Aqueous nanolubricants containing ZrO2 nanoparticles. graphene oxide (GO) nanosheets. or hybrid nanoparticles of ZrO2 and GO were formulated using a cost-effective ultrasonication de-agglomeration method. The friction and wear characteristics of these water-based nanolubricants were systematically investigated using a block-on-ring testing configuration with a stainless- and alloy ste... https://www.relicsbook.com/product-category/autographed-wrestling-photos/