Tribological and Lubrication Performances of Nano-WO₃ and CaWO₄ Contained in Water-Based Fluid for Steel Strip during Hot Forming

Abstract

CaWO₄ and WO₃ nanoparticles were prepared by the sol-gel method and Pechini method. The morphology and structure of nano-CaWO₄ and nano-WO₃ were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Tribological, hot forming, and hot rolling lubrication properties of nano-CaWO₄, nano-WO₃, and mixed nano-CaWO₄-WO₃ as antiwear additives in water-based fluid were investigated using a four-ball friction and wear testing machine, Gleeble tester, and two-high rolling mill, respectively. Results showed that 0.3 wt% mixed nano-CaWO₄-WO₃ has excellent tribological properties in water-based fluid. The average wear scar diameter values decreased from 0.62 to 0.37 mm (mixed WO₃-CaWO₄) and the coefficient of friction value reduced from 0.080 to 0.064. This was due to the formation of a tribofilm (∼30 nm) on the worn surface during the forming process, avoiding direct contact between the metals. During Gleeble hot forming, the lubrication effect of the mixed nano-CaWO₄-WO₃ was the best. The nano-WO₃-CaWO₄ particles were relatively dispersed and dis not bond together under high temperature and pressure conditions, which played a role in reducing friction resistance between friction pairs. With the addition of 0.3 wt% mixed WO₃-CaWO₄ nanofluid, the surface quality was improved and it had the lowest surface roughness in the hot rolling process.

Keywords:

• Mixed nano-CaWO₄-WO₃
• characterization
• tribological properties
• rolling lubrication

Additional information

Funding

This study was funded by National Natural Science Foundation of China (No. 51804166), Natural Science Foundation of Jiangsu Province (No. BK20181026), Project funded by the China Postdoctoral Science Foundation (No. 2019M661461), and Opening Project of Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Foundation (No. ASMA201907). Morever, thanks for the supported by Jinling University of Science and Technology, Grant/Award Number: jit-b-201824; Jinling Institute of Science and Technology Incentive Fund, Grant/Award Number: (Jit-fhxm-201921).