The sinterability and mechanical properties of different metallic alloys, used as bonds for diamond impregnated tools, have been studied as a function of the processing conditions and the composition of the powder mixtures. The bonds based on Fe-Cu and Fe-Co-Cu prealloyed powders have been consolidated up to full density by free sintering in a reducing atmosphere at temperatures ranging from 750 to 1000 °C. These new alloys present hardness values ranging from 88 to 108 HRB with yield stresses between 600 and 400 MPa and elongations up to 25 %. Calorimetry and the analysis of the sintering atmosphere have been used to understand the densification process of these alloys. Changes in mechanical properties have been related with key microstructural phenomena, i.e. grain growth, phase transformation, precipitation and solid solution strengthening.
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