The hardmetal cutting tools used in machining are submitted to extreme conditions in terms of temperature and mechanical loading. A better understanding of the failure of cutting tools and capability to predict tool life are key factors in the development of new tool materials with improved mechanical behaviour. Main failure mechanisms are wear, thermal-mechanical fatigue and brittle fracture. The aim of present work is to study the mechanical behaviour of two hardmetals. The properties studied were Young's modulus, bending strength, fracture toughness and fatigue endurance. The resonant technique was used to determine elastic properties and a good agreement was found with three-point bending results.

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In the present study, the curing process of cement -bitumen treated materials (CBTM) was investigated by analysing the influence of cement dosage and curing temperature on moisture loss and evolution of complex modulus. Moreover, the study aimed to characterise the thermo-rheological behaviour of cured CBTM. Results showed that moisture loss by evaporation controls the increase in stiffness of the mixtures. However, excessive evaporation can hinder the full potential of the cement hydration process. Results also showed that the quantitative effects of curing time and loading frequency on stiffness can be superposed. Similar to hot-mix asphalt, CBTM showed a viscoelastic and thermo-dependent response. In particular, results suggested that at higher frequencies, the iso-thermal viscoelastic response is mainly affected by the aged binder whereas, at lower frequencies, the response of the mixtures depended mainly on the behaviour of the fresh binder.

The use of recycled asphalt (RA) materials in pavement rehabilitation processes is continuously increasing as recycling techniques, such as cold recycling (CR), are being utilised in increasing magnitude and greater awareness for use of recycled materials and consideration of sustainable practices is becoming common in the construction industry. The focus of this paper is on developing a state of the art and state of the practice summary of processes used for classification of RA as well as the curing and specimen preparation practices for cold-recycled asphalt mixtures. A variety of topics were explored through an exhaustive literature search, these include RA production methods, definition of RA materials, stockpiling practices, industrial operations, specimen curing and preparation practices and in-field evaluation of cold-recycled rehabilitation. This paper was developed through efforts of CR task group (TG6) of RILEM Technical Committee on Testing and Characterization of Sustainable Innovative Bituminous Materials and System