Electronless1Electroless nickel-phosphorous coatings are used widely 2used in many of the industrial applications because theof their unique properties, including of high such as being highly wear resistant, high and, corrosion resistant, highly along with being very hard and tough property, and tough as well as a 3good lubrication. By combining nano–sized particles as a reinforcing phase inside of the Ni-P matrix4 to obtain, alubricant. A functional nanometer composite coating with electronless co-depositionis produced by an electroless codeposition process, theco-deposition process that combinesi nano-sized particles as a reinforcing phase within a Ni-P matrix. The combined properties of the Ni-P coating are to be mainlygreatly improved and sometimessome new features are fully 5added to enhance the coating performance by adding different nanoparticles. For this purpose, differentinstance, nanoparticles likesuch as nano-SiC, WC, Al₂O₃, TiO₂, and ZnO as harder particlesincrease hardness in the coatings, and nanoparticles such as polytetrafluoroethylene (PTFE6), MoS₂, and graphite asincrease lubrication particles are added for the coatings. Out. out of. Of these nanoparticles, PTFE has gotgarnered tremendous interest bydue to its properties like a, including low such as low surface energy and7 lowerlow friction coefficient, (good for nonstick surfaces and dry lubricity, lubricants,), anti-fouling properties, and very good wear and corrosion resistantresistance. Ni-P-PTFE can be used as an anti-sticking coating. Condensedstick coatings. The condensed fluorine atomatoms in these molecules at the outer layer are the main causesource of the physical properties of PTFE like itssuch as low surface energy (18.6 mN/m) and very lower friction coefficient. By codeposition, both excellent properties for anti-stick coatings. By co-deposition of PTFE in the matrix of the coating, the properties of both Ni-P and PTFE can be used simultaneously. PTFE has excellent anti-stick properties due to the low surface energy of PTFE polymer (18.6 mN/m). Therefore another 8The potential application of a Ni-P-PTFE iscomposite to the reduction for fouling. For example, the is foreseen as a potential solution to the serious problem of the formation of deposits resembling 9limestone withon the surfaces of heat-exchange exchangers or heat-exchange elements is a serious problem. The. These sediments are one of the naturesinherent problems onin the designationdesign and operation of many types of production and processing equipmentsequipment and processes8. Unasked for These unwanted sediments can affect the equipment in two ways are:: 10

• The lower thermal conductivity of the formeddeposited sediments can increase resistance for heat transfer, and therefore reduces resistance, thereby reducing the efficiency of heat-exchanging exchangers exchanger efficiency11.
• Fouling the ducts reduces the cross-sectionsectional area of the fluid path and the friction becomes higher, causing to an increase ofincreased friction and a pressure drop increase across the system.

Any methodsMethods for reducing sediments such sedimentary build-up 12can decrease costscost. It wasWe found that the adhesion of the formedsuch sediments on the surfaces with low surface energy is poor. For this purposeTherefore, many polymeric coatings have been used. The lowerLower thermal conductivity, low and wear resistance andas well as poor adhesion ofto the substrate of the conventional polymer coatings have limited their industrial applications. Since Ni-P-PTFE coating is based on a metallic based composite, its thermal conductivity, mechanical strength, and wear-resistant properties are much biggerbetter than PTFE coatings, whileand it also has a low friction coefficient and lessas well as low surface energy.