Development of Functionally Graded Nodular Cast Iron Reinforced with Recycled WC Particles
Résumé
The work deals with the development of a graded composite based on DIN 1693 nodular cast iron reinforced with WC particles from recycled cutting tools. A superficial composite layer with a specific profile and thickness is designed to provide high wear resistance in working surfaces in products like impact crushers for sugar industries or sinter plants. The process involves the addition of the ceramic particles to the liquid metal through a specially designed casting process using EPS pattern. Different casting conditions, contents and dimensions of reinforcing particles were tested. Obtained products were characterized concerning the dispersion of the reinforcing agent and quality of reinforcement/matrix interface. Results show the possibility of incorporating WC in the cast iron matrix with the pre-designed profile of WC distribution in the working surface of the product. During processing some disaggregation of micro carbide particles from the recycled material is observed, resulting in a finer dispersion of WC in the metallic matrix. Microstructural changes in the matrix in the composite region results in higher perlite/ferrite ratio related to the non-reinforced region of the product.