Experimental investigations of electrodeposited Zn–Ni, Zn–Co, and Ni–Cr–Co–based novel coatings on AA7075 substrate to ameliorate the mechanical, abrasion, morphological, and corrosion properties for automotive applications

Abstract The aluminum (Al) alloy AA7075 is widely used in various industries due to its high strength-to-weight ratio, which comparable and replaceable steel many applications. However, it has poor resistance wear corrosion compared other Al alloys. conventional pressure die coating with Cr cadmium led premature failure while the load applied. It indeed develop a novel method improve mechanical, wear, properties of alloy. In present investigation, binary ternary metals such as zinc–nickel (Zn–Ni), zinc–cobalt (Zn–Co), nickel–chromium–cobalt (Ni–Cr–Co) are electroplated on substrate material (AA7075). order ensure optimal adhesion, surface was pre-treated laser treatment (LST). mechanical studies have been carried out uncoated coated materials. observed from findings that higher than binary-coated material. 64% non-heat-treated status 67% heat-treated condition specimens. tensile strength (MPa) Ni–Cr–Co casting (PDC) deposits (582.24 > 566.07 Zn–Co 560.05 Zn–Ni 553.64 condition). presence crystalline structure alignment Co Ni atoms could significantly coatings AA 7075 PDC substrates when coatings. scanning electron microscopy (SEM) images, X-ray diffraction (XRD), photoelectron spectroscopy materials corroborated analyses properties. XRD analysis reported peaks γ-NiZn 3 (831), γ -Ni 2 Zn 11 (330), 631 θ values 38, 43, 73° confirming deposit substrate. pattern Zn–Co-coated revealed three strong (110), (111), CoZn (211) two feeble ε-CoZn (220) (301) clearly visible. exhibited solid solution body-centered cubic formation at lattice plane (220), (210) crystal constant 2.88 A°. SEM image for both binary- ternary-coated deposited displayed shallow pits hitting by progressive particles. illustrated smaller globular structure. morphology unveiled evenly distributed dot-like submerged particles galaxy atoms. To understand effectiveness bonding texturing, cross-section furthermore effective adhesion PDC; this also be reason enhancement microhardness, said coating.