Influence of high-reactivity energetic materials on microstructure and performance on iron-based cladding layer under low laser power

Abstract

Abstract Under low laser power conditions, the cladding layer is constrained by inadequate energy density, resulting in incomplete melting of certain powder particles and the occurrence of defects such as cracks and pores within the layer. This paper utilizes a QT500 substrate and synergistically integrates high-reactivity energetic materials (H-REMs) with metal powder. By external laser energy ignition, the localized combustion of the H-REMs (Al + Fe2O3) is induced, thereby providing additional heat input during the laser cladding process. Through in-depth analysis of extensive experimental data, the influence of H-REMson microstructure and performance of alloy cladding layerhas beenrevealed. The research results demonstrate that the inclusion of H-REMs leads to a 450 K increase in the maximum temperature of the molten pool. By incorporating high-reactivity energetic materials, the energy density utilization of the composite material increased from 0.2663 to 0.7375. The combustion wave generated by H-REMs induces mixing in the molten pool, resulting in cladding layer grain refinement and an average hardness increase of 80 HV1. The friction coefficient decreases from 0.71024 (prior to the addition of H-REMs) to 0.35809, representing a reduction of approximately 49 %.