AVS 58th Annual International Symposium and Exhibition
    Tribology Focus Topic Wednesday Sessions
       Session TR-WeA

Paper TR-WeA10
Study on the Fatigue Wear Behaviour of TiN and WC DLC-coated Stainless Steel under Inclined Impact-Sliding Load Tests

Wednesday, November 2, 2011, 5:00 pm, Room 111

Session: Emerging Interfaces of Tribological Importance
Presenter: Ying Chen, University of Windsor, Canada
Authors: Y. Chen, University of Windsor, Canada
X. Nie, University of windsor, Canada
Correspondent: Click to Email
WC/C diamond-like carbon (DLC) coatings and Titanium Nitride (TiN) coatings are widely used in industrial machinery and tools. Both of the two coatings have extremely hard surfaces comparing to the stainless steel substrate SS316L. The W: DLC coating gives low coefficients of friction against a number of counterfaces, has relatively high lubricity and resistance to adhesive wear comparing to the TiN coating. In this study, a new method which is called cycled inclined impact-sliding test is introduced and utilized to study the coating durability under a combined force of an Impact force Fi and Pressing force Fp (Fi/Fp=200N/400N and 200N/200N) and the fatigue wear behaviors after up to 1000 cycles impact tests. A 10mm steel (AISI 52100) bearing ball is used as the impact indenter. Due to the low coefficient of friction of W:DLC coating against steel counterface, greater impact cycle was endurable before the failure of the coating when impacted in dry air condition. Under inclined impact and sliding forces, fatigure cracking was first initiated, followed by chipping and pealling of the coatings. The SEM showed that different types of fatigue wear cracks were found which distributed in the different areas (head and tail parts) of the impact scars. Most of those scars, observed by 45º tilted cross-sectional SEM, penetrated the coating and caused hardening of the under layer (interface layer). Material transfer from the indenter ball could also be detected by EDX in some areas of the impact scar on both of the coating materials.