TiAlN is a very popular coating for high-speed cutting manufacturing processes. Nevertheless, it is important to develop research work concerning the durability of this kind of coatings. Design and producing coatings based on TiAlN with interlayers of metal with low elastic modulus, like Al, Ti or Cu may contribute to improvement of cutting efficiency. Interlayers with 80 nm of thickness, in alternateness with TiAlN with different periods were sputtered. In general, the hardness and Young's modulus of the multilayer coatings had slight smaller values, but similar relations of H/E in monolithic TiAlN coatings. However, in multilayers based on Al and Cu there is an important decrease in the H 2 /E ratio. Moreover, the adhesion Lc 2 values of scratch test show an important increase, particularly in Al and Ti interlayers, which can be considered as an important contribution in the improvement of the cutting performance of TiAlN-based coatings.

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a b s t r a c tThe current trend towards miniaturization has led to the increasing use of stainless steel powders as raw material in the manufacture small parts with complex shapes, e.g. medical devices. This paper focuses on the role of coated and uncoated low carbon stainless steel powders, having d 50 = 7.3 m, normal particle size distribution and a shape factor of 1 on additive processes used in micromanufacturing, e.g. micro powder injection moulding (PIM). Surfaces were treated using a magnetron sputtering deposition apparatus equipped with a high frequency powder vibration and a continuous feed system. The results clearly show that the coated powders assume an "artichoke" morphology, which significantly increases the surface area. This combined with their nanocrystalline character leads to higher flowability than uncoated powders. However, no improvements have been observed concerning the critical powder volume concentration (CPVC) in feedstocks for PIM processing. In consolidation processes, the debinding temperatures can attain values higher than 500 • C. After debinding and sintering, the coating of steel powders can show lower carbon contamination in solid solution than uncoated ones. This result is very important particularly for powder microtechnology of low carbon stainless steel.

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