No abstract

No abstract

In this work, Fe-Al-Si alloys were prepared by reactive sintering. The contents of silicon and aluminium ranged between 0-30 wt-% and 10-40 wt-% respectively. Aluminium, silicon and AlSi30 master alloy powders prepared by mechanical machining and/or milling and commercial powder of high purity iron were used for sintering. Powders were blended and pressed at room temperature. Sintering was carried out at 950uC for 60 min. Compact low porosity products without unreacted components were prepared, if a powder mixture contained 15-20 wt-% of silicon and 20-25 wt-% of aluminium. It was shown that these materials contain two phases (Al 2 FeSi and AlFeSi). Hardness of the alloys increased with growing silicon content, while the increase in aluminium content reduced the hardness.

A variety of cutting tool materials are used for the contact mode mechanical machining of components under extreme conditions of stress, temperature and/or corrosion, including operations such as drilling, milling turning and so on. These demanding conditions impose a seriously high strain rate (an order of magnitude higher than forming), and this limits the useful life of cutting tools, especially single-point cutting tools. Tungsten carbide is the most popularly used cutting tool material, and unfortunately its main ingredients of W and Co are at high risk in terms of material supply and are listed among critical raw materials (CRMs) for EU, for which sustainable use should be addressed. This paper highlights the evolution and the trend of use of CRMs) in cutting tools for mechanical machining through a timely review. The focus of this review and its motivation was driven by the four following themes: (i) the discussion of newly emerging hybrid machining processes offering performance enhancements and longevity in terms of tool life (laser and cryogenic incorporation); (ii) the development and synthesis of new CRM substitutes to minimise the use of tungsten; (iii) the improvement of the recycling of worn tools; and (iv) the accelerated use of modelling and simulation to design long-lasting tools in the Industry-4.0 framework, circular economy and cyber secure manufacturing. It may be noted that the scope of this paper is not to represent a completely exhaustive document concerning cutting tools for mechanical processing, but to raise awareness and pave the way for innovative thinking on the use of critical materials in mechanical processing tools with the aim of developing smart, timely control strategies and mitigation measures to suppress the use of CRMs.