viii
Preface
penetration welding as the laser output power increases, beam quality improves, and
theoretical research and technology continues. The welding technology constantly
develops. Laser butt welding, laser superposition welding, hybrid laser-arc welding,
laser welding with filler wires, dual-beam laser welding, multi-beam laser welding,
dual-beam laser welding with filler wires, ultra-narrow gap laser welding, all-position
laser welding, long-focal-length dynamic laser welding, and other technologies
emerge and develop one after another. Accordingly, welding equipment, welding
systems, and process detection and control technologies are improved, laying a solid
foundation for the application of laser welding technology in the national economy
and defense development.
Since the laser technology has been applied to welding, the theoretical research of
laser welding moves along. Systematic research has been carried out from different
modes of the interaction mechanism of lasers and materials, the weld pool behavior
and its influence on the welding process, which provides solid theoretical support for
the development and application of the laser welding technology. The scientific and
technical workers have studied the interaction mechanism of lasers and materials
and the physical state change process of materials, obtaining two typical welding
modes of laser heat conduction welding and deep penetration welding. They realized that the laser energy density is the key parameter of the mutual transformation
of the two welding modes and found that the weld pool generated in deep penetration
laser welding is characterized by the dynamic keyhole behavior, and the thermodynamic equilibrium in weld pool keyholes of deep penetration welding is a necessary
condition for the stable formation of keyholes. Through application research and
engineering practice of laser welding, welding scientific workers discovered that the
weld pool behavior in deep penetration laser welding plays an important role in the
stability of laser welding. Studying and mastering the dynamic behavior of weld
pools in laser welding becomes the key foundation for the optimization of technical
parameters and stability control in welding.
Over the years, with the support of government agencies and organizations,
Beijing Aviation Manufacturing and Engineering Institute, Huazhong University of
Science and Technology, Xi’an Jiaotong University, Harbin Institute of Technology,
Dalian University of Technology, etc., have conducted in-depth research on the technology basis of laser welding, and have carried out continuous study on the weld pool
behavior in laser welding, systematically revealing the weld pool behavior in laser
welding and its influence, providing theoretical support for the practical application
and promotion of the laser welding technology, and laying a solid foundation for
drafting this book.
This book systematically describes the main research achievements on the weld
pool behavior of domestic laser welding in recent years. It refines and summarizes the
relevant research work from the institutions such as National Defense Science and
Technology Key Laboratory of High Energy Beam Processing Technology in Beijing
Aviation Manufacturing and Engineering Institute, Huazhong University of Science
and Technology, Xi’an Jiaotong University and Taiyuan University of Science and
Technology. The research work of the authors’ research team especially provides
great support to this book.
Preface
penetration welding as the laser output power increases, beam quality improves, and
theoretical research and technology continues. The welding technology constantly
develops. Laser butt welding, laser superposition welding, hybrid laser-arc welding,
laser welding with filler wires, dual-beam laser welding, multi-beam laser welding,
dual-beam laser welding with filler wires, ultra-narrow gap laser welding, all-position
laser welding, long-focal-length dynamic laser welding, and other technologies
emerge and develop one after another. Accordingly, welding equipment, welding
systems, and process detection and control technologies are improved, laying a solid
foundation for the application of laser welding technology in the national economy
and defense development.
Since the laser technology has been applied to welding, the theoretical research of
laser welding moves along. Systematic research has been carried out from different
modes of the interaction mechanism of lasers and materials, the weld pool behavior
and its influence on the welding process, which provides solid theoretical support for
the development and application of the laser welding technology. The scientific and
technical workers have studied the interaction mechanism of lasers and materials
and the physical state change process of materials, obtaining two typical welding
modes of laser heat conduction welding and deep penetration welding. They realized that the laser energy density is the key parameter of the mutual transformation
of the two welding modes and found that the weld pool generated in deep penetration
laser welding is characterized by the dynamic keyhole behavior, and the thermodynamic equilibrium in weld pool keyholes of deep penetration welding is a necessary
condition for the stable formation of keyholes. Through application research and
engineering practice of laser welding, welding scientific workers discovered that the
weld pool behavior in deep penetration laser welding plays an important role in the
stability of laser welding. Studying and mastering the dynamic behavior of weld
pools in laser welding becomes the key foundation for the optimization of technical
parameters and stability control in welding.
Over the years, with the support of government agencies and organizations,
Beijing Aviation Manufacturing and Engineering Institute, Huazhong University of
Science and Technology, Xi’an Jiaotong University, Harbin Institute of Technology,
Dalian University of Technology, etc., have conducted in-depth research on the technology basis of laser welding, and have carried out continuous study on the weld pool
behavior in laser welding, systematically revealing the weld pool behavior in laser
welding and its influence, providing theoretical support for the practical application
and promotion of the laser welding technology, and laying a solid foundation for
drafting this book.
This book systematically describes the main research achievements on the weld
pool behavior of domestic laser welding in recent years. It refines and summarizes the
relevant research work from the institutions such as National Defense Science and
Technology Key Laboratory of High Energy Beam Processing Technology in Beijing
Aviation Manufacturing and Engineering Institute, Huazhong University of Science
and Technology, Xi’an Jiaotong University and Taiyuan University of Science and
Technology. The research work of the authors’ research team especially provides
great support to this book.