| JI Shao-shan,LIU Fan,FU Ge-yan,SHI Shi-hong.New Forming Method of Coaxial Wire Feeding inside Three Beams Laser Cladding[J],48(4):285-293 |
| New Forming Method of Coaxial Wire Feeding inside Three Beams Laser Cladding |
| Received:August 26, 2018 Revised:April 20, 2019 |
| View Full Text View/Add Comment Download reader |
| DOI：10.16490/j.cnki.issn.1001-3660.2019.04.040 |
| KeyWord:laser cladding three beams wire feeding inside beams light tracing spot energy deposition test |
| Author | Institution |
| JI Shao-shan |
School of Mechanical and Electrical Engineering, Soochow University, Suzhou , China |
| LIU Fan |
School of Mechanical and Electrical Engineering, Soochow University, Suzhou , China |
| FU Ge-yan |
School of Mechanical and Electrical Engineering, Soochow University, Suzhou , China |
| SHI Shi-hong |
School of Mechanical and Electrical Engineering, Soochow University, Suzhou , China |
|
| Hits: |
| Download times: |
| Abstract: |
| The work aims to study new laser cladding forming method of "coaxial wire feeding inside three beams of light" and unidirectional and multi-direction single-pass cladding forming effect. The light tracing method was used to analyze the geometrical characteristics of the spot and the energy distribution of the spot was analyzed by TracePro. The experiments of uni-directional and multi-direction single-pass cladding were carried out by device of wire feeding inside three beams to analyze the surface quality and microstructure and hardness of single pass cladding layer. The new method of "three beams coaxial wire feeding" laser cladding could shape the original circular laser beam into three fan-shaped faculae with uniform circumferential distribution. The flux of the three faculae distributed in a "cusp" shape along the z-axis direction. The wire could be evenly wrapped by three faculae. The substrate and wire were made of stainless steel 304, wire diameter was 0.8 mm, and the process parameters were as follows: negative defocus 2.5 mm, laser power 1500 W, scanning speed 3.5 mm/s, wire feeding speed 20.5 mm/s, to make unidirectional and multi-directional single-pass cladding forming test. The wire was fully melted and the cladding layer was even and smooth. The morphology and quality of the cladding layer were not affected by the scanning direction, the cladding layer and substrate were well bonded, the whole microstructure was fine, and there were no defects such as porosity and crack. The grain morphology from the bottom to the top of the cladding layer was mainly dendrite, columnar crystal, cellular crystal and dendrite. The microstructure of the cladding layer was ferrite δ and austenite γ, and the solidification mode was FA model. The main forms of ferrite δ from the bottom to the top of the cladding layer were lamellar ferrite, vermicular ferrite, skeleton ferrite and lamellar ferrite. The average hardness 228HV of the cladding layer was obviously higher than that of the substrate. The hardness transition from the bottom to the top of the cladding layer was stable, there was no obvious softening zone, the whole microstructure was fine and compact, and the grain distribution was uniform. New method of "coaxial wire feeding inside three beams of light" laser cladding can achieve accurate coupling of light and wire and substrate and wire are made of stainless steel 304, and select reasonable process parameters to obtain unidirectional and multi-direction single-pass cladding forming effects. |
| Close |
|
|
|