Aluminum alloy stamping lubricating PVB coating containing MoS₂ and PTFE as composite additives

Organic coatings containing solid lubricants effectively prevent contact between recycled aluminum alloy surfaces and molds, thereby preventing damage caused by impurities. PVB-based easily removable coatings show promise in the stamping industry, but there is scarce research on the interactions of various lubricating additives within easily removable binder systems and their lubrication effects. This paper primarily concentrates on the synthesis of PVB-based composite coatings containing PTFE and MoS₂. It delves into the synergistic lubrication mechanism of MoS₂ and PTFE on mold steel, as investigated through cupping and tribological tests. The results show that the compounded coating exhibits superior dispersion, lubrication performance, tribological properties, and can withstand higher stamping loads compared to single-component coatings. MoS₂ demonstrates exceptional extreme pressure performance and enhances the transfer capability of the coating. PTFE reduces the friction coefficient while minimizing coating adhesion to the die surface. This study provides a theoretical foundation for selecting solid lubricants in organic thin coatings for stamping lubrication.