Tribological Properties and Cutting Performance of AlTiN Coatings with Various Geometric Structures

Abstract

The development of advanced machining techniques requires high-performance tool coatings. To improve the wear resistance and cutting performance of AlTiN coatings, a structure optimization strategy involving bias control and a nano-multilayer architecture strategy is presented. The investigated AlTiN coatings were deposited by cathodic arc evaporation and studied with regard to phase structure, hardness, adhesion, and tribological properties by a combination of X-ray diffraction, nanoindentation, scratch, and ball-on-disk friction tests. A high bias potential (up to −120 V) with enhanced adatom mobility suppressed the formation of the wurtzite structure AlN in AlTiN. In addition, the epitaxial growth of Al0.67Ti0.33N on Al0.5Ti0.5N in the AlTiN nano-multilayer could also promote the single-phase structure. The hardness of AlTiN-based coatings with a dominated cubic structure was 3–4 GPa higher than conventional ones. In addition, the interlayer interfaces in the Al0.67Ti0.33N/Al0.5Ti0.5N multilayer could deflect the cracks and thus improve the fracture toughness. As a consequence, the Al0.67Ti0.33N/Al0.5Ti0.5N multilayer with enhanced mechanical properties obtained the lowest wear rate of 1.1 × 10−5 mm3/N·m and the longest cutting lifetime of 25 min during dry turning the SUS304 stainless steel.

Performance analysis of twin-layer AlTiN and TiCN coated inserts during high speed turning of SS304 with synthetic coolant at 0°C

“…The surface coatings applied to the inserts are capable of withstanding high temperatures, sudden impact loads, and high strength. 10 The surface coating materials, preparation, coating process on substrate, and other details are discussed below: AlTiN-coated inserts : The substrate used for the coating is made up of tungsten carbide, consisting of 93% tungsten grain and 7% cobalt, which act as binder agents. The average grain size of the substrate powder is 1.5 µm.…”

“…The surface coatings applied to the inserts are capable of withstanding high temperatures, sudden impact loads, and high strength. 10 The surface coating materials, preparation, coating process on substrate, and other details are discussed below:…”

The Impact of a Movement Type on Tribological Properties of AlTiN Coating Deposited on HS6-5-2C Steel

“…The coating process parameters can significantly affect the properties of the tools. AlTiN coatings can be deposited using a variety of physical vapour phase PVD deposition techniques by: cathodic arc deposition [16] magnetron sputtering [16,17] and hybrid vapour deposition/arc sputtering. The cathodic arc deposition method is characterised by high ionisation rates, deposition efficiency and can be used in the industrial production of coatings for cutting tools [9].…”

Technologies of Coatings and Surface Hardening: Industrial Applications

“…The most advanced and recently developed coating and surface-hardening technologies make it possible to obtain almost the full range of physical-mechanical and crystalchemical properties of the metalworking tool surface and electronic component surface for a wide range of applications to enlarge product operational life for working under the most extreme mechanical and thermal loads [1][2][3]. The scientific attitude to improving the surface layer parameters of the product made of traditional industrial materials or new advanced composites and nanocomposites requires budget material and time investments [4,5]. It hinders the industrial introduction of innovations and slows down the progress of the transition to the technological level associated with the concept of nanoindustry [6][7][8].…”