In this paper, a proof of time-dependent behavior of heat flux into a cutting tool is built. Its implementation calls for a new method for estimating heat flux, which was developed using an inverse problem technique. A special experimental setup was designed and manufactured to implement the method. A series of dry machining experiments were conducted with high speed steel and cemented carbide tooling. A two-stage procedure was developed to overcome the ill-posedness of the inverse heat conduction problem by transforming it into a well-posed parameter estimation problem. The first stage retrieves the value of the heat flux and specific tool heating energy Et. The second stage parametrizes and compares predefined heat flux behaviors. It was found that the time dependency of heat flux is best described by a decreasing power function.

The aim of this paper is to gain a better understanding of the impact different micro-geometries has on stress distribution in cutting tools. Both principal and effective stress distribution are studied. These quantities have a major impact on the occurrence of damages in the cutting tool such as crack formation, flaking, chipping, breakage and plastic deformation. The development of a stagnation zone is also investigated as well as the effect tool microgeometries have on this zone. A finite element model is developed which enables the examination of these aspects, in detail. It was found that the model predicted these metal cutting phenomena with high accuracy. Cutting forces is within the standard deviation of experimental results. The experimental results also indicate that the stress distributions and the stagnation zone have been simulated correctly. This study has shown that the micro-geometries of the cutting tool have a great potential in reducing the maximal tensile/principal stress. This research work has also shown that the size of the stagnation zone can be controlled by micro-geometries on the cutting tool, which in turn can have an effect on the wear on the cutting edge.

Performance and wear mechanisms of novel superhard diamond and boron nitride based tools in machining Al-SiCp metal matrix composite . Performance and wear mechanisms of novel superhard diamond and boron nitride based tools in machining Al-SiCp metal matrix composite. Wear,[376][377][152][153][154][155][156][157][158][159][160][161][162][163][164]. https://doi. AbstractMetal matrix composites are the desired materials in aerospace and automotive industries since they possess high specific strength. However addition of reinforcement to the matrix material brings the adverse effects of high wear rate of tool materials used in their machining. The current study addresses the issues of wear and performance of superhard tools when high speed machining cast Al-Si alloy reinforced with particulate SiC (20% vol.). A wide range of developed superhard materials was compared to the commercial PCD tools. Nano grain sized wBN-cBN, binderless cBN; B6O-cBN, nano-diamond with WC binder; diamond/MAX-phase; and diamond/SiC tool materials were employed. Tool wear tests involved dry machining at cutting speeds 200 and 400 m/min at fixed cutting length of 14 000 meters. Use of nano-diamond/WC and diamond/MAXphase composites resulted in their rapid deterioration due to primarily adhesive pluck-out of diamond and binder phase. Diamond/SiC material exhibited slightly lower performance than the PCD, with the primary wear being the abrasive on the SiC binder phase. Machining with cBN-based tooling at lower speed lead to formation of stable build-up layer, frequently accompanied by severe seizure of tool and workpiece material. However at speed of 400 m/min the absence of such build-up layer caused rapid tool wear. In case of PCD and diamond-SiC tooling build-up layer remained stable in the whole cutting speed range. Presence of chemical and diffusional wear mechanisms for this tooling has been confirmed through scanning and transmission electron microscopy. Archard-type model of abrasive tool wear was developed for modelling of tool deterioration for all studied tool materials.

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