CN105807025B - A kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type - Google Patents
A kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type Download PDFInfo
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- CN105807025B CN105807025B CN201610328786.9A CN201610328786A CN105807025B CN 105807025 B CN105807025 B CN 105807025B CN 201610328786 A CN201610328786 A CN 201610328786A CN 105807025 B CN105807025 B CN 105807025B
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 30
- 239000010959 steel Substances 0.000 title claims abstract description 30
- 229910052804 chromium Inorganic materials 0.000 title claims abstract description 26
- 239000011651 chromium Substances 0.000 title claims abstract description 26
- 230000008520 organization Effects 0.000 claims abstract description 21
- 238000010438 heat treatment Methods 0.000 claims abstract description 18
- 229910001566 austenite Inorganic materials 0.000 claims abstract description 17
- 229910001563 bainite Inorganic materials 0.000 claims abstract description 16
- 229910000734 martensite Inorganic materials 0.000 claims abstract description 15
- 238000012360 testing method Methods 0.000 claims abstract description 14
- 238000004458 analytical method Methods 0.000 claims abstract description 13
- 238000001514 detection method Methods 0.000 claims abstract description 12
- 238000005259 measurement Methods 0.000 claims abstract description 10
- 238000010219 correlation analysis Methods 0.000 claims abstract description 4
- 238000005096 rolling process Methods 0.000 claims description 14
- 238000005266 casting Methods 0.000 claims description 9
- 210000001519 tissue Anatomy 0.000 claims description 9
- 210000002219 extraembryonic membrane Anatomy 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 6
- 230000000717 retained effect Effects 0.000 claims description 6
- 229910001651 emery Inorganic materials 0.000 claims description 5
- 230000008859 change Effects 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- 238000005520 cutting process Methods 0.000 claims description 3
- 238000007688 edging Methods 0.000 claims description 3
- 238000005530 etching Methods 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 claims description 3
- 238000013021 overheating Methods 0.000 claims description 2
- 230000003628 erosive effect Effects 0.000 claims 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims 1
- 239000010931 gold Substances 0.000 claims 1
- 229910052737 gold Inorganic materials 0.000 claims 1
- 238000012544 monitoring process Methods 0.000 abstract description 4
- 238000005516 engineering process Methods 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 4
- 238000011156 evaluation Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 238000005279 austempering Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000004069 differentiation Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000010791 quenching Methods 0.000 description 2
- 230000000171 quenching effect Effects 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical group [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 238000002224 dissection Methods 0.000 description 1
- 238000009940 knitting Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000007669 thermal treatment Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/20—Metals
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/40—Investigating hardness or rebound hardness
Abstract
Comprise the following steps the invention discloses a kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type：a:Determine whether steel grade belongs to high-carbon-chromium bearing steel using correlation analysis instrument；b:Lasso hardness is examined using Rockwell apparatus；c:Metallographic structure preliminary observation：When metallographic structure occurs organizing >=4 grades for M, or when may be organized for B, it is thus necessary to determine that whether belong to martensite or bainite：c1：X-ray stress analysis instrument prepares sample c2：X-ray stress analysis X instrument, accurate measurement bearing parts residual austenite content and halfwidth numerical value.c2.1：Using X-ray stress detection, the remained austenite content of test sample；c2.2：Test halfwidth parameter d:The organization type of part is further confirmed that using the testing result of Rockwell apparatus.This method, which can be realized, to be judged its bearing parts heat-treated sturcture type, and quality monitoring to bearing heat-treatment part product and quick, accurate must be evaluated.
Description
Technical field
The application is related to high-carbon chromium bearing steel bearing part heat treatment metallographic structure type and differentiates the technical field judged,
More particularly to a kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type, it is mainly a kind of differentiation high-carbon-chromium bearing steel horse
Family name's body tissue and the method for quick identification of lower bainite metallographic structure.
Background technology
It is well known that high-carbon-chromium bearing steel is to manufacture one of common used material of bearing parts, its organization type is divided to two major classes：
Metallographic structure of the metallographic structure either based on martensite based on bainite.Different organization types is used different
Operating mode, its quality for being heat-treated metallographic structure affects the life-span of its product, and therefore, bearing industry has one to its metallographic structure
Fixed evaluation rule.Its grade height be according to《JB1255-2014 high-carbon-chromium bearing steel bearings partses heat treatment technics
Condition》Observation is evaluated under 500 times or 1000 times under the microscope.But this metallographic compares evaluation method, by certain bar
The limitation of part.When carrying out organization type judgement and level evaluation using light microscope, only its actual heat is clearly being known
After handling process, it can just make accurate organization type and judge and level evaluation.And in actual production process, bearing mnanufacture factory
There is the product of some outer committee's heat treatment process in family, due in whole heat treatment process can not tracing and monitoring, then by shadow
Ring the differentiation and the judgement of rank of the heat treatment metallographic structure type to bearing parts.In addition in the external bearing finished products part of research
During dissection and analysis, the problem of being also faced with same：Bearing parts after high-carbon-chromium bearing steel heat treatment only passes through micro- sem observation
Judge, it is impossible to differentiate and determine that the tissue is the metallographic structure based on martensite or based on bainite, especially work as high-carbon
When there is acicular constituent form in tissue after chromium bearing steel heat treatment.Using tissues observed under metallographic microscope, there is needle-like group
When being possible to be determined as martensite >=4 grade or bainite structure when knitting, therefore, judge that it organizes shape only with Metallographic Analysis method
State often has certain limitation, and easily determines error.In order to realize the quality monitoring to bearing heat-treatment part product
And quick, accurate must give is evaluated, a kind of new method geared to actual circumstances should be found and carry out organization type judgement.
Tested and analyzed, found when metallographic structure is not with by the conventional project to domestic and international high-carbon chromium bearing steel bearing part
When same state occurs, its residual austenite content, halfwidth data, case hardness numerical value are respectively provided with certain regularity.Profit
This rule is used, it is found that the discriminating of metallographic structure metallographic structure still with bainite based on of a set of discriminating based on martensite is sentenced
Determine method, and Technology for Heating Processing type can be further determined that according to the regularity of its numerical value.
Goal of the invention
It is an object of the invention to provide a kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type.When bearing parts heat
On the premise of handling process is unknowable, it is impossible to accurate to judge high-carbon chromium bearing steel bearing part thermal treatment quality metallographic structure type
The problem of when there is provided a kind of comprehensive detection criterion, its bearing parts heat-treated sturcture type is judged so as to realize,
And quality monitoring to bearing heat-treatment part product and quick, accurate must give are evaluated.
In order to realize the utility model purpose, the present invention is adopted the following technical scheme that：
A kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type of the present invention comprises the following steps：
a:Determine whether steel grade belongs to high-carbon-chromium bearing steel using correlation analysis instrument.
b:Lasso hardness is examined using Rockwell apparatus.To unprocessed casting skin lasso after heat treatment, its part of preliminary grinding is answered
End face；Fabricated part end face can be tested directly；Rolling element should check rolling surface hardness, be placed on V-type fetal membrane, work as roller belts
During angle, it should select to carry the fetal membrane consistent with roller angle.
c:Metallographic structure preliminary observation：Wire cutting prepares width for 10mm on inner and outer ring end face, highly for 15mm's
Metallographic small sample, sample is ground along longitudinal section；Rolling surface is directly ground for rolling element；Observed under the conditions of conventional metallographic etching
Picture in metallographic structure at deep etch, with high-carbon-chromium bearing steel bearings partses heat treatment technics condition standard is compared；
When metallographic structure occurs organizing >=4 grades for M, or, it is necessary to be further determined that by analysis below method when may be organized for B
Whether martensite or bainite are belonged to：
c1：X-ray stress analysis instrument prepares sample：Exceed 200mm casting skin lasso for diameter, should be cut along short transverse
It is the block samples of 20mm-40mm to be cut into width, and surface scale should be ground off on emery wheel, and side edging cooling is answered when grinding sample,
So as to avoid temperature too high, causing the change of tissue influences its detection accuracy；To the casting skin lasso less than 200mm, directly beat
After emery wheel, directly test.Sample preparation is not needed for bearing finished products part, is directly tested.
c2：Using Xstress3000X X-ray stress analysis X instrument, the relevant parameter of instrument is adjusted, it is ensured that the reliability of measurement
And measurement accuracy, accurate measurement bearing parts residual austenite content and halfwidth numerical value.
c2.1：Using X-ray stress detection, the remained austenite content of test sample；Work as retained austenite（%）＜
3%, can preliminary judgement its be lower bainite；Retained austenite（%）For 6% ~ 30%, can preliminary judgement its be martensite.
c2.2：Using X-ray stress detection, halfwidth parameter is tested.The size of X-ray halfwidth and metallographic structure
Type also have certain relation, when halfwidth be 5.157 ~ 5.459 when, can further determine that its organization type be lower bayesian
Body, when halfwidth is 5.300-5.900, it is martensite that can further determine that its organization type.
d:Using the testing result of Rockwell apparatus, when hardness is 58-62HRC, the tissue class of part is further confirmed that
Type is lower bainite, and when hardness is 60-64HRC, the organization type for further confirming that part is martensite.
The invention has the advantages that：
This method is to combine observation metallographic structure, by being examined to residual austenite content, halfwidth, case hardness
Survey, and according to these technical indicators, to realize the accurate judgement to its organization type, and then judge its various types of rank.
It is related to the qualitative question of Technology for Heating Processing simultaneously, belongs to quenching plus lonneal stitch technique or full austempering
Technological problemses.
Embodiment
A kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type of the present invention comprises the following steps：
1st, determine that steel grade is no using correlation analysis instrument and belong to high-carbon-chromium bearing steel.
2nd, lasso hardness is examined using Rockwell apparatus, to carrying out unprocessed casting skin lasso after Overheating Treatment, answers preliminary grinding
The end face of its part, fabricated part end face can be tested directly.Rolling element should check rolling surface hardness, be placed on V-type fetal membrane, when
During roller belts angle, it should select to carry the fetal membrane consistent with roller angle.
3rd, metallographic structure preliminary observation：Wire cutting prepares width for 10mm on inner and outer ring end face, highly for 15mm's
Metallographic small sample, sample is ground along longitudinal section；Rolling surface is directly ground for rolling element.(the examination under the conditions of conventional metallographic etching
Sample polishes+4% nitric acid alcohol etch, 500 times or 1000 times of multiplication factors), the metallographic structure at deep etch is observed, with standard
《JB1255 high-carbon-chromium bearing steel bearings partses heat treatment technics conditions》In picture compare.It is M to occur when metallographic structure
During >=4 grades of tissue, or when may be organized for B, it is necessary to by analysis below method further determine whether to belong to martensite or
Person's bainite.
3.1X X-ray stress analysis Xs instrument prepares sample：Exceed 200mm casting skin lasso for diameter, should be cut along short transverse
It is the block samples of 20mm-40mm to be cut into width, and surface scale should be ground off on emery wheel, and side edging cooling is answered when grinding sample,
So as to avoid temperature too high, causing the change of tissue influences its detection accuracy；To the casting skin lasso less than 200mm, directly beat
After emery wheel, directly test.For finished product lasso（Rolling element）Sample preparation is not needed, is directly tested.
3. 2 use Xstress3000X X-ray stress analysis X instrument, adjust instrument relevant parameter, it is ensured that measurement it is reliable
Property and measurement accuracy, accurate measurement bearing parts residual austenite content and halfwidth numerical value.
3.2.1 X-ray stress detection, the remained austenite content of test sample are used；According to contrast retained austenite
Amount number, according to its type of the preliminary judgement of table 1.
3.2.2 X-ray stress detection is used, halfwidth is tested.The size of X-ray value of a half width and metallographic structure
Type also has certain relation.According to the test result of halfwidth, its organization type may further determine that.
4th, using the testing result of Rockwell apparatus, the organization type of part is further confirmed that.
This method is to combine observation metallographic structure, by being carried out to residual austenite content, halfwidth data, case hardness
Detection, and 1 is shown in Table according to these technical indicators, to realize the accurate judgement to its organization type, and then judge its all kinds
Rank.It is related to the qualitative question of Technology for Heating Processing simultaneously, belongs to quenching plus lonneal stitch technique or full bainite
The technological problemses of isothermal hardening.
The metallographic structure Type Synthesis judgment basis of table 1
Two examples detected using the method for resolution high-carbon-chromium bearing steel metallographic structure type of the present invention：
Example one：Lasso after heat, it is desirable to Bainitic hardening technique, by analyzing its organization type, judges that technique performs feelings
Condition.
Example two：Certain factory's finished product rolling element, Technology for Heating Processing is not known, it is desirable to analyze its organization type.
Using past single metallographic method, accuracy rate is relatively low；Using resolution high-carbon-chromium bearing steel metallographic of the present invention
The method of organization type, testing result and judgement conclusion are shown in Table 2.
The metallographic structure Type Synthesis of table 2 judges example
| Example | Hardness（HRC） | Retained austenite | Halfwidth | Organization type | Technology type |
| Example one | 60.0,60.0,60.0 | ＜ 3%, ＜ 3%, ＜ 3% | 5.271,5.320,5.357 | B1 grades of lower bainite | Austempering |
| Example two： | 61.3,61.4,61.1 | 16.3,21.4,19.9 | 5.453,5.441,5.337 | M4 grades of martensite | Marquench adds lonneal |
Claims (2)
1. a kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type, it is characterized in that：It the described method comprises the following steps：
a:Determine whether steel grade belongs to high-carbon-chromium bearing steel using correlation analysis instrument；
b:Utilize the hardness of Rockwell apparatus check bearing part；
c:Metallographic structure preliminary observation：Wire cutting prepares width for 10mm on inner and outer ring end face, highly the metallographic for 15mm
Small sample, sample is ground along longitudinal section；Rolling surface is directly ground for rolling element；Observe deep rotten under the conditions of conventional metallographic etching
Picture in metallographic structure at erosion, with high-carbon-chromium bearing steel bearings partses heat treatment technics condition standard is compared；Work as gold
When phase constitution occurs organizing >=4 grades for M, or, it is necessary to be further determined whether by analysis below method when may be organized for B
Belong to martensite or bainite：
c1：X-ray stress analysis instrument prepares sample：Exceed 200mm casting skin lasso for diameter, should be cut into along short transverse
Width is the block samples of 20mm-40mm, and surface scale should be ground off on emery wheel, and side edging cooling is answered when grinding sample, so that
Avoid temperature too high, causing the change of tissue influences its detection accuracy；To the casting skin lasso less than 200mm, direct sanding wheel
Afterwards, directly test；Sample preparation is not needed for bearing finished products part, is directly tested；
c2：Using Xstress3000X X-ray stress analysis X instrument, the relevant parameter of instrument is adjusted, it is ensured that the reliability of measurement and survey
Accuracy of measurement, accurate measurement bearing parts residual austenite content and halfwidth numerical value；
c2.1：Using X-ray stress detection, the remained austenite content of test sample；Work as retained austenite（%）＜ 3%, can
Preliminary judgement its be lower bainite；Retained austenite（%）For 6% ~ 30%, can preliminary judgement its be martensite；
c2.2：Using X-ray stress detection, halfwidth parameter is tested；The size of X-ray value of a half width and metallographic structure
Type also has certain relation, and when halfwidth is 5.157 ~ 5.459, it is lower bainite that can further determine that its organization type,
When halfwidth is 5.300-5.900, it is martensite that can further determine that its organization type；
d:Using the testing result of Rockwell apparatus, when hardness is 58-62HRC, the organization type for further confirming that part is
Lower bainite, when hardness is 60-64HRC, the organization type for further confirming that part is martensite.
2. a kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type according to claim 1, it is characterized in that：Utilize
During Rockwell apparatus check bearing part hardness, to carrying out unprocessed casting skin lasso after Overheating Treatment, its part of preliminary grinding is answered
End face, fabricated part end face can be tested directly；Rolling element should check rolling surface hardness, be placed on V-type fetal membrane, when roller belts angle
When spending, it should select to carry the fetal membrane consistent with roller angle.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201610328786.9A CN105807025B (en) | 2016-05-18 | 2016-05-18 | A kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type |
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| CN201610328786.9A CN105807025B (en) | 2016-05-18 | 2016-05-18 | A kind of method for differentiating high-carbon-chromium bearing steel metallographic structure type |
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| CN107561107A (en) * | 2017-08-24 | 2018-01-09 | 中国农业大学 | A kind of method of reverse D types knotter material |
| CN114378403B (en) * | 2021-12-13 | 2023-05-12 | 首钢京唐钢铁联合有限责任公司 | Method for rapidly judging longitudinal cutting type of steel grade |
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| EP0541825A4 (en) * | 1991-06-04 | 1995-10-11 | Nippon Steel Corp | Method of estimating material of steel product |
| CN102135506A (en) * | 2010-01-26 | 2011-07-27 | 宝山钢铁股份有限公司 | Method for detecting residual austenite in steel plate on line |
| CN104215489B (en) * | 2014-09-19 | 2017-12-01 | 上海材料研究所 | A kind of high-carbon-chromium bearing steel retained austenite standard specimen preparation method |
| CN104236993B (en) * | 2014-09-19 | 2016-08-24 | 北京科技大学 | A kind of method simultaneously showing bearing steel austenite grain boundary and intracrystalline martensite |
| CN105043909B (en) * | 2015-06-29 | 2018-03-27 | 三环集团有限公司 | A kind of detection method of high carbon chromium long-life bearing part after carbo-nitriding |
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Address after: 471039 No. 96, Jianxi, Luoyang District, Henan, Jianshe Road Patentee after: Luoyang Bearing Group Co.,Ltd. Country or region after: China Address before: 471039 No. 96, Jianxi, Luoyang District, Henan, Jianshe Road Patentee before: LUOYANG LYC BEARING Co.,Ltd. Country or region before: China |