Oscillating and unidirectional sliding wear behaviour of cold sprayed Ti-6Al-4V coating on Ti-6Al-4V substrate

Abstract

Ti-6Al-4V components are widely used in the aircrafts engine or airframe parts, as landing gears or wing boxes, where the wear by unidirectional sliding or oscillating relative motion is one of the most recurrent damage processes. Recently, the deposition by Cold-Spray (CS) has been revealed as a promising alternative to repair these damaged components, increasing their useful time and decreasing the maintenance costs. Consequently, the wear resistance of the coatings could be improved by optimizing the CS processing parameters. In this work, oscillating and unidirectional sliding wear tests were planned to determine the wear resistance of Ti-6Al-4V coatings deposited onto substrates of the same Ti alloy by CS. The coatings were sprayed using two different values for two of the main spraying parameters. First, values of 800 °C and 40 bars were used for the process gas temperature and pressure, respectively, which are widely used spray conditions by researchers; and secondly, values of 1100°C and 50 bar were used for both parameters, respectively. Unidirectional sliding and oscillating wear tests were performed and the effect of the testing temperature was studied. The

Improving the oscillating wear response of cold sprayed Ti-6Al-4V coatings through a heat treatment

“…The materials studied in this investigation were CS Ti-6Al-4V coatings deposited on Ti-6Al-4V substrates with a following heat treatment. The microstructure, mechanical and tribological behaviour of the as-sprayed coating have been reported in our previous works [12], [22] and thus, the experimental procedure for the coatings deposition has already been detailed there. A gas atomized Ti-6Al-4V powder (supplied by LPW (United Kingdom)) was used for spraying.…”

“…The wear tests were conducted following the same methods and testing parameters as those reported in [12], [13]. The experiments were performed with a Wazau TRM1000 tribometer using two different tests configurations: one applying a unidirectional sliding movement and a second one with an oscillating movement.…”

“…Thus, the objective of this work has been to determine the effect of a post-heat treatment on the wear resistance of Ti-6Al-4V coatings deposited by the CS technique. This work is a further study from our previous study on the CS Ti-6Al-4V coatings wear behaviour under oscillating conditions [12].The wear resistance investigation of the same coating with a subsequent heat treatment is done here. The results of this work could provide a way to improve the behaviour of the CS Ti-6Al-4V coatings, from the tribological point of view, extending the useful life of the cold spray repaired components.…”

“…For example, Khun et al [11] deposited Ti coatings onto Ti-6Al-4V substrates by CS and they showed that the wear behaviour of the CS Ti coatings was improved compared to the bulk alloy. Additionally, to the authors knowledge, the oscillating wear in CS Ti-6Al-4V coatings has only been reported in studies conducted by the authors [12], [13]. The authors have studied the wear resistance of Ti-6Al-4V coatings deposited by CS on substrates of the similar Ti alloy [12].…”

“…Additionally, to the authors knowledge, the oscillating wear in CS Ti-6Al-4V coatings has only been reported in studies conducted by the authors [12], [13]. The authors have studied the wear resistance of Ti-6Al-4V coatings deposited by CS on substrates of the similar Ti alloy [12]. Two different spraying temperatures were selected: 800 °C and 1100 °C.…”