Path Actuators for Magnetic Pulse Assisted Forming and Punch-less Electro-Magnetic Shearing

105 Pages·2008·3.33 MB·English

by  Scott Michael Golowin

Path Actuators for Magnetic Pulse
Assisted Forming and Punch-less
Electro-Magnetic Shearing
A THESIS
Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in
the Graduate School of The Ohio State University
By
Scott Michael Golowin, B.S.
* * * * *
The Ohio State University
2008
Master’s Examination Committee:
Dr. Glenn S. Daehn, Adviser
Dr. John E. Morral ___________________________
Advisor
Graduate Program in Material
Science and Engineering
© Copyright By
Scott Michael Golowin
2008
ABSTRACT

Path actuators can be fabricated very quickly and inexpensive, allowing
customized products to be brought to market very quickly. Only one sided tooling is
required, since an electro-magnetic force is used to drive the work sheet. This eliminates
high tolerance problems in matched tooling and could be implemented into a
manufacturing process. The path actuators were successfully used in net shape
calibration forming of doubly bent U channels and three shearing operations.
The path actuator used for calibration forming can be tuned to the requirements of
the incoming material and form, by simply varying the discharge energy through the
actuator. For both thicknesses of DP 600 (0.035 and 0.057 inches), the doubly bent U
channels were formed to 89-90° sidewall angles using 5.6 kilojoules of discharge energy.
The path actuator used in a shearing operation required tuning of two variables: offset
distance and energy. The coils were designed to create a magnetic pressure on both sides
of a shearing edge. Zero offset distance showed the most promise, shearing at the lowest
energy. It also showed promise in more complex shapes, without high tolerance issues.
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The high velocity punch-less shearing method developed here minimizes burrs on
shearing and no slivers have been seen on any of the parts sheared.
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DEDICATION
This is to my Mother, Father, and Sister. They always knew what I was capable of doing
and were always a positive encouragement. Without them I would not have made it this
far.

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ACKNOWLEDGMENTS

This is a relatively long list. First and foremost I need to acknowledge my advisor
Professor Glenn Daehn, whom gave me a chance to work in this wonderful field of
Electro-Magnetic Forming (EMF). Without him, I would not have found this exciting
work environment of explosions and high speed forming, which brings excitement to my
work every day. The next people I would like to thank is my fantastic graduate group I
have worked with: Manish Kamal, Mala Seth, Jianhui Shang, Yuan Zhang, Kristen
Banik, Jacob Portier, Jonathan Evarts, Kinga Uniocic, Geoffrey Taber, Anupam Vivek,
and last but not least Kathy Babusci. These people made work enjoyable and functional.
I would also like to acknowledge everyone that I have come in contact with throughout
various companies researching EMF.

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VITA

August 30, 1983 .......................................Born – Columbus, Ohio
2006..........................................................B.S. Material Science and Engineering, The
Ohio State University
2006 – Present ..........................................Graduate Researching Associate, The Ohio
State University
PUBLICATIONS
Research Publications
1. Scott Golowin, M. Kamal, J. Shang, J. Portier, A. Din, G.S. Daehn, J.R. Bradley,
K.E. Newman and S. Hatkevich, Application of a Uniform Pressure Actuator for
Electromagnetic Processing of Sheet Metal. J. of Mat. Eng. & Perf. 2007. 16(4): p. 455-
460
FIELD OF STUDY
Major Field: Material Science and Engineering
Area of Emphasis: Electromagnetic Forming
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TABLE OF CONTENTS

ABSTRACT ................................................................................................................ ii
DEDICATION ............................................................................................................ iv
ACKNOWLEDGMENTS ........................................................................................... v
VITA ........................................................................................................................... vi
TABLE OF CONTENTS .......................................................................................... vii
LIST OF FIGURES ..................................................................................................... x
LIST OF TABLES ................................................................................................... xvii
CHAPTER 1 ................................................................................................................ 1
INTRODUCTION ................................................................................................ 1
1.1. ELECTRO-MAGNETIC FORMING BASICS ..................................... 1
1.2. MOTIVATION FOR RESEARCH ........................................................ 5
1.3. OBJECTIVES ........................................................................................ 9
CHAPTER 2 .............................................................................................................. 10
PATH ACTUATORS ......................................................................................... 10
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CHAPTER 3 .............................................................................................................. 13
MAGNETIC PULSE ASSISTED FORMING ................................................... 13
3.1. INTRODUCTION ................................................................................ 14
3.2. EXPERIMENTAL METHOD ............................................................. 17
3.3. ANALYTICAL PROCEDURES ......................................................... 21
3.4. EXPERIMENTAL RESULTS ............................................................. 22
3.5. ANALYTICAL RESULTS .................................................................. 25
3.6. DISCUSSION ...................................................................................... 29
CHAPTER 4 .............................................................................................................. 31
PUNCH-LESS ELECTRO-MAGNETIC FORMING ....................................... 31
4.1. INTRODUCTION ................................................................................ 31
4.1.1. OTHER SHEARING METHODS ............................................. 32
4.1.2. HIGH VELOCITY SHEARING ............................................... 33
4.2. EXPERIMENTAL PROCEDURES .................................................... 40
4.2.1. TWO BY TWO PROCEDURES ............................................... 40
4.2.2. ONE BY ONE PROCEDURE ................................................... 42
4.2.3. OHIO SHEARING PROCEDURE ............................................ 43
4.3. ANALYTICAL PROCEDURES ......................................................... 45
4.4. EXPERIMENTAL RESULTS ............................................................. 47
4.4.1. TWO BY TWO SHEARING RESULTS .................................. 47
4.1.2. ONE BY ONE SHEARING RESULTS .................................... 55
4.1.3. OHIO SHEARING RESULTS .................................................. 57
4.5. ANALYTICAL RESULTS .................................................................. 64
4.6. DISCUSSION ...................................................................................... 68
CHAPTER 5 .............................................................................................................. 74
CONCLUSIONS ................................................................................................ 74
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LIST OF REFERENCES .......................................................................................... 77
APPENDIX A. ........................................................................................................... 79
TWO BY TWO SHEARING DESIGN ............................................................. 79
APPENDIX B. ........................................................................................................... 82
ONE BY ONE SHEARING DESIGN ............................................................... 82
APPENDIX C. ........................................................................................................... 86
OHIO CROSS-SECTIONAL SHEARING DATA ............................................ 86

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