel and certified steel: A
Tempered and tempered structure
48~5GHRC
Dispersed state||tt ||Color state
Dispersion state
Polymerization state
Dispersion preparation
50~-56HRC
The depth of hardened layer refers to the vertical distance from the surface to the hardness equivalent to 80% of the minimum surface hardness specified value. Not specified
Not allowed
Shoot the first batch of workpieces
Spot check, mainly fine needle martensite
Strict inspection, fine needle martensite
Not allowed
All inspection
Gear magnetic particle detection\)
Overheating (especially tooth top)
GB/T 8539—2000
Table 4 (Complete)
Not regulated
Modulus/mm
Strictly prohibited
Maximum defect
Size/mm
Note: This table is applicable to the process of sleeve-type fire-increase rate fire, sleeve-type or gradual induction rate fire. The root of the tooth is hardened and the shape of the hardened layer is shown in Figures 16 and 17. 1) In order to obtain a stable hardening effect, the hardness distribution, hardened layer depth, equipment parameters and process methods should be filed and checked regularly.A representative sample with the same shape and material as 1 is used for the repair process. The preparation and process parameters should be sufficient to ensure good reproducibility of the hardening effect. The hardened layer should cover the entire tooth width and tooth part, including the tooth surface on both sides, the tooth root on both sides and the tooth root corner. 2) In the final processed gear wheel area, no cracks, cracks or wrinkles are allowed in any quality grade of material. No more than 1 within a 25mm tooth width, and no more than 5 within a tooth. It is not allowed to exist below the working tooth center line. For defects exceeding the standard, the gear integrity will not be affected and the user's consent will be obtained to remove the defects. Table 5 Surface hardening nitriding steel and quenched and tempered steel
Chemical composition
After quenching and tempering
Mechanical properties
Grain size Www.bzxZ.net
Overproduction
Building ratio
Preparatory heat treatment
Core requirements
Nitrided (hydrogen-carbon eutectic) layer
Surface hardness
Nitrided steel 2
Thanks Before tempering
Alloy steel
Non-Taiwan alloy"
Surface structure
(H bright layer and
Normal firing layer
Fried magnetic fire bag
After gas, liquid, ion heating (carbon co-bonding) (Figure 13, Figure 14)MQ
Same as Table 3 (16 items of continental steel)
No surface desulfurization quenching or normalizing, where the tempering temperature should be lower than the subsequent nitriding (long ignition) temperature without inspection
aSQ0 N/mm* or HB>26t (Under normal circumstances, the ferrite content should be ≤5%
Effective nitrogen depth refers to the vertical distance from the surface to 400 HV or 40.8 HRC hardness. If the core hardness exceeds 380 HV, then the core hardness + 50 TIV can be used as the limit hardness 630--900 I[Vs:
450 HF
Not specified
23 μm: and mainly =-phase
Same as MQ. If the latent nitrogen is +
, the pitting resistance should be considered
White bright layer: 30 μm, H is mainly e-
Grade 2 (GB/T 11354)
Precision after nitrogen processing "
(Total) Section
G3/T 8539—2000
Table 5 (end)
Special cases, but to prevent the reduction of surface bearing capacity, equipment and process parameters can be controlled. For liquid nitrogen-carbon co-existence, titanium heat-resistant alloy with ventilation or passivation is required to prevent the combustion of the elements during co-existence. Note: 1) For nitrogen or nitrogen-carbon co-existence parts, the hardness of the core after tempering determines its final core hardness. Therefore, under the premise of high quenching and tempering temperature, the hardness value is allowed to be cut (cold working) under the condition of allowing tooth cutting, and the hardness value is as high as possible to increase strength and avoid egg light effect.
2) When measuring the surface hardness, the test load should be directly on the surface, and the test load should be proportional to the depth of the infiltration layer and the hard film. 3) The gear has a low overload resistance and the shape of the inner hand SN state line is gentle, so its impact sensitivity should be considered before design. For the alloy of Ji lead, when the hydrogenation cycle is long, there is a possibility of forming a continuous network of nitrides on the product interface. When using this kind of pot material, special precautions should be listed during heat treatment:
4) Steels containing aluminum nitride or similar are limited to MI and MQ. The limit points of the tooth root stress value mlim of this type of material are: for MI. grade, below 250N/mm; for MQ grade, below 340N/mtm, 5) When the hardness is increased by the self-layer (>10μm), the fatigue strength is reduced due to random reasons. 6) Many nitrided gears have low overload resistance. Therefore, the gears should have a sufficiently high geometric accuracy to limit the proportion of dynamic load in the total tooth load. Table 6
Surface hardening
Chemical composition
Floating properties (according to
GH/T225 inspection
Purity and lubrication
General ratio
Grain size
Rough turning state
Acoustic flaw detection
Surface hardness
Representativeness of workpiece
Surface hardening?
Not inspected||t t||Not inspected
Not specified
Not specified
Not specified
Not specified
Minimum 55
HRC or
(see Appendix C. Conversion of Vickers hardness
conversion of HR
Lumel hardness)
When the modulus is 12mm
, the center line of tooth width
the slope of tooth root area
surface hardness
not specified
after magnetization (carbon-sensitive co-infiltration), forging or rolling) (Figure 9. Figure 11)MQ
100 head tracking original slag, submit inspection reportME
Take samples of the same batch of slag for inspection and submit inspection reportThe steel forest is deoxidized and refined in the package and is degassed by air. Anti-oxidation measures should be taken during porcelain casting. Unless required by the user, intentional addition of calcium is prohibited. The maximum torsion loss is 25×10-°. According to GB/T1056T force method B, the purity of zone 1 is tested, and the inspection area is nearly 200 mm.
The following table shows the allowable values ​​of equivalent inclusion size. A
Dispersed
At least 3 times
Collected
Spider Dispersed
S grade or finer grain, submit for inspection: Aggregated
Push. For large diameter workpieces, the inspection method before cutting is the same as Table 3C Quenched and tempered steel 7. 1 Item)
J8~64HRC or 75.7~81.1HR30N,
precisely meet the requirements of the drawings, the representativeness of the random inspection is consistent with the requirements of the sample c
sporadic
nested
miminate
, products with more than five frying can be randomly inspected
5864HRC into 75.781.1HR30N
When the number of pieces heat treated in the same furnace is ≤5, all of them shall be inspected, otherwise the random inspection
meets the requirements of the drawings, all shall be inspected or representative Hardness of core of test specimen Effective hardening layer depth (according to GR/T9450 test) to surface hardness drop (within the effective hardening layer depth range in China, the difference between the maximum hardness of the secondary layer and the surface hardness. Hardness conversion depends on Appendix GB/T8539-2000 Table 6 (continued) 25HRC The above
estimated measurement position: the middle of the tooth root 30\ upward from the tangent line, the depth is 5 times the hardened layer depth, but not less than 1 times the module: according to the technical requirements, the inspection method provided by both parties can be used for inspection
SSHRC The above
uses representative samples for inspection or similar gears with the same module of the gear block sample. The following items are the above inspections. This indicator is related to the surface contact strength. It is determined under the condition of considering the gear module and the maximum separation force state. The effective hardened layer depth refers to the surface to 550 HV reading 52 IIRC vertical distance outside the hardness extension, when specifying the minimum hardening depth, it should be noted that the optimum values ​​for bending strength and surface bearing capacity are different: In addition, the maximum hardening layer depth cannot be exceeded, otherwise the tooth bending resistance increases
Not specified
For workpieces or representative specimens, the hardness reduction does not exceed 2HRC: When the hardness of the sugar processing state is above 650HV, the hardness reduction is limited to 40HV and the hardness reduction cannot exceed 30 HV
Various microstructure inspections can be carried out on non-representative specimens 1. This inspection is for MQ, and must be inspected for ME (for ML Not required) Surface carbon content
Surface nitrogen content
(carbon and nitrogen co-poisoning)
spots
play austenite
(for representative test samples metallographic examination
non-martensite (GO)
not specified
not checked
semi-continuous carbon
carbide network
(circle 15a)
long carbon content shows +0.2% ~ -0.10, it is recommended that the representative sample is mainly martensite, bainite content is less than 10%
according to the technical conditions. Generally, the nitrogen content does not exceed 0. 3%. Discontinuous carbides are allowed. For representative tests! Spider-like carbides are allowed to be inspected according to the representative samples in 4 and 3. The length of all carbides shall not exceed 0. (12 mm/s) (Fig. 15h)
Can be implemented according to the standards of various industries
Not specified
Can be implemented according to the standards of various industries
Not specified is
25 or less
Deep layer e/mm
0.75e1.50
1.50-e2. 25
2. 25-.6 3. 00
IGO/μm
Test specimen (Fig. 15)
25※The following micro-refining
deep layer e/μm
0. 75<.e≤1. 50
1. 30<.ec2. 25
2. 25ce2.3.00
If out of tolerance, we can cooperate with the user to use controlled shot peening to remedy IGO/am
no detection
surface cracks! Without affecting the integrity of the gear and with the consent of the user, the surface can be removed and the microstructure of the gear core can be inspected by magnetic particle inspection (the position is the same as that of Section 8). Cracks are not allowed. Magnetic particle inspection is used for extraction. Not specified. Not specified. Note: 1) See Table 3 Note 3); GB/T 8539-2000 Table 6 (end) Cracks are not allowed. The powder detection rate should reach 50%
Mold/n2m
Recovery maximum size/mm
According to the relevant industry standards
No cracks are allowed, 1 magnetic particle inspection, batch inspection can be spot checked. The spot check rate is higher than MQ
Respect/mm
.2. 35
Defect quantity size/mm
No central free ferrite
2Due to the difference in size and process, the tooth root hardness may be slightly lower than the tooth surface hardness. The allowable value can be negotiated by the supplier and the supplier: 3) In the gear tooth area after final processing, no cracks, cracks or wrinkles are allowed in any quality level of material. Limit: No more than one in the 25 mm tooth width, and no more than 5 in one side of the tooth surface. The defects below the working gear height are not allowed to exist. The above defects can be removed with the consent of the user without affecting the gear finish. 4.3 Test specimens
The test specimens are made of representative steel and can be forged separately. They go through all heat treatment processes together with the product. The selection of test specimens can control the quality of the heat treatment process in terms of carbon content and microstructure. It can also be selected from the perspective of the representative performance of the workpiece. The performance of the standard test specimen should be close to that of the workpiece in terms of the scratch resistance and paint degree of the carburized layer, and can be inferred based on experience. Regarding the processing of the test specimens, it should be subject to the agreement between the supply and demand parties. Two types of test specimens are recommended here
a) Process test specimens: suitable for any material and shape, it is used to detect the stability of the heat treatment process, its microstructure does not represent the microstructure of the final gear, and the approximate state of the final gear can only be inferred based on actual experience. This inference should be archived for reference. 6) Representative specimen: The cooling rate of the product gear should be considered. The hardness and microstructure of the core of the specimen should be close to the indicators specified in items 8 and 13 of Table 6. The recommended dimensions are: Minimum diameter (mm): 6 × modulus:
Minimum length (mm): 12 × modulus.
In addition, the sample steel should be equivalent to the workpiece in terms of chemical composition and hardenability. 8
1) Normalized wax structural steel
GB/T 8539-2000
Figure 1E Normalized structural steel and cast steel
guur/N
1) Normalized structural sodium
Note r—arinYe
2) Cast steel
2) Normalized structural steel and cast steel F lin and aFE Figure 2
(/N)/n
11 Malleable casting mirror
(ea/K)
Figure 3 Cast iron m
2) Ductile iron
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