Optimum multilayer TiN-TiCN coatings for wear resistance and actual application

This work employed the PVD process to deposit coatings of single layer TiN, binary layer TiN/TiCN, multilayer TiN\Ti\TiN and sequenced TiN\TiCN\TiN mu ltilayer coatings with variable individual TiN and TiCN layers' thickness o n tungsten carbide disks and inserts. Also investigated herein were the fra cture mechanisms and the influence of sequence and thickness of these coati ngs on cylinder-on-disk line contact wear mode and ball-on-disk point conta ct wear mode through SRV reciprocating wear tests. Actual milling tests wer e also performed to identify the wear performance. Experimental results ind icate that the coating with a total thickness of 7 mu m and layer sequence TiN/TiCN/TiN exhibits good wear resistance on SRV wear test and milling tes t. The thickest multilayer TiN/Ti/TiN coating, although having the highest hardness, has the worst wear resistance for all tests. Notably zero-wear pe rformance was observed for all coating disks under cutting fluid lubricated condition due to the transferred layers formed between the contact interfa ce. (C) 1998 Published by Elsevier Science S.A. All rights reserved.