Crack Arrest Effect of FeMnNiSi-Inconel625-Ni60 Laminated Structure Prepared by Laser Cladding Additive Manufacturing

Area of Science:

• Materials Science and Engineering
• Additive Manufacturing
• Surface Engineering

Background:

• Laser cladding additive manufacturing faces challenges with cracking and surface crack initiation in Ni60 alloy layers on FeMnNiSi substrates.
• Dissimilar material bonding with differing thermal expansion coefficients causes interfacial stress concentration.

Purpose of the Study:

• To address cracking and surface crack initiation in Ni60 alloy cladding on FeMnNiSi.
• To develop an innovative laminate design for enhanced interfacial bonding and improved material properties.
• To investigate the microstructural mechanisms responsible for improved performance.

Main Methods:

• Fabrication of a FeMnNiSi-Inconel625-Ni60 laminate structure using laser cladding additive manufacturing.
• Analysis of interfacial microstructure, including element segregation and phase precipitation (γ″ and Laves phases).
• Mechanical testing (microhardness), wear testing, and electrochemical corrosion testing.

Main Results:

• The laminate design achieved metallurgical bonding via an Inconel625 transition layer, mitigating stress concentration.
• Synergistic Nb-Mo segregation promoted Laves phase formation, refining grain size and deflecting crack paths.
• The Ni60 cladding layer exhibited significantly enhanced microhardness (641.31 HV_0.3), superior wear resistance (73.86% lower rate), and improved corrosion resistance (71.86% slower rate) compared to the substrate.

Conclusions:

• The study demonstrates a scalable interface design strategy for heterogeneous material additive manufacturing.
• Laves phase formation is key to improving interfacial properties through microstructural regulation.
• The developed laminate structure offers significant engineering value for high-end equipment repair applications.