The effect of cladding speed on phase constitution and properties of AISI 431 stainless steel laser deposited coatings

Shorter processing time has given impetus to laser cladding technology and therefore in this research the AISI 431 martensitic stainless steel coatings are laser deposited at high cladding speeds, i.e. up to 117 mm/s. The analysis of phase constitution and functional properties of the coatings are performed by optical microscopy, Scanning Electron Microscopy (SEM), and hardness and sliding wear tests. The outcome of this research shows that an extreme refinement of the solidification structure will influence the phase constitution of the coatings by lowering the M-s temperature and hence stabilizing the austenite which results in lower hardness values and increased wear rates. These results confirm that the structural refinement obtained by higher cladding speeds is not helpful for improving the hardness and wear properties of laser deposited martensitic stainless steel coatings. (C) 2011 Elsevier B.V. All rights reserved.