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Most of the alloys used as bonding matrix in diamond tools show a high content of cobalt -which is undesirable due to a series of reasons. In the last decade, some attempts were made towards the reduction of the Co content in these alloys. NEXT100J alloy (50wt%Cu-25wt%Fe-25wt%Co) by Eurotungstene is an example of it.This study aims to characterize the structure, microstructure and some mechanical properties of the NEXT100 -this is an comercial alloy widely used as bonding matrix for diamonds in cutting tools, and the informations about its properties are very scarce in the literature.The NEXT100 powder was hot pressed in a graphite matrix at 35MPa/800 C/3 minutes. It was performed structural and microstructural analyses by x-ray diffraction and scanning electon microscopy, respectivelly. Wear resistance and hardness HRB tests were carried out -these are the most important mechanical tests for a diamond bonding matrix. It was demonstrated that the samples presented good mechanical properties, XRD analysis showed the presence of two phases, Cu (CFC) and the solid solution a-Fe (CCC). Microstructural aspects are high densification, homogeneous distribution of phases, and little presence of pores.

In search of the reuse of waste from civil construction, studies are presented as an alternative on the insertion of this waste into materials so that they become ecologically viable and at a lower cost. In this scope, there is the red ceramic waste (RCW), which is largely produced both in renovation works and in the stage of transporting construction components such as bricks, slabs, and floors. On the other hand, the use of cement is of great proportions, which raises concerns about the excessive consumption of non-renewable natural resources, especially in large-scale projects. Thus, the study aimed to evaluate the mechanical properties of compressive strength of concrete with partial replacement of cement by RCW and to verify the influence at different breakage ages (7, 14, 21, and 28 days). Five mixes were used, the first with 100% cement, and the others with crushed RCW to replace 5%, 10%, 15%, and 20% of the cement, and the resistance obtained according to percentages and ages was also verified of RCW through the uniaxial compression test. Thus, it was observed that for replacements of up to 15%, the strength losses were not significant, suggesting the feasibility of its use in works with high concrete demands, such as in dams.

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