BS EN ISO 642-1999 Steel hardenability test by end quenching (Jominy test)《钢端头淬硬性试验(乔米尼(Jominy)试验)》.pdf

1、BRITISH STANDARD BS EN ISO 642:1999 Steel hardenability test by end quenching (Jominy test) The European Standard EN ISO 642:1999 has the status of a British Standard ICS 77.040.99BSENISO642:1999 This British Standard, having been prepared under the directionof the Engineering SectorCommittee, was p

2、ublishedunder the authority ofthe Standards Committee andcomes into effect on 15November 1999 BSI 04-2000 ISBN 0 580 35135 1 National foreword This British Standard is the English language version of ENISO642:1999. It is identical with ISO642:1999. It supersedes BS4437:1987 which is withdrawn. The U

3、K participation in its preparation was entrusted to Technical Committee ISE/72, Methods of Physical and Metallographic Testing, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or p

4、roposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references Attention is drawn to the fact that CEN

5、and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards C

6、atalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for the

7、ir correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN ISO title page, page 2, the ISO title page, pages ii to iv, pages 1 to 18, an ins

8、ide back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSENISO642:1999 BSI 04-2000 i Contents Pag

9、e National foreword Inside front cover Foreword 2 Foreword iii Text of ISO 642 1ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 642 September 1999 ICS 77.040.99 English version Steel Hardenability test by end quenching (Jominy test) (ISO 642:1999) Acier Essai de trempabilit par trem

10、pe en bout (essai Jominy) (ISO 642:1999) Sthle Stirnabschreckversuch (Jominy-Versuch) (ISO 642:1999) This European Standard was approved by CEN on 16 August 1999. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standar

11、d the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, Ge

12、rman). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, CzechRepublic, Denmark, F

13、inland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050

14、 Brussels 1999 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 642:1999 EENISO642:1999 BSI 04-2000 2 Foreword The text of the International Standard ISO642:1999 has been prepared by Technical Committee ISO/TC17 “Steel” in colla

15、boration withTechnical Committee ECISS/TC2 “Steel Physico-chemical and non-destructive testing”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March200

16、0, and conflicting national standards shall be withdrawn at the latest by March2000. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denmark, Finland, Fr

17、ance, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of the International Standard ISO642:1999 was approved by CEN as a European Standard without any modification. NOTENormative refer

18、ences to International Standards are listed in Annex ZA (normative).ENISO642:1999 ii BSI 04-2000 Contents Page Foreword iii 1 Scope 1 2 Normative references 1 3 Principle 1 4 Symbols and designations 1 5 Form of test pieces and their preparation 2 6 Apparatus 3 7 Heating and quenching of test piece

19、6 8 Preparation for, and measurement of, hardness after quenching 7 9 Expression of results 7 10 Test report 8 Annex A (informative) Specification for the hardenability of a product 10 Annex B (informative) Additional information to clause10 13 Annex C (informative) Calculation of the hardenability

20、15 Annex ZA (normative) Normative references to international publications with their relevant European publications 19 Bibliography 16 Figure 1 Sampling by machining of the test piece 3 Figure 2 Dimensions of test piece 4 Figure 3 Diagram of quenching device 5 Figure 4 End of water supply pipe 6 Fi

21、gure 5 Preparation of test piece for measurement of hardness, and position of hardness measurement points 9 Figure 6 Hardness at a distance d of 15 mm 9 Figure A.1 Specification of hardenability by two limiting curves 11 Figure A.2 Specification of hardenability by a given hardness between two dista

22、nce limits 11 Figure A.3 Specification of hardenability by a range of hardness at a given distance 12 Figure B.1 Network of curves giving the ratio / Aas a function of time 13 Figure B.2 Variation of the cooling rates, in degrees Celsius per second, of points on the surface of the Jominy test piece

23、at approximately 700 C as a function of their distance from the quenched end 14ENISO642:1999 BSI 04-2000 iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is

24、normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part

25、in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part3. Draft International Standards adopted by the tec

26、hnical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least75% of the member bodies casting a vote. International Standard ISO 642 was prepared by Technical Committee ISO/TC17 Steel, Subcommittee SC7, Methods of testing (ot

27、her than mechanical tests and chemical analysis). This second edition cancels and replaces the first edition (ISO642:1979) which has been technically revised. Annex A,Annex B, and Annex C of this International Standard are for information only.iv blankENISO642:1999 BSI 04-2000 1 1 Scope This Interna

28、tional Standard specifies a method for determining the hardenability of steel by end quenching (Jominy test) by using a test piece25mm in diameter and100mm long. NOTEBy agreement and for a defined field of application, the test described in this International Standard may be replaced by the calculat

29、ion of the Jominy curve in accordance with an accepted mathematical model (seeAnnex C). In case of dispute, the test shall be carried out. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International St

30、andard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated

31、 below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 6507-1, Metallic materials Vickers hardness test Part 1: Test method. ISO 6508-1, Metallic materials Rockwell ha

32、rdness test Part 1: Test method (scales A, B, C, D, E, F, G, H, K, N, T). ISO 6508-2, Metallic materials Rockwell hardness test) Part 2: Verification and calibration of testing machines (scales A, B, C, D, E, F, G, H, K, N, T). ISO 6508-3, Metallic materials Rockwell hardness test Part 3: Calibratio

33、n of reference blocks (scales A, B, C, D, E, F, G, H, K, N, T). 3 Principle The test consists of: a) heating a cylindrical test piece to a specified temperature in the austenitic range for a specified period of time; b) quenching it by spraying water on one of its ends under specified conditions; c)

34、 measuring the hardness at certain given points, on longitudinal flats made on the test piece, in order to determine the hardenability of the steel by variations of this hardness. 4 Symbols and designations Symbol Designation Value L Total length of test piece (100 0,5) mm D Diameter of test piece m

35、m t Time during which test piece is maintained at heating temperature min t m Maximum time lag between removal of test piece from furnace and start of quenching 5 s T Temperature of cooling water (20 5) C a Internal diameter of vertical water supply pipe (12,5 0,5) mm h Height of water jet without t

36、est piece in position (65 10) mm l Distance from end of water supply pipe to lower end of test piece (12,5 0,5) mm e Depth of flats for measurement of hardness (0,4 to 0,5) mm d Distance, in millimetres, from quenched end to points where hardness is measured Jxx-d Jominy hardenability index at dista

37、nce d, in Rockwell HRC-mm JHVxx-d Jominy hardenability index at distance d, in Vickers HV 30-mm 25 +0,5 0 30 +5 0 ENISO642:1999 2 BSI 04-2000 5 Form of test pieces and their preparation 5.1 Sampling In the absence of specific requirements in the product standard, and unless otherwise agreed on the o

38、rder and regardless of the thickness (or diameter) of the product, the sampling of test piece from the product can be made: either by hot rolling or forging of test piece with30mm to32mm diameter; or by machining of test piece with diametermm whose axis shall be at least atmm from the surface produc

39、t (seeFigure 1). In case of products from continuous casting, a minimum reduction ratio8:1 is recommended before sampling. In all the forming processes preceding the machining of the test piece, the deformation of the product from all sides should be as uniform as possible. In the case of a separate

40、ly cast reference test piece, the original cross section before deformation must be at least three times that corresponding to the required diameter of30mm to32mm. By special agreement, the test piece can be obtained by a suitable casting process and tested in the as-cast condition. The flats of the

41、 test piece shall have their axes at approximately the same distance from the product surface (seeFigure 1). For this purpose, the test piece shall be marked so that its position in the round bar can be clearly recognized. 5.2 Dimensions 5.2.1 The test piece shall consist of a round bar machined to

42、a diameter of25mm and a length of100mm. 5.2.2 The end of the test piece which will not be quenched shall be30mm to32mm or25mm in diameter, depending upon the form of that end. Two examples, test pieces with a flange or an undercut (to permit rapid centring and fitting in position for the quenching o

43、peration by means of an appropriate support) are shown inFigure 2. 5.2.3 The test piece shall, if necessary, be marked (on the end opposite to the end to be quenched) to enable its position to be identified in relation to the original product. 5.3 Heat treatment Unless otherwise agreed, the test pie

44、ce shall be normalized before machining and quenching. The normalizing process shall be carried out at the average temperature within the range specified in the material standard. If the material standard does not specify a temperature for normalizing, the normalizing temperature shall be subject to

45、 special agreement or duly selected by the testing department.The holding time at normalizing temperature shall bemin. The heat treatment shall be carried out in each case in such a way that the finish-machined test piece shows absolutely no traces of decarburization. 5.4 Machining The cylindrical s

46、urface of the test piece shall be machined by fine turning; the surface of the test piece end to be quenched shall have a reasonably fine finish, preferably obtained by fine grinding, and should be free from burrs (seeFigure 2). 25 +0,5 0 20 +5 0 30 +5 0 ENISO642:1999 BSI 04-2000 3 6 Apparatus The a

47、pparatus consists of a device for quenching the test piece. 6.1 The quenching device consists essentially of a means of suddenly inducing the water jet to impinge onthe end of the test piece to be quenched. This can be realized e.g., by a quick action tap and a system toadjust the flow rate of the w

48、ater or a disc allowing the water jet to be released and cut off rapidly (seeFigure 3). In the case of a quick action tap the length of the water supply pipe behind the tap shall be at least50mm in order to ensure non-turbulent water flow. 6.2 The relative positions of the end of the water supply pi

49、pe and the test piece support shall be such thatthe distance between the end of the water supply pipe and the test piece end to be quenched is(12,5 0,5) mm (seeFigure 3). 6.3 The test piece support shall allow precise centring of the test piece above the end of the water supply pipe and the holding of it in position during spraying. It shall be dry while the test piece is being placed in position; the test piece shall be protected from water splashes while it is being placed