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The aim of this work was to investigate fracture and fatigue behaviour of TiC-Ni/Fe cermets under monotonic and cyclic loading.The fracture toughness K Ic was determined by a conventional testing method (using single edge notched beam) and evaluated by an indentation technique (indentation fracture toughness (IFT)). Results from both experimental routines were analysed and compared with the reference hardmetal -WC-10 wt% Co. As the result, a novel sequence for estimation of the IFT for TiC-and WC-based cemented carbides is presented.The transverse rupture strengths R TZ and fatigue strengths σ f at a given life (10 7 cycles) were obtained by the testing of unnotched and notched specimens with the three-point bending scheme. Considering that the fatigue lifetime of cemented carbides is given by the subcritical crack growth of pre-existing defects, a linear elastic fracture mechanics approach is attempted to assess fatigue life-fatigue crack growth relationships for the studied materials.The reliability of used fatigue mechanics approach is proved by the excellent agreement observed between estimated and experimentally determined values for fracture toughness and fatigue strength of the investigated materials.

Thin hard physical vapor deposited (PVD) coatings play significant role on wear performance of fine-blanking punches in the presence of extremely high contact stresses. Nevertheless it seems that in blanking or fine-blanking the coatings are selected based on coincidence, trial-error-method or latest trends. There is limited information about planning and conducting the fine-blanking industrial field tests and measuring the wear of different coatings. In the present study a set of fine-blanking punches and laboratory specimens were prepared with three coatings-TiCN, nACRo and nACo. As substrate material Böhler S390 Microclean high speed steel was used. Coating mechanical properties (modulus of elasticity and nanohardness) were measured and wear rate with alumina ball was determined using the reciprocating sliding test. Wear of coatings was measured from punches after industrial use. All of the tested coatings showed high variance of wear. However coatings nACo and nACRo have better average wear resistance in fine-blanking compared with the well-known TiCN. Industrial field tests show correlation to the ratio elastic strain to failure H/E.