Fracture behaviour of nc-TiAlN/a-Si3N4 nanocomposite coatings under cyclic nano impact testing. (2nd July 2020)

• Record Type: Journal Article
• Authors: Suresh Babu, P.; Venkatesh, L.; Srinivasa Rao, D.; Ravi, N.
• Is Part Of: Surface engineering. Volume 36:Number 7(2020)
• Page Start: 671
• Page End: 679
• Publication Date: 2020-07-02
• Subjects: nc-TiAlN/a-Si3N4 -- nanocomposite coating -- fracture -- PVD -- nanoimpact -- milling; Surfaces (Technology) -- Periodicals; Coatings -- Periodicals; 620.4405
• DOI: 10.1080/02670844.2019.1688011
• Languages: English
• ISSNs: 0267-0844

Abstract

ABSTRACT: TiN, nanocomposite nc-TiAlN/a-Si3 N4 (NC) and multi-layered TiN/NC coatings were deposited on commercially used tungsten carbide-cobalt (WC-Co) based tool material substrates by cathodic arc physical vapour deposition (CA-PVD) technique. The coatings were subjected to cyclic nanoimpact testing with impact loads of 1 and 5 mN. Properties such as fracture probability, ( h 1 – h s )/( h f – h 1 ) index and crack morphologies were analysed based on which, the performance order of the coatings was evaluated. It was observed that the multi-layer coating performed better followed by monolithic titanium nitride and nanocomposite coating (TiN/NC > TiN > NC). The order of the coatings so obtained was further compared with their relative performance during real-time machining studies. It was observed during machining that the order was changed to TiN/NC > NC > TiN. The better performance in TiN/NC coating was due to arresting of cracks formed in NC layer by TiN layer.