Microstructure and abrasion resistance of Fe-based and Co-based coatings of AISI H13

Fe-based and Co-based cladding coatings were prepared on the surface AISI H13 hot die steel by laser cladding technology. The microstructure, hardness and abrasion resistance of two kinds of the cladding coatings were compared and analyzed by an optical microscope, a scanning electron microscope, a rockwell hardness tester and a high temperature friction and wear tester. The cladding coatings were heated to 600 °C for 1 h and repeated 4 times by a muffle furnace. The red hardness was measured. The results showed that the hardness values of the substrate, the Fe-based and the Co-based coatings were HRC 47, HRC 52 and HRC 48, respectively. The red hardness values of the substrate and the Fe-based cladding coating decreased, while that of the Co-based coating increased. The wear loss weight and the coefficient of friction of the Co-based cladding coating were the minimum. The wear mechanisms of the substrate, the Fe-based and the Co-based coatings were mainly abrasive wear, adhesion wear and mixed modes, respectively.