Foreword
With the continuous improvement in, the output power, beam quality, and energy
efficiency, high power lasers as light and heat sources of high-energy density beams
have been widely applied to material processing, forming a significant part of special
or non-traditional material processing technologies. The laser materials processing
technology has various advantages, including non-contact, precise energy control,
wide material suitability, greater flexibility, high quality, and environmental friendliness. For this reason, this technology can be used not only for efficient automatic
mass production, but also for a large variety of small batch processing, and further,
for customized production. Thus, laser processing has become an essential technology for the manufacturing industry to transform and upgrade. After years of
R&D, laser processing technology has become one of the most important technical
means of high-energy beam processing in five major manufacturing fields: welding,
cutting/drilling/marking, surface engineering, micro/nano fabrication and additive
manufacturing (3D printing).
Laser welding is a process to join similar and dissimilar materials by fusion. It has
many advantages over traditional arc welding, including higher speed, higher energy
density and depth-to-width ratio of weld joints, smaller heat-affected zones and
deformation, better quality and performance of the joints, more efficient production,
and more flexible control and operation, which shows enormous potential as an
advanced welding technology. Nevertheless, given the high energy density of laser
beam, the dynamic state of melt pool at very high welding speeds is more complex.
Welding defects elimination, welding process stability and deformation control have
become key technological challenges that need to be understood. To establish a
fundamental theory of laser welding, particularly the keyhole welding, understanding
of laser weld pool dynamics is essential.
Professor Shuili Gong and his research team have long been engaging in laser
welding basics and engineering application research. They have systematically
carried out in-depth research on interaction mechanisms between lasers and materials, weld pool behavior and its influence on welding processes, having established
a series of theories to aid the development of laser welding technologies and applications. This book is an extract and summary of achievements made by the author’s
team through many years of research, and is a collection of theoretical findings on
v
With the continuous improvement in, the output power, beam quality, and energy
efficiency, high power lasers as light and heat sources of high-energy density beams
have been widely applied to material processing, forming a significant part of special
or non-traditional material processing technologies. The laser materials processing
technology has various advantages, including non-contact, precise energy control,
wide material suitability, greater flexibility, high quality, and environmental friendliness. For this reason, this technology can be used not only for efficient automatic
mass production, but also for a large variety of small batch processing, and further,
for customized production. Thus, laser processing has become an essential technology for the manufacturing industry to transform and upgrade. After years of
R&D, laser processing technology has become one of the most important technical
means of high-energy beam processing in five major manufacturing fields: welding,
cutting/drilling/marking, surface engineering, micro/nano fabrication and additive
manufacturing (3D printing).
Laser welding is a process to join similar and dissimilar materials by fusion. It has
many advantages over traditional arc welding, including higher speed, higher energy
density and depth-to-width ratio of weld joints, smaller heat-affected zones and
deformation, better quality and performance of the joints, more efficient production,
and more flexible control and operation, which shows enormous potential as an
advanced welding technology. Nevertheless, given the high energy density of laser
beam, the dynamic state of melt pool at very high welding speeds is more complex.
Welding defects elimination, welding process stability and deformation control have
become key technological challenges that need to be understood. To establish a
fundamental theory of laser welding, particularly the keyhole welding, understanding
of laser weld pool dynamics is essential.
Professor Shuili Gong and his research team have long been engaging in laser
welding basics and engineering application research. They have systematically
carried out in-depth research on interaction mechanisms between lasers and materials, weld pool behavior and its influence on welding processes, having established
a series of theories to aid the development of laser welding technologies and applications. This book is an extract and summary of achievements made by the author’s
team through many years of research, and is a collection of theoretical findings on
v