Abstract：The fundamental principle,development state,solidification microstructure and forming characters of laser solid forming(LSF) were investigated throughly.It was found that to acquire idea forming result,the height,width and the overlap rate of the single cladding layer must be accurately controlled.The forming principle of the microstructure was also studied during laser solid forming in this paper.The microstructure of the sample was made up of thin and long epitaxial growth dendrites,the primary spacing of which is about 10~30μm. The directional solidification microstructure or even single crystal was obtained based on the rigid processing characters control.Combining the research results of the forming character,the samples with different metal were obtained by using optimized processing characters.The inner part of the sample wa dense,the surface quality was fine and was free of defect.
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