The microstructural and compositional features of the laser-solidified microstructures and phase evolutions occurring during high temperature tempering were investigated by using analytical electron microscopy with energy dispersive X-ray analysis. The cladded alloy, a powder mixture of Fe, Cr, W, Ni and C with a weight ratio of 10:5: 1:1:1, was processed with a 3 kW continuous wave CO2 laser. The cladded coating possessed the hypoeutectic microstructure of the primary dendritic γ-austenite and interdendritic eutectic consisting of (γ+M7C3). The γ-austenite is a nonequilibrium phase with extended solid solution of alloying elements. And, a great deal of fine structures, i.e., a high density ofdislocations,twins,andstackingfaultsexistedinaustenite phase. During high temperature aging,the precipitation of M23C6, MC and M2C in austenite and in situ transformation of M7C3(+γ) → M23C6 and M7C3+7→ M6C occurred. The laserclad coating revealed an evident secondary hardening and superior impact wear
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