SANS 1338-2008 Abrasion-resisting white cast irons《耐磨白口铸铁》.pdf

1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA

2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any

3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-20958-2 SANS 1338:2008Edition 1.1Any reference to SABS 1338 is deemedto be a reference to this standard(Government Notice No. 1373 of 8 No

4、vember 2002)SOUTH AFRICAN NATIONAL STANDARD Abrasion-resisting white cast irons Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 1338:2008 Editio

5、n 1.1 Table of changes Change No. Date Scope Amdt 1 2008 Amended to change the designation of SABS standards to SANS standards, to update the definition of “acceptable” and to update referenced standards. Acknowledgement Standards South Africa wishes to acknowledge the valuable assistance derived fr

6、om publications of the following organizations: American Society for Testing and Materials British Standards Institution Foreword This South African standard was approved by National Committee StanSA TC 5120.20E, Engineering materials Ferrous metals, in accordance with procedures of Standards South

7、Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in April 2008. This document supersedes SABS 1338:1981 (first edition). A vertical line in the margin shows where the text has been technically modified by amendment No. 1. SANS 1338:2008 Edition 1.1 1 Contents

8、Page Acknowledgement Foreword 1 Scope . 3 2 Definitions 3 3 Requirements . 4 4 Marking 7 5 Sampling and compliance with the specification . 8 6 Inspection and methods of test 9 6.1 Inspection 9 6.2 Chemical analysis . 9 6.3 Hardness test 9 6.4 Other tests . 9 Appendix A Applicable standards 10 Appen

9、dix B Notes to purchasers . 10 Appendix C The metallurgical structure of abrasion-resisting white cast irons in the as-cast and heat-treated conditions . 12 Appendix D The principles governing the use of abrasion-resisting white cast irons, and some typical uses . 14 SANS 1338:2008 Edition 1.1 2 Thi

10、s page is intentionally left blank SANS 1338:2008 Edition 1.1 3 Abrasion-resisting white cast irons 1 Scope 1.1 This specification covers the requirements for three categories of abrasion-resisting white cast irons. The categories are the following: 1.1.1 Category 1 comprises a group of unalloyed an

11、d low alloy irons in three compositions designated 1A, 1B, and 1C. 1.1.2 Category 2 comprises two groups of nickel-chromium irons, namely a) a low-chromium, low-silicon type in two compositions designated 2A and 2B; and b) a high-chromium, high-silicon type in three compositions designated 2C, 2D, a

12、nd 2E. 1.1.3 Category 3 comprises three groups of high-chromium irons, namely a) a 14-17 % chromium type in two compositions designated 3A and 3B; b) a 17-22 % chromium type in one composition designated 3C; and c) a 22-28 % chromium type in two compositions designated 3D and 3E. NOTE a) The standar

13、ds referred to in the specification are listed in appendix A. b) Requirements that must be specified by the purchaser and those that must or may be agreed upon between the manufacturer and the purchaser are given in appendix B. 2 Definitions For the purposes of this specification the following defin

14、itions shall apply: abrasion-resisting white cast iron one of a family of alloyed cast irons which contains silicon, alloying elements and at least 1,8 % carbon, and which has a microstructure in which graphite is absent, and that consists essentially of carbides acceptable acceptable to the authori

15、ty administering the standard, or to the parties concluding the purchase contract, as relevant Amdt 1 SANS 1338:2008 Edition 1.1 4 cast batch a) fettled castings that have been poured from one furnace load and that have been submitted to the same heat treatment, where necessary b) fettled castings p

16、oured continuously during a maximum period of 2 h from the same melting unit which has been consecutively charged with the same percentages and types of materials, and that have been submitted to the same heat treatment, where necessary defective a casting or a test specimen that fails in one or mor

17、e respects to comply with the appropriate requirements of the specification lot not more than 10 000 castings of the same pattern and heat-treated condition, from one batch, submitted at any one time for inspection and testing 3 Requirements 3.1 General The castings shall be accurately moulded in ac

18、cordance with the pattern or drawings supplied by the purchaser, shall be within the dimensional tolerances agreed upon between the purchaser and the supplier, and shall be properly fettled and cleaned. The castings shall be free from distortion and defects that would adversely affect their use but,

19、 by agreement between the manufacturer and the purchaser, any founding defects may be rectified by an agreed method, provided that the rectification does not interfere with the ultimate use of the castings. 3.2 Chemical composition The chemical composition of an alloy, determined in accordance with

20、6.2, shall comply with the requirements given in table 1, appropriate to the alloy designation specified by the purchaser. Table 1 Chemical composition 1 2 3 4 5 6 7 8 9 10 Carbon Silicon Manganese Nickel Chromium Molybdenum Copper Phosphorus Sulphur Designation % % % % % % %, max. %, max. %, max. 1

21、A 1B 1C 2,43,4 2,43,4 2,43,0 0,51,5 0,51,5 0,51,5 0,40,8 0,40,8 0,40,8 2,0 max. 2,0 max. 2,0 max. 0,15 0,5 0,15 2A 2B 2C 2D 2E 2,73,2 3,23,6 2,42,8 2,83,2 3,23,6 0,30,8 0,30,8 1,52,2 1,52,2 1,52,2 0,40,8 0,40,8 0,40,8 0,40,8 0,40,8 3,0*5,5 3,0*5,5 4,06,0 4,06,0 4,06,0 1,5+2,5 1,5+2,5 8,010,0 8,010,0

22、 8,010,0 0,5 max 0,5 max. 0,5 max 0,5 max 0,5 max 0,3 0,3 0,3 0,3 0,3 0,15 0,15 0,15 0,15 0,15 3A#3B#3C#3D#3E#2,43,0 3,03,6 2,23,0 2,42,8 2,83,2 1,0 max. 1,0 max. 1,0 max. 1,0 max. 1,0 max. 0,51,5 0,51,5 0,51,5 0,51,5 0,51,5 1,0 max. 1,0 max. 1,5 max. 1,0 max. 1,0 max. 1417 1417 1722 2228 2228 2,5 m

23、ax. 13,0 3,0 max. 1,5 max. 1,5 max. 1,2 1,2 1,2 1,2 1,2 0,1 0,1 0,1 0,1 0,1 0,06 0,06 0,06 0,06 0,06 * For a section of thickness less than 15 mm the nickel content may be reduced to 2,5 % min. +For a section of thickness greater than 150 mm, the chromium content may be increased to 3,5 % max. #For

24、optimum properties, some adjustment to the degree of alloying (but within the ranges quoted) is necessary since dimensions of castings vary. This is because the rate of cooling affects the microstructure which is sensitive to section sizes. Where sections of thickness less than 10 mm are to be cast,

25、 extreme metal fluidity is required and the total carbon content may be increased to 3,4 % or the silicon content to 1,5 %. 5 SANS 1338:2008 Edition 1.1SANS 1338:2008 Edition 1.1 6 3.3 Hardness Unless alternative minimum and maximum hardness limits are agreed upon between the manufacturer and the pu

26、rchaser, the modified Brinell hardness of a casting, determined in accordance with 6.3, shall be at least the appropriate value given in table 2. Table 2 Hardness 1 2 3 Hardness Designation Condition HBW, min. 1A 1B 1C As cast As cast Heat-treated 400* 400* 250* 2A 2B 2C 2D 2E Heat-treated Heat-trea

27、ted Heat-treated Heat-treated Heat-treated 500+550+500+550+600+3A 3B 3C 3D 3E As cast As cast As cast As cast As cast 450 500 450 400 450 * In the case of category 1 castings having a section thickness greater than 50 mm, minimum hardness values up to 50 Brinell points lower than those specified in

28、table 2 shall be permitted. +In the case of category 2 castings having a section thickness greater than 125 mm, minimum hardness values up to 50 Brinell points lower than those specified in table 2 shall be permitted. 3.4 Heat treatment 3.4.1 Unless otherwise agreed upon between the manufacturer and

29、 the purchaser, castings designated 1A1)and 1B shall be supplied in the as-cast condition. Castings designated 1C shall be supplied in the heat-treated condition to provide some degree of machinability2), the cycle selected being at the discretion of the manufacturer i n order to achieve compliance

30、with the hardness requirements. 1) The low phosphorus iron designated 1A is to be preferred where resistance to impact loading is required in a category 1 casting. 2) The abrasion resistance is correspondingly reduced because of this. SANS 1338:2008 Edition 1.1 7 3.4.2 Castings designated 2A and 2B

31、shall be supplied in one of the following heat-treated conditions, as agreed upon between the manufacturer and the purchaser: a) heat-treated at 275 25 C for 12-16 h followed by air-cooling or furnace-cooling; or b) heat-treated at 450 25 C for 4-6 h followed by air-cooling or furnace-cooling, and t

32、hen heat-treated at 275 25 C for 12-16 h followed by air-cooling or furnace-cooling. NOTE Where maximum resistance to repeated impact is required, heat treatment (b) is recommended. 3.4.3 Castings designated 2C, 2D, and 2E shall be supplied in one of the following heat-treated conditions, as agreed

33、upon between the manufacturer and the purchaser: a) heat-treated at 800 25 C for 6-12 h followed by air-cooling or furnace-cooling; or b) heat-treated at 800 25 C for 6-12 h followed by air-cooling or furnace cooling, and then heat-treated at 275 25 C for 12-16 h followed by air-cooling or furnace-c

34、ooling. NOTE Where maximum resistance to repeated impact is required, heat treatment (b) is recommended. 3.4.4 Castings designated 3A, 3B, 3C, 3D and 3 E shall be supplied in the as-cast or the heat-treated condition, as agreed upon between the manufacturer and the purchaser. NOTE The improved prope

35、rties brought about by heat treatment can be varied to suit the application. Recommended heat treatments and subsequent hardness levels are given in appendix C. 3.5 Additional requirements Any additional requirements, such as the quality of the castings as assessed by the microstructure, shall be as

36、 agreed upon between the manufacturer and the purchaser. NOTE Information that may suggest specific additional requirements can be found in appendix D. 3.6 Test certificates When so required by the purchaser, each lot (consignment) shall be accompanied by a certificate from the supplier that include

37、s the results of tests (carried out in accordance with section 6 on samples taken in accordance with section 5) covering all the appropriate requirements for the castings. 4 Marking 4.1 The following information shall be cast3)(or shall appear in legible and indelible marking) on each casting or, if

38、 the size or shape of castings prevents this, shall appear in legible and indelible marking on the container in which the castings are packed: a) the manufacturers name, trade name, trade mark, or other identifying mark; b) the designation; c) where so required by the purchaser, and if practicable,

39、the batch identification. 3) Warning: Cracks can be propagated from cast identification marks if the marks introduce stress concentration and are placed in a position where high stresses will be present in service. SANS 1338:2008 Edition 1.1 8 5 Sampling and compliance with the specification NOTE Th

40、is section applies to the sampling for inspection and testing before acceptance or rejection of single lots (consignments) in cases where no information about the implementation of quality control or testing during manufacture is available to help in assessing the quality of the lot. It is also used

41、 as the procedure for adjudicating in cases of dispute. 5.1 The following sampling procedure shall be applied in determining whether a lot complies with the relevant requirements of the specification. The samples so taken shall be deemed to represent the lot for the respective properties. 5.1.1 Samp

42、le for inspection Draw at random from the lot the number of castings given in column 2 of table 3 relative to the appropriate lot size given in column 1. Table 3 Sample sizes4)1 2 3 Sample for inspection Lot size Sample sizescastings castings Acceptance number 3 26 91 25901503 13 20 0 1 2 151 281 50

43、1 2805001 20032 50 80 3 5 7 1 201 3 201 3 20010 000125 200 10 14 5.1.2 a) Sample for chemical analysis. During the pouring of the castings in the lot, cast a test block of convenient size. Alternatively take one casting at random from the lot. b) Sample for hardness testing. Cast, simultaneously wit

44、h the castings in the lot, a test piece or test pieces, or select a specific area of a finished casting, for hardness testing, as agreed upon between the manufacturer and the purchaser. In those cases where a separate test piece or pieces are cast, the cast piece(s) must have a thickness similar to

45、the ruling section of the castings being tested and, where relevant, must have been heat-treated along with the castings. The number of test pieces or castings shall be by agreement between the manufacturer and the purchaser. c) Sample for testing compliance with additional requirements 1) Microstru

46、cture. Use the test piece or test pieces cast in accordance with 5.1.2(b) or select a specific area of a finished casting, as agreed upon between the manufacturer and the purchaser, from which to cut a specimen. The number of test pieces or castings shall be by agreement between the manufacturer and

47、 the purchaser. 4) This sampling table is based on the data given in ISO 2859-1 for single sampling for normal inspection (level II) with an acceptable quality level of 4,0 (which has been selected as being the AQL most suitable for any type of abrasion-resisting white iron casting). Amdt 1 SANS 133

48、8:2008 Edition 1.1 9 2) Additional requirements other than for microstructure. Use the sampling procedure and number of samples agreed upon between the manufacturer and the purchaser. NOTE In the case of heat-treated castings the manufacturer shall have the right to re-heat-treat the castings and te

49、st pieces and submit them for re-testing, should the original test results (other than of chemical analysis) have failed to comply with the appropriate requirements. Only one re-heat treatment shall be permitted. 5.2 Compliance with the specification The lot shall be deemed to comply with the requirements of the specification if a) on inspection of the sample taken in accordance with 5.1.1, the number of defectives found does not exceed the appropriate accep