ARMY MIL-STD-1895 B-1998 RADIOGRAPHIC REFERENCE STANDARDS AND RADIOGRAPHIC PROCEDURES FOR PARTIAL-PENETRATION ALUMINUM WELDS《局部穿透铝焊接射线参考标准及放射线程序》.pdf

1、3 L MIL-STD-189SB m 9999933 O502464 903 m I INCH-POUND I MIL-STD- 1895B(AT) 26 June 1998 SUPERSEDING 20 October 1986 MIL-STD-1895A DEPARTMENT OF DEFENSE STANDARD PRACTICE RADIOGRAPHIC REFERENCE STANDARDS AND RADIOGRAPHIC PROCEDURES FOR PARTIAL-PENETRATION ALUMINUM WELDS AMSC N/A AREANDTI DISTRIBUTIO

2、N STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-STD-1895B m 9999911 0502465 848 m . FOREWORD 1. This standard is approved for use by the U.S. Army Tank-automotive and Armament

3、s Command, Department of the Amy, and is available for use by all Departments and Agencies of the Department of Defense. 2. This document contains selected radiographs illustrating various types and degrees of discontinuities occurring in partial-penetration aluminum welds. It also contains instruct

4、ional data concerning radiographic inspection of this type of weldment. 3. It is intended that this document provide the following: a. A weld discontinuity severity range for designers to select standards for acceptance inspection. b. Reference standards for acceptance personnel to evaluate the qual

5、ity of production weldment s. c. Guide lines for radiographers to effectively accomplish radiographic examination of partial-penetration welds. 4. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to:

6、 U.S. Army Tank-automotive and Armaments Command, ATTN: AMSTA-TR-E/BLUE, Warren, MI 48397-5000, by using the Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document, or by letter. 11 Provided by IHSNot for ResaleNo reproduction or networking permitted witho

7、ut license from IHS-,-,-PARAGFLU“ CONTENTS PAGE FOREWO RD ii . 1 . SCOPE 1 1.1 Scope 1 1.2 Use of radiographs 1 . . 2 . APPLICABLE DOCUMENTS 2 2.1 General 2 2.2 Government documents 2 2.3 Non-Government publications 2 2.4 Order of precedence 3 . 3 . DEFINITIONS . 4 3.1 Metallographic cross . section

8、s 4 3.2 Partial penetration joint design . 4 3.3 Penetrameter / Image quality indicator . 4 3.4 Nondestructive testing terms and definitions . 4 4 . 4.1 4.1.1 4.1.2 4.1.3 4.2 4.3 4.4 GENEML REQUIREMENTS Radiographic frequency Anglebe am . Penetrameter requirements Acceptance standards Discontinuity

9、types Discontinuitygraduig Radiographic location . 5 . DETAILEDREQUIREMENTS . 7 5.1 Application of reference standards . 7 5.1.1 Determination of acceptability 7 5.1.2 Quality levels of radiographic sensitivity 7 5.1.3 Rules land2 7 5.1.4 False indications 8 5.2 Inspection records . 8 6 . NOTES . 9

10、6.1 Intendeduse . 9 6.2 Subject (key word) listing . 9 6.3 Changes fiom previous issues 9 . U1 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-FIGURE(S1 8 9 MIL-STD-1895B 9999911 0502467 bL0 MIL-STD- 1895B(AT) FIGURES PAGE) Correct and incorrect radi

11、ographic procedure for joint design (L) 10 11-12 13-14 15-16 17 18-19 Reference standards for fine scattered porosity in aluminum welds Reference standards for coarse scattered porosity in aluminum welds . . Reference standards for linear porosity in aluminum welds Reference standards for gas caviti

12、es in aluminum welds Examples of incomplete penetration correlated with weld cross-sections in aluminum welds . 20 Examples of lack of fusion correlated with weld cross-sections in aluminum welds. 21 Recommended angle beam and film location for typical partial-penetration joints 22-24 Reference stan

13、dards for clustered porosity in aluminum welds . iv Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NIL-STD-1875B 9799711 8502468 557 H 1. SCOPE 1.1 Scope. This standard provides standard reference radiographs and recommended radiographic inspection

14、procedures for partial-penetration weldments in aluminum plate, casting, or forging, 0.5 to 2 inches (i.) (12.70 to 50.80 millimeters (mm) thick. 1.2 Use of radiomaDhs. The reference radiographs comprised in this standard are intended primarily for use on welds made with the gas metal arc welding an

15、d gas tungsten processes and may be manual or machine welded. 1 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-2. APPLICABLE DOCUMENTS 2.1 General. The documents listed below are not necessarily all of the documents referenced herein, but are the on

16、es that are needed in order to fully understand the information provided by this standard. 2.2 Government documents. 2.2.1 Specifications. standards. and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise sp

17、ecified, the issues of the documents which are DoD adopted are those listed in latest issue of the Department of Defense Index of Specifications and Standards (DoDISS) and supplements thereto. STANDARDS DEPARTMENT OF DEFENSE MIL-STD-4 1 O - Nondestructive Testing Personnel Qualification and Certific

18、ation. (Note: Negatives of radiographs illustrated in this standard can be purchased through AMSTA-TR-EBLUE. Requests should be addressed to U.S. Army Tank-automotive and Armaments Command, Attn: AMSTA-TR-BLUE, Warren, MI 48397-5000.) (Unless otherwise indicated, copies of the above specifications,

19、standards, and handbooks are available from the Standardization Document Order Desk, 700 Robbins Avenue, Bddng 4D, Philadelphia, PA 19 1 1 1-5094.) 2.3 Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the is

20、sues of the documents which are DoD adopted are those listed in latest issue of the Department of Defense Index of Specifications and Standards (DoDISS) and supplements thereto. AMERICAN SOCTETY FOR TESTING AND MATERIALS (ASTM) ASTM E142 ASTM E340 - Controlling Quality of Radiographic Testing, Metho

21、d for - Standard Method for Macroetching Metals and Alloys OD Adopted). OD Adopted). 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NIL-STD-1895B 9999911 0502470 105 MIL-STD- 1895B(AT) ASTM E13 16 ASTM E 1742 - Standard Terminology for Nondestruct

22、ive Examinations. - Radiographic Examination, Standard Practice for OD Adopted). (Application for copies should be addressed to the American Society for Testing and Materials, 1 O0 Barr Harbor Drive, West Conshohocken, PA 19428-2959.) 2.4 Order of Precedence. In the event of a conflict between the t

23、ext of this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3 Provided by IHSNot for ResaleNo reproduction or networking permitted withou

24、t license from IHS-,-,-3. DEFINITIONS 3.1 Metallograthic - cross sections. Cross sections through the welds as shown in figures 1 through 8, which are cut perpendicular to the direction of welding, polished and etched as specified in ASTM E340. These samples show internai discontinuity, depth of wel

25、d penetration, weld size, and other characteristics of the weldment. 3.2 Partial-penetration joint desim. The term “partial-penetration joint, as used in this standard is defined as a weld joint containing an intentionally unfused area. Examples of typicai partial-penetration joint designs are shown

26、 in figure 9. 3.3 Penetrameter/Imane Ouality Indicator (IOQ. A strip of metal the same composition as that of the metal being tested, representing a percentage of object thickness and provided with a combination of steps, holes, and/or slots. Its image on a radiograph is used to determine the radiog

27、raphic quality level. It is not intended for use in judging the size nor for establishing acceptance limits of discontinuities. Examples of penetrameters/IQIs are shown in figures 2, 3,4, 5 and 6. 3.4 Nondestructive testinn terms and definitions. Nondestructive testing terms and denitions are as spe

28、cified in ASTM E13 16. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-STD- 1895B(AT) 4. GENERAL REQUIREMENTS 4.1 Radiographic location. Weldments are radiographically inspected in the location specified on the applicable radiographic position

29、chart drawing, component drawing, specification, or contract requirement. Radiographic inspection shall meet the requirements of MIL-STD-410 and ASTM E1742. 4.1.1 Radiographic freauency. Establishing radiographic fiequency of spot checking of weldments shail be accomplished in accordance with a Gove

30、rnment approved quaiity assurance plan. The frequency of spot-checking and selection of the applicable standard has historically been based on the importance of the particular joint. 4.1.2 Ande beam. Radiographic inspection of partial-penetration welds requires special consideration of joint design

31、when selecting the radiation angle. The angie employed shall insure adequate coverage of the weld with minimal interference from the normally unfsed area. Generaily this can be achieved by directing the X-ray beam such that any possible incomplete penetration at both roots would b,e separated on the

32、 film by at least O. 125 in. (3.18 mm). Figure 1 illustrates the radiographic results of a correct and incorrect radiation angle. If a radiographic position chart is not available, the recommended procedures shown on figure 9 shaii be used as a guide. 4.1.3 PenetrameterDI requirements. Each penetram

33、eterDQ1 shall be produced with three holes, one of which shall be a diameter equal to twice the PenetrameterhQI thickness (2T). PenetrameterhQI requirements are given in ASTM E142 and ASTM E1742. 4.2 Acceptance standards. Designation of acceptance standards for each type of discontinuity illustrated

34、 in the reference standards shall be made by the design activity and approved by the Government procurement agency. The specific level of acceptance shail be designated by the “Standard Level” which is the minimum acceptance level for that discontinuity. The standard level shall be documented on the

35、 applicable radiographic position chart, drawing or contract requirement. 4.3 Discontinuity tpes. With the exception of cracks, the common discontinuities experienced in partial-penetration aluminum weldments made are shown in the reference standards forming part of this document. These discontinuit

36、ies are described below and in figures 2 through 6. Ail cracks have historically been rejected and any deviation from this procedure will require authorization from the Government procuring activity. a. Scattered porosity fine and coarse). This flaw consists of scattered voids formed by gasses faili

37、ng to escape during weld metal solidification. On the radiograph these discontinuities are dark round or elongated spots of varying size and density. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-STD-L95B m 99999LL 0502473 914 MIL-STD-l895B(A

38、T) The average size of fine porosity is 0.03 1 in. (0.79 mm) in diameter and that of coarse porosity is 0.063 in. (1.59 mm) in diameter. b. Clustered Dorositv. Clustered porosity appears the same as scattered porosity except that the pores are concentrated in one area, generally at the start of a be

39、ad or an interrupted arc. c. Linear porositv. The type most common in partial-penetration welds results fiom expanding gasses generated in the normally unfsed area. The cavities are linearly distributed at the root of the weld deposit and generally range fiom 0.03 1 in. (0.79 mm) in diameter to 0.06

40、3 in. (1.59 mm) in diameter. d. Gas cavities. This discontinuity generally results fiom inadequate shielding gas or severe contamination of the gas. It appears the same as scattered porosity except that the average cavity size is approximately 0.125 in. (3.18 mm) in diameter. e. Incorndete (inadeaua

41、te) penetration. In partial penetration welds this discontinuity consists of a linear root void in excess of the untused area normally present in this type of joint. It appears on the radiograph as a straight dark line at either root or at both roots. When present at both roots the two images should

42、 be separated if properly radiographed. f. Lack of fusion. Lack of fusion is failure of the weld metal to fuse completely with the base metal or with the preceding bead. Lack of fusion between the weld metal and base metal is most common in aluminum welds and is generally associated with incomplete

43、penetration near the root of the weld. Examples of this are illustrated in figures 7 and 8. This discontinuity is very difcult to detect radiographically due to its hair-line condition and interference fiom the incomplete penetration void. 4.4 Discontinuitv mading. Discontinuity severity grading of

44、the reference standards was selected to extend fiom standard 1, which represents a high-quality weld, to that of standard 5, which is indicative of poor workmanship and is usually rejected in commercial practice. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license

45、from IHS-,-,-MIL-STD-L95B m 99999LL 0502474 850 m 5. DETAJLED REQUIREMENTS 5.1 Apolication of reference standards. 5.1.1 Determination of acceptability. Acceptability of production welds shail be determined by directly comparing the production radiograph with the designated reference standard for ea

46、ch type of discontinuity. In general the extent of discontinuity exhibited in the designated standard will be permitted throughout the length of any particular weld joint provided that the discontinuity content in any weld length equal to that of the reference standard does not exceed that shown in

47、the standard. Exceptions to this are required for incomplete penetration and lack of fusion since acceptability of those discontinuities is based on material thickness. The examples shown in figures 7 and 8 are for illustration purposes only; the evaluation is described in 5.1.3. 5.1.2 Ouality level

48、 of radiographic sensitivity. Figures 2,3,4, 5 and 6 illustrate the radiographic image quality level of 2-1T. ASTM E1742 defines this formula as follows: Radiographic quality level 2-1T PenetrameterAQI designation 1 Maximum penetrameterAQ1 thickness 2% expressed as a percentage of material thickness

49、, T. Minimum penetrameterDQ1 hole diameter expressed as a multiple of thickness of penetrameterAQ1 1T Equivalent penetrameterAQ1 sensitivity expressed as a percentage of the specimen thickness in which a 2T hole would be cleariy visible under the same radiographic conditions 1.4% 5.1.3 Rules 1 and 2. Incomplete penetration and lack of fusion shall be judged by image width