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WC-Co cemented carbides are composites constituted for two interpenetrating networks. In this work, it is attempted by combining massive nanoindentation, statistical analysis, and implementation of a thin film model for deconvolution of the intrinsic hardness and flow stress of the metallic phase. Plotting of the experimentally data as a function of the binder mean free path results in a Hall-Petch strengthening relationship with a slope (ky) of 0.98 MPa*m1/2. This value points out the effectiveness of WC-Co phase boundaries as strong obstacles to slip propagation; and thus, for toughening of brittle phase by means of crack-bridging ductile reinforcement. Title:Hall-Petch strengthening of the constrained metallic binder in WC-Co cemented carbides: Experimental assessment by means of massive Nanoindentation and statistical analysis.Dear Professor E. J. Lavernia, Thank you for your email of July 23 informing about your positive consideration for publication of the referred manuscript, upon completion of mandatory revisions, in Materials Science and Engineering -A. From the report appended in your email, it seems that the reviewer has read the paper carefully. Please thank him for his care and criticism. As requested, we have considered the indicated comments, and our responses (and modificationsred color text in the revised version) are as follows:Reviewer#1's comments (RC): The idea of this paper is good and the paper deserves to be published in MSEA but after the addition of the mathematical equations used in treating the data. RC1.-The introduction need to be re-polished carefully from two points: a) Conversion of long statement to short one, and b) Simplify the statements.Example: There are some long statements and it is prefer to be shortened for example, in the introduction, "Within this evolution trend, although the intrinsic….for enhancing material performance", This statement need to be shortened and to be simplified.Response: We agree with this comment and the introduction has been re-polished following the comments mentioned by the reviewer as it is presented below:WC-Co cemented carbides, usually referred to as hardmetals, are established forefront materials for tools, structural components and wear parts with stringent requirements.They exhibit an exceptional combination of strength, toughness and wear resistance as a result of the extremely different properties of their two interpenetrating constitutive phases: hard, brittle carbides and a soft, ductile metallic binder. Historically, the ever increasing implementation of hardmetals has mainly taken place on the basis of replacement of steels in machining tools. Main reasons for it are the higher hardness Abstract: WC-Co cemented carbides are composites constituted for two interpenetrating networks. In this work, it is attempted by combining massive nanoindentation, statistical analysis, and implementation of a thin film model for deconvolution of the intrinsic hardness and flow stress of the metallic phase. Plotting of the experimentally data as a fun...

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The effect of corrosion damage on cemented carbides was investigated. The study included residual strength assessment and detailed fractographic inspection of corroded specimens as well as detailed 3D FIB-FESEM tomography characterisation. Experimental results point out a strong strength decrease associated with localised corrosion damage, i.e. corrosion pits acting as stress raisers, concentrated in the binder phase. These pits exhibit a variable and partial interconnectivity, as a function of depth from the surface, and are the result of heterogeneous dissolution of the metallic phase, specifically at the corrosion front. However, as corrosion advances the ratio between pit depth and thickness of damaged layer decreases. Thus, stress concentration effect ascribed to corrosion pits gets geometrically lessened, damage becomes effectively homogenised and relatively changes in residual strength as exposure time gets longer are found to be less pronounced.

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There is a major interest in replacing cobalt binder in hardmetals (cemented carbides) aiming for materials with similar or even improved properties at a lower price. Nickel is one of the materials most commonly used as a binder alternative to cobalt in these metal-ceramic composites. However, knowledge on mechanical properties and particularly on fatigue behavior of Ni-base cemented carbides is relatively scarce. In this study, the fatigue mechanics and mechanisms of a fine grained WC-Ni grade is assessed. In doing so, fatigue crack growth (FCG) behavior and fatigue limit are This microscopic failure mode is rationalized on the basis of the comparable sizes of the cyclic plastic zone ahead of the crack tip and the characteristic microstructure length scale where fatigue degradation phenomena take place in hardmetals, i.e. the binder mean free path.