Chinese Journal of Lasers, Volume. 43, Issue 8, 802009(2016)
Microstructure Evolution of Heat-Affected Zones of 28CrMoNiV Steel Repaired by Lasers
A laser cladding test on a 28CrMoNiV substrate by a 3 kW broadband semiconductor laser is conducted, and the refabrication process is optimized with the aid of simulation of the temperature fields in the areas of heat-affected zones (HAZ). By means of optical microscope, scanning electron microscope, and X-ray diffraction, the microstructures in the HAZ and substrate zone are studied. The tensile test is conducted to investigate the tensile performance of the repaired laser cladding HAZ. The results show that, in the HAZ of the single-layer cladding sample, there exists a martensite phase transformation and an undesirable microstructure composed of martensite and δ-ferrite distributes at the top of the HAZ. The simulation results indicate that this undesirable microstructure can be eliminated if the over-three-layer cladding is adopted. The tensile testing results show that the HAZ with three-layer cladding has the average tensile strength up to 927.35 MPa, which is higher than those of the substrate or the HAZ with single-layer cladding. The average fractural elongation of the HAZ with three-layer cladding is 10.23%, which is a little higher than that of the single-cladding and much closer to that of the substrate.
Get Citation
Copy Citation Text
Li Yundong, Dong Gang, Yao Jianhua. Microstructure Evolution of Heat-Affected Zones of 28CrMoNiV Steel Repaired by Lasers[J]. Chinese Journal of Lasers, 2016, 43(8): 802009
Category: laser manufacturing
Received: Jan. 14, 2016
Accepted: --
Published Online: Aug. 10, 2016
The Author Email: Yundong Li (liyundong10@163.com)