Research On Tribological Property Of Ferrous Coating Sprayed On Aluminum Engine Eylinder Block

Based on the wear resistance of the body of aluminum alloy engine problems, adoptedin the engine cylinder wall coating of iron base coating solution. Overview of thedevelopment of thermal spraying coating technology preparation of cylinder, the principle,characteristics and application of arc spraying technology, and the effect of sprayingparameters on the coating performance.This article uses the electric arc spraying technology was prepared three iron basecoating:08Mn2Si,4Cr13,65Mn.By metallographic microscope and scanning electronmicroscope (SEM) analysis of characteristics of the coating. The three kinds of coatingmaterial has typical characteristics of layered coating structure, oxides and pore wrapped inflat particle boundary shows zonal distribution, also have a small amount of poredistribution inside the particle. Using SEM photos and ImageJ software to calculate thecoating porosity respectively:6.12%,3.33%,5.43%.Three mostly pore equal and unequalpore such as coating, slit pore at least. Distribution and pore space in a star-shapedtopology. Coating porosity for liquid permeability is good, through the simulationexperiments prove that the coating in the condition of lubrication conditions of wear andtear, infiltration of remaining oil. Through qualitative analysis, X-ray diffraction analyzerfor oxide found there can have the effect of grinding coated FeO oxide. Coating microhardness are:231.2HV,328.9HV,328.9HV.Using the MMU-5G universal friction andwear testing machine respectively in fluid lubrication, boundary lubrication, and dryfriction condition, tested the friction coefficient of coating material, coating wear resistanceand wear are analyzed. And compared with grey cast iron cylinder liner material made. Theselection of thermal spraying coating material preparation of cylinder to provide thereference. The experimental results showed that: in all wear test, coating wear forms aremainly abrasive wear. Under the condition of dry grinding, gray cast iron sample of minimum friction coefficient, the graphite have the effect of lubrication, and the porosity inthe iron base coating cannot give play to the role of the antifriction, lead to the frictioncoefficient is higher than the gray cast iron. Under the condition of50N load oiled,4Cr13friction coefficient and wear resistance coating is best, pore have played an important rolein oil storage antifriction, friction performance of three kinds of coating were better thanthat of the gray cast iron. Under the condition of200N load oiled,4Cr13coatingcoefficient of friction and abrasion resistance is better than that of grey cast iron and stillthe best in three kinds of coating, the friction coefficient of08Mn2Si coating than50Nload oiled condition to reduce the sharpest, explaining friction performance of the coatingto wear resistance from itself and its various antifriction structure comprehensive measure.