AWS C1.1M/C1.1:2012

An American National Standard

Recommended Practices for Resistance Welding

AWS C1.1M/C1.1:2012

An American National Standard

Approved by the American National Standards Institute

February 17, 2012

Recommended Practices for Resistance Welding

5th Edition

Supersedes AWS C1.1M/C1.1:2000

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 resis- tance 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.

International Standard Book Number: 978-0-87171-803-7

American Welding Society 550 N.W. LeJeune Road, Miami, FL 33126

© 2012 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.

Authorization to photocopy items for internal, personal, or educational classroom use only or the internal, personal, or educational classroom use only of specific clients is granted by the American Welding Society provided that the appro- priate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, tel: (978) 750-8400; Internet: <www.copyright.com>.

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 stan- dard 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 the AWS administers the process and establishes rules to promote fairness in the development of consensus, it does not independently test, evalu- ate, 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 spe- cial, 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 published 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 the issuance of new editions. This standard may also be corrected through publica- tion of amendments or errata. It may also be supplemented by publication of addenda. Information on the latest editions of AWS standards including amendments, errata, and addenda are 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.

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

On occasion, text, tables, or figures are printed incorrectly, constituting errata. Such errata, when discovered, are posted on the AWS web page (www.aws.org).

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, Technical Services Division, 550 N.W. LeJeune Road, Miami, FL 33126 (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 addition, 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 required 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, 550 N.W. LeJeune Road, Miami, FL 33126.

This page is intentionally blank.

Personnel

AWS C1 Committee on Resistance Welding

N.S. Scotchmer, Chair Huys Industries Limited

W.F. Qualls, Vice Chair Consultant

E.H. Abrams, Secretary American Welding Society

C. E. Albright The Ohio State University, Retired

T.W. Alexander Centerline (Windsor) Ltd.

B. J. Bastian Benmar Associates

J. C. Bohr General Motors

W. H. Brafford Tuffaloy Products

R. K. Cohen WeldComputer Corporation

C. S. Davidson Allweld Technologies

K. Hofman Roman Engineering Services

Advisors to the AWS C1 Committee on Resistance Welding

M. Hebert General Motors- Retired

W. Jaxa-Rozen Bombardier Transportation

B. Kelly Kelly Welding Solutions

M. Kimchi Edison Welding Institute

M. Tumuluru U.S. Steel

Special Contributor

M. Cubert Sciaky, Incorporated

This page is intentionally blank.

Foreword

This foreword is not part of AWS C1.1M/C1.1:2012, Recommended Practices for Resistance Welding, 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 addition, 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/C1.1:2000, Recommended Practices for Resistance Welding. Practices for new materi- als 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 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.

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, 550 N.W. LeJeune Road, Miami, FL 33126.

This page is intentionally blank.

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 24

   6. Titanium and Titanium Alloys 24

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

   8. Weld Discrepancies and Causes 46

   9. Weld Quality and Mechanical Property Tests 49

5. Projection Welding 69

   1. Introduction 69

   2. Embossed Projection Welding 71

   3. Solid Projection Welding 77

   4. Multiple Projection Welding 79

   5. Weld Quality and Mechanical Property Tests 79

6. Flash Welding 79

   1. Introduction 79

   2. Equipment 80

   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

   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

10. Safety and Health 105

    1. General 105

    2. Selection of Equipment 105

    3. Operator Training 105

    4. Personal Protective Equipment 105

    5. Installation 106

    6. Guarding 106

    7. Electrical 107

    8. Static Safety Devices 108

    9. Ventilation 108

    10. Maintenance 108

    11. Fire Hazards 108

    12. Noise 108

    13. Lighting 109

    14. Signs 109

    15. Hazardous Materials 109

Annex A (Informative)—Informative References 113

Annex B (Informative)—Guidelines for the Preparation of Technical Inquiries 115

List of AWS Documents for Resistance Welding 117

List of Tables

Table Page No.

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

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

3. Seam Welding Parameters for Bare, Galvanneal, and Galvanized Low-Carbon Steel 7

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

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

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

   (>700 MPa Ultimate Tensile Strength) [>101 ksi] 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) 23

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

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

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

32. Spot-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 72

38. Process Requirements for Projection Welding a Range of Heavy-Gauge Steels 73

39. Punch Design Data for Low-Carbon Steel Projections 74

40. Die Button Design Data for Low-Carbon Steel Projections 75

41. Punch and Die Design Data for Forming Projections on Stainless Steel 76

42. Projection Welding Parameters for Low-Carbon Steel 77

43. Projection Welding Parameters for Galvanized Low-Carbon Steel 77

44. Projection Welding Parameters for Stainless Steels 78

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

    Representative Light-Gauge Steels 78

46. Projection Welding Design Data for Stainless Steels 81

47. Projections for Low-Carbon Steel 82

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

List of Figures

Figure Page No.

1. Coring in Nickel Alloy 718 (UNS N07718) Resistance Seam Weld, 200X 22

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

18. Pull Test (90-Degree Peel Test) 62

19. Test Specimen and Typical Equipment for Torsion-Shear Test 63

20. Drop-Impact Test Specimen 65

21. Drop-Impact Test Machine 66

22. Test Fixture for Shear-Impact Loading Test 66

23. Test Fixture for Tension-Impact Loading Test 67

24. Fatigue Testing Machine 68

25. Pillow Test for Seam Welds 69

26. Typical Stack-up Configuration for Embossed Projection Welding of Sheet 70

27. Typical Configuration for Solid Projection Welding 70

28. Diagram Defining How Set-Down is Estimated on Cross-Wire Welds 79

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

    Base-Projection Widths 80

30. Chart of Flash Welding Definitions 86

31. Chart of Flash Welding Definitions 87

32. Flash Welding of Tubing and Flat Sheets 90

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

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

    Joints of 7075-T6 Aluminum Alloy 100

35. Comparison of Fatigue Test Results of Weld Bonded and Adhesive Bonded Joints of

    7075-T6 Aluminum Alloy 101

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

37. Form for Resistance Welding Data Sheet for Spot and Projection Welding 110

38. Form for Resistance Welding Data Sheet for Seam Welding 111

39. Form for Resistance Welding Data Sheet for Flash or Upset Welding 112

This page is intentionally blank.

Recommended Practices for Resistance Welding

1. General Requirements

   1. Scope. It is the intent of this publication to present current concepts and practices for resistance welding (and related processes) of ferrous and nonferrous metals including coated and dissimilar metals. Where practical, welding schedules are included. In other instances where schedules are too varied or the state-of-the-art is not sufficiently developed, descriptive guidelines are included to enable the user to establish welding procedures to meet its requirements.

      It is important to recognize that these recommended practices are not the only means to weld the materials and thickness shown. When developing a welding schedule(s) for a particular application, the workpiece geometry, equipment employed, and production requirements will all influence the parameters and effectiveness of the process.

      In using the data shown in the tables, it is imperative that reference be made to the appropriate text. Failure to refer to the text may result in misinterpretation of the data in the tables. The text has been kept as brief as possible and all extraneous comments have been omitted.

      For more detailed information on the fundamentals of the resistance welding processes and the types of equipment uti- lized for the different processes, consult the current AWS Welding Handbook.

   2. Units of Measurement. This standard makes use of both the International System of Units (SI) and U.S. Customary Units. The latter are shown within brackets [ ] or in appropriate columns in tables and figures. The measurements may not be exact equivalents; therefore, each system shall be used independently.

   3. Safety. Safety issues and concerns are addressed in this standard, although health issues and concerns are beyond the scope of this standard. Safety and health information is available from the following sources:

      American Welding Society:

      1. ANSI Z49.1, Safety in Welding, Cutting, and Allied Processes

      2. AWS Safety and Health Fact Sheets

      3. Other safety and health information on the AWS website Material or Equipment Manufacturers:

1. Material Safety Data Sheets supplied by materials manufacturers

2. Operating Manuals supplied by equipment manufacturers Applicable Regulatory Agencies

Work performed in accordance with this standard may involve the use of materials that have been deemed hazardous, and may involve operations or equipment that may cause injury or death. This standard does not purport to address all safety and health risks that may be encountered. The user of this standard should establish an appropriate safety program to address such risks as well as to meet applicable regulatory requirements. ANSI Z49.1 should be considered when devel- oping the safety program.