AWS C1.1M/C1.1:2019

An American National Standard

Recommended Practices for Resistance Welding

AWS C1.1M/C1.1:2019

An American National Standard

Approved by the American National Standards Institute

January 25, 2019

Recommended Practices for Resistance Welding

6th Edition

Supersedes AWS C1.1M/C1.1:2012

Prepared by the American Welding Society (AWS) C1 Committee on Resistance Welding

Under the Direction of the AWS Technical Activities Committee

Approved by the AWS Board of Directors

Abstract

This Recommended Practices is a collection of data and procedures that are intended to assist the user in setting up resist- ance welding equipment to produce resistance welded production parts. While the recommendations included are not expected to be final procedures for every production part or every welding machine, they serve as starting points from which a user can establish acceptable welding machine settings for specific production welding applications.

In some cases, recommended machine data is not available. In these instances, some description of the process is given to assist the reader in determining if the process might be suitable for the application.

AWS C1.1M/C1.1:2019

AWS C1.1M/C1.1:2019

ISBN Print: 978–1–64322–028–4

ISBN PDF: 978–1–64322–029–1

©2019 by American Welding Society

All rights reserved Printed in the United States of America

Photocopy Rights. No portion of this standard may be reproduced, stored in a retrieval system, or transmitted in any form, including mechanical, photocopying, recording, or otherwise, without the prior written permission of the copyright owner.

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Statement on the Use of American Welding Society Standards

All standards (codes, specifications, recommended practices, methods, classifications, and guides) of the American Welding Society (AWS) are voluntary consensus standards that have been developed in accordance with the rules of the American National Standards Institute (ANSI). When AWS American National Standards are either incorporated in, or made part of, documents that are included in federal or state laws and regulations, or the regulations of other governmen- tal bodies, their provisions carry the full legal authority of the statute. In such cases, any changes in those AWS standards must be approved by the governmental body having statutory jurisdiction before they can become a part of those laws and regulations. In all cases, these standards carry the full legal authority of the contract or other document that invokes the AWS standards. Where this contractual relationship exists, changes in or deviations from requirements of an AWS stand- ard must be by agreement between the contracting parties.

AWS American National Standards are developed through a consensus standards development process that brings together volunteers representing varied viewpoints and interests to achieve consensus. While AWS administers the proc- ess and establishes rules to promote fairness in the development of consensus, it does not independently test, evaluate, or verify the accuracy of any information or the soundness of any judgments contained in its standards.

AWS disclaims liability for any injury to persons or to property, or other damages of any nature whatsoever, whether special, indirect, consequential, or compensatory, directly or indirectly resulting from the publication, use of, or reliance on this standard. AWS also makes no guarantee or warranty as to the accuracy or completeness of any information pub- lished herein.

In issuing and making this standard available, AWS is neither undertaking to render professional or other services for or on behalf of any person or entity, nor is AWS undertaking to perform any duty owed by any person or entity to someone else. Anyone using these documents should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable care in any given circumstances. It is assumed that the use of this standard and its provisions is entrusted to appropriately qualified and competent personnel.

This standard may be superseded by new editions. This standard may also be corrected through publication of amend- ments or errata, or supplemented by publication of addenda. Information on the latest editions of AWS standards includ- ing amendments, errata, and addenda is posted on the AWS web page (www.aws.org). Users should ensure that they have the latest edition, amendments, errata, and addenda.

Publication of this standard does not authorize infringement of any patent or trade name. Users of this standard accept any and all liabilities for infringement of any patent or trade name items. AWS disclaims liability for the infringement of any patent or product trade name resulting from the use of this standard.

AWS does not monitor, police, or enforce compliance with this standard, nor does it have the power to do so.

Official interpretations of any of the technical requirements of this standard may only be obtained by sending a request, in writing, to the appropriate technical committee. Such requests should be addressed to the American Welding Society, Attention: Managing Director, Standards Development, 8669 NW 36 St, # 130, Miami, FL 33166 (see Annex B). With regard to technical inquiries made concerning AWS standards, oral opinions on AWS standards may be rendered. These opinions are offered solely as a convenience to users of this standard, and they do not constitute professional advice. Such opinions represent only the personal opinions of the particular individuals giving them. These individuals do not speak on behalf of AWS, nor do these oral opinions constitute official or unofficial opinions or interpretations of AWS. In addi- tion, oral opinions are informal and should not be used as a substitute for an official interpretation.

This standard is subject to revision at any time by the AWS C1 Committee on Resistance Welding. It must be reviewed every five years, and if not revised, it must be either reaffirmed or withdrawn. Comments (recommendations, additions, or deletions) and any pertinent data that may be of use in improving this standard are requested and should be addressed to AWS Headquarters. Such comments will receive careful consideration by the AWS C1 Committee on Resistance Welding and the author of the comments will be informed of the Committee’s response to the comments. Guests are invited to attend all meetings of the AWS C1 Committee on Resistance Welding to express their comments verbally. Procedures for appeal of an adverse decision concerning all such comments are provided in the Rules of Operation of the Technical Activities Committee. A copy of these Rules can be obtained from the American Welding Society, 8669 NW 36 St, # 130, Miami, FL 33166.

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Personnel

AWS C1 Committee on Resistance Welding

B. Kelly, Chair Kelly Welding Solutions PC

W. F. Qualls, Vice Chair Consultant

M. Diaz, Secretary American Welding Society

T. W. Alexander Centerline (Windsor) Ltd.

W. H. Brafford Consultant

R. K. Cohen Weld Computer Corporation

M. Cubert Space Exploration Technologies

R. Michelena T. J. Snow Company, Inc.

D. Wellman Obara Corporation

Advisors to the AWS C1 Committee on Resistance Welding

B. J. Bastian Benmar Associates

K. Hofman Roman Engineering Services

1. Kimchi Edison Welding Institute

   D. F. Maatz R&E Engineering Services

2. S. Scotchmer Huys Industries Limited

D. C. Sorenson Entron Controls, LLC

M. Tumuluru U.S. Steel

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Foreword

This foreword is not part of this standard, but is included for informational purposes only.

The data contained in these Recommended Practices have been compiled by the AWS Committee on Resistance Welding, by reviewing the data in the previous documents, by canvassing users of the resistance welding processes and correlating the data thus obtained. The resulting welding schedules shown in the tables were circulated for comments and, in addi- tion, some tests were conducted to ascertain that welds of the specified strengths could be obtained.

The present edition of Recommended Practices represents an updated combination and extension of data presented in the previous edition of AWS C1.1M/C1.1:2012, Recommended Practices for Resistance Welding. Practices for new materials have been added and practices for materials which are not currently resistance welded in commercial production have been deleted. The new materials include high-strength low-alloy steels, both coated and uncoated.

The AWS C1 Committee on Resistance Welding has prepared these Recommended Practices in the hope that they will serve as an incentive for industry to develop methods and procedures improving upon the practice presented herein; which will permit the raising of quality and performance standards. If this is achieved, the Committee will have been amply repaid for the time and effort it has devoted to this work.

A vertical line in the margin and underlined text in clauses, tables, or figures indicates an editorial or technical change from the 2012 edition.

Comments and suggestions for the improvement of this standard are welcome. They should be sent to the Secretary, AWS C1 Committee on Resistance Welding, American Welding Society, 8669 NW 36 St, Miami, FL 33166.

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Table of Contents

Page No.

Personnel v

Foreword vii

List of Tables xi

List of Figures xiii

1. General Requirements 1

   1. Scope 1

   2. Units of Measurement 1

   3. Safety 1

2. Normative References 2

3. Terms and Definitions 2

4. Resistance Spot and Seam Welding 3

   1. Uncoated Carbon and Low-Alloy Steels 3

   2. Coated Carbon and Low-Alloy Steels 12

   3. Aluminum Alloys 14

   4. Stainless Steels, Nickel, Nickel-Base, and Cobalt-Base Alloys 20

   5. Copper and Copper Alloys 23

   6. Titanium and Titanium Alloys 23

   7. Welding Data Comments and Discussions Applicable to Various Metals 27

   8. Weld Discrepancies and Causes 46

   9. Weld Quality and Mechanical Property Tests 48

5. Projection Welding 70

   1. Introduction 70

   2. Embossed Projection Welding 72

   3. Solid Projection Welding 78

   4. Multiple Projection Welding 80

   5. Weld Quality and Mechanical Property Tests 80

6. Flash Welding 80

   1. Introduction 80

   2. Equipment 81

   3. Welding Variables 85

   4. Welding Variable Measurements 88

   5. Classification of Steels for Flash Welding 89

   6. Joint Preparation and Cleaning 89

   7. Welding Schedules 91

   8. Weld Discrepancies and Causes 91

   9. Weld Quality and Mechanical Property Tests 94

7. Upset Welding 95

   1. Introduction 95

   2. Equipment 95

   3. Welding Variables 95

   4. Joint Preparation and Cleaning 95

      AWS C1.1M/C1.1:2019

   5. Welding Parameters 95

   6. Weld Quality and Mechanical Property Tests 95

8. Weld Bonding 96

   1. Introduction 96

   2. Aluminum Alloys 96

   3. Other Metals 97

   4. Weld Bonding Quality and Mechanical Property Tests 99

9. Equipment Monitoring and Maintenance 100

Annex A (Informative)—Informative References 111

Annex B (Informative)—Requesting an Official Interpretation on an AWS Standard 113

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List of AWS C1 Documents for Resistance Welding 115

List of Tables

Table Page No.

1. Spot-Welding Parameters for Bare, Galvanneal, and Galvanized Low-Carbon Steel

   <350 MPa [72 ksi] Ultimate Tensile Strength 5

2. Pulsation Spot-Welding Parameters for Low-Carbon Steel 6

3. Seam—Welding Parameters for Bare, Galvanneal, and Galvanized Low-Carbon Steel

   >300 MPa [44 ksi] Ultimate Tensile Strength 7

4. Spot-Welding Parameters for Bare, Galvanneal, and Galvanized Low-Carbon Steel

   350~700 MPa [50–100 ksi] Ultimate Tensile Strength 8

5. Spot-Welding Parameters for Bare, Galvanneal, and Galvanized Low-Carbon Steel

   >700 MPa [<101 ksi] Ultimate Tensile Strength 9

6. Spot-Welding Parameters for Low-Alloy and Medium-Carbon Steels 10

7. Electrode Materials for Resistance Welding 11

8. Basic Aluminum Alloy Groups 15

9. Resistance Weldability Chart for Commonly Used Combinations of Aluminum Alloys

   (Based On Equal Thickness) 16

10. Recommended Spot-Weld Spacing, Edge Distance, Overlap, and Distance between Rows of

    Welds for Aluminum and Its Alloys 19

11. Spot-Welding Parameters for Aluminum Alloys on Standard Single-Phase A-C Type Equipment 20

12. Spot-Welding Parameters for Aluminum Alloys on Single-Phase A-C Slope Control

    Type Machines 21

13. Spot-Welding Parameters for Aluminum Alloys on Three-Phase Rectifier-Type Equipment 22

14. Spot-Welding Parameters for Aluminum Alloys on Three-Phase Frequency Converter-Type

    Equipment (Single Impulse Welds) 24

15. Spot-Welding Parameters for Stainless Steels 25

16. Pulsation Spot-Welding Parameters for Stainless Steels 26

17. Seam-Welding Parameters for Stainless Steels 27

18. Spot-Welding Parameters for Annealed Nickel–Copper Alloy on Single-Phase Equipment 28

19. Spot-Welding Parameters for Annealed Nickel–Copper Alloy on Three-Phase Frequency

    Converter Machines 29

20. Seam-Welding Parameters for Annealed Nickel–Copper Alloy on Single-Phase Equipment 30

21. Seam-Welding Parameters for Annealed Nickel–Copper Alloy on Three-Phase Frequency

    Converter Machines 33

22. Spot-Welding Parameters for Annealed Nickel–Chromium Alloy 600 on Single-Phase Equipment 34

23. Spot-Welding Parameters for Annealed Nickel–Chromium Alloy X750 on Single-Phase

    Equipment 35

24. Spot-Welding Parameters for Annealed Nickel–Chromium Alloy X750 on Three-Phase

    Frequency Converter Machines 36

25. Spot-Welding Parameters for Annealed Nickel–Chromium Alloy X750 on Three-Phase

    Dry Disk Rectifier Machines 37

26. Seam-Welding Parameters for Annealed Nickel–Chromium Alloy X750 on Single-Phase

    Equipment 38

27. Seam-Welding Parameters for Annealed Nickel–Chromium Alloy X750 on Three-Phase

    Frequency Converter Machines 39

28. Roll-Spot-Welding Parameters for Annealed Nickel–Chromium Alloy X750 on Three-Phase

    Dry Disk Rectifier Machines 40

29. Spot-Welding Parameters for Annealed Nickel on Single-Phase Equipment 41

    AWS C1.1M/C1.1:2019

30. Spot-Welding Parameters for Nickel–Iron–Chromium Alloys 42

31. Seam-Welding Parameters for Nickel–Iron–Chromium Alloys 42

32. Seam-Welding Parameters for Cobalt–Chromium–Nickel Alloys 42

33. Spot-Welding Parameters for Various Copper Alloys 43

34. Spot-Welding Parameters for Titanium Alloy 6% Al–4% V 43

35. Variation of Current Density and Unit Force Due to Lack of Electrode Tip Maintenance 44

36. Spot-Welding Parameters for Various Thickness Combinations and Arrangements of

    Uncoated and Coated-Carbon and Low-Alloy Steels 45

37. Projection and Die Geometries for Welding a Range of Heavy-Gauge Steels 73

38. Process Requirements for Projection Welding a Range of Heavy-Gauge Steels 74

39. Punch Design Data for Low-Carbon Steel Projections 75

40. Die Button Design Data for Low-Carbon Steel Projections 76

41. Punch and Die Design Data for Forming Projections on Stainless Steel 77

42. Projection Welding Parameters for Low-Carbon Steel 78

43. Projection Welding Parameters for Galvanized Low-Carbon Steel 78

44. Projection Welding Parameters for Stainless Steels 79

45. Projection Designs and Process Requirements for Annular Projection Welding Some

    Representative Light-Gauge Steels 79

46. Projection Welding Design Data for Stainless Steels 82

47. Embossed Projections for Low-Carbon Steel 83

48. Process Requirements for Cross-Wire Welding a Range of Thicknesses of Hot- and

    Cold-Drawn Steel Wires 84

49. Data for Flash Welding of Tubing and Flat Sheets 92

50. Data for Flash Welding of Solid Round, Hex, Square, and Rectangular Bars 93

51. Weld-Bonding Surface Preparation for Aluminum Alloys by Low-Voltage Anodizing 97

52. Comparison between Resistance Spot-Welding and Weld-Bonding of Aluminum Alloys 98

53. Typical Spot-Welding Parameters for 1.6 mm [0.063 in] Thick 7075-T6 Aluminum Treated

    with a Low-Voltage Anodizing Process 98

54. Commonly Used Metric Conversions Inch-Millimeter Conversion 99

55. Spot-Welding Parameters for Uncoated AHSS Using AC Welding Machine for IISI Group 3

    And 4 Steels 109

56. Spot-Welding Parameters for Coated AHSS Using AC Welding Machine for IISI Group 3

    And 4 Steels 109

57. Spot-Welding Parameters for Uncoated AHSS Using MFDC Welding Machine for IISI Group 3

    And 4 Steels 110

58. Spot-Welding Parameters for Coated AHSS Using MFDC Welding Machine for IISI Group 3

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And 4 Steels 110

List of Figures

Figure Page No.

1. Coring in Nickel Alloy 718 (UNS N07718) Resistance Seam Weld, 200X 23

2. Standard RWMA Nose or Tip Geometries of Spot-Welding Electrodes 31

3. ISO 5821 Female Electrode Cap Designations 32

4. Peel Test 50

5. Peel Test Specimens 51

6. Measurement of a Weld Button Resulting from the Peel Test 52

7. Fracture or Pullout Modes of Weld Buttons 52

8. Bend Test Specimen 53

9. Chisel 54

10. Tension-Shear Test Specimen 55

11. Spot Welds in Sheet 56

12. Twisting Angle  at Fracture in Tension Shear Test 56

13. Cross-Tension Test Specimens 58

14. Fixture for Cross-Tension Test (for Thicknesses up to 4.8 mm [0.19 in]) 59

15. Fixture for Cross-Tension Test (for Thicknesses 4.8 mm [0.19 in] and Over) 60

16. U-Test Specimen 61

17. U-Tension Test Jig 62

18a Pull Test (90-Degree Peel Test)—Single Weld 62

18b Pull Test (90-Degree Peel Test)–Dual Weld 63

1. Test Specimen and Typical Equipment for Torsion-Shear Test 64

2. Drop-Impact Test Specimen 66

3. Drop-Impact Test Machine 67

4. Test Fixture for Shear-Impact Loading Test 67

5. Test Fixture for Tension-Impact Loading Test 68

6. Fatigue Testing Machine 69

7. Pillow Test for Seam Welds 70

8. Typical Stack-up Configuration for Embossed Projection Welding of Sheet 71

9. Typical Configuration for Solid Projection Welding 71

10. Diagram Defining How Set-Down is Estimated on Cross-Wire Welds 80

11. Characteristics of Projection Collapse during Annular Projection Welding with Different

    Base-Projection Widths 81

12. Chart of Flash Welding Definitions 86

13. Chart of Flash Welding Definitions 87

14. Flash Welding of Tubing and Flat Sheets 90

15. Flash Welding of Solid Round, Hex, Square, and Rectangular Bars 90

16. Comparison of Tensile-Shear Strengths of Uncured and Cured (Single Spot) Weld-Bonded

    Joints of 7075-T6 Aluminum Alloy 100

17. Comparison of Fatigue Test Results of Weld-Bonded and Adhesive-Bonded Joints of

    7075-T6 Aluminum Alloy 101

18. Fatigue Test Specimen of Weld-Bonded and Adhesive-Bonded Joints 102

19. Form for Resistance Welding Data Sheet for Spot and Projection Welding 106

20. Form for Resistance Welding Data Sheet for Seam Welding 107

21. Form for Resistance Welding Data Sheet for Flash or Upset Welding 108