Today's machine components have more power, so researchers have to engineer materials that can withstand high-speed dry sliding stress. Consequently, this study examined dry sliding wear in an Austempered ductile iron (ADI) with fine ausferrite microstructure and low retained austenite. In addition, a chrome steel counterbody ball with a hardness of 60 HRC was evaluated. The wear rate, coefficient of friction and wear mechanisms were investigated. Two friction and wear regimes were identified. In the first regime of wear, wear rate increases from 21.68 to 36.29 x 10-6 mm3/Nm at low pressure; however, with high pressure, it decreases from 36.29 to 17.06 x 10-6 mm3/Nm. In second regime, at higher speed range, wear rate decreased from 17.68 to 3.11 x 10-6 mm3/Nm with applied pressure range. This behaviour well explained by the strain hardening of filmy austenite, causing compressive stress development in the neighbourhood, resulting in ADI becoming tougher at higher pressures and speeds in response.
Dr. Sandan Kumar Sharma
Dr. Pavol Hvizdoš
Dr. Michael J. Reece
Dr. Salvatore Grasso E-mail addresses
|Queen Mary University of London, London, UK and Slovak Academy of Sciences, Slovakia