Study On Tribological Properties Of Non Stick Ceramic Coating

With the improvement of people's living standard,the pursuit and enjoyment of dietetic culture has risen to a new height.The ceramic coating nonstick pan is easy to remove stick and to be cleaning as comparing to the traditional wok.It is also more resistant and safety as compared with PTFE coating of non-stick pan.Thus,it became the delicacy of gourmet cooking.However,the mechanical properties of ceramic coatings are poor because of its brittleness,resulting in crack and spalling of the coating in use.Moreover,non-sticking pan normally are used in acid,alkali and salt complex environment,which severely affects the service life.However,most research available nowadays are devoted to spraying method,coating thickness,adhesion,corrosion resistance and other physical properties.The tribological performance of the ceramic coating nonstick pan in different food simulants and predictions about its life have not investigated.In this paper,two kinds of ceramic coating substrate nonstick material are selected as the research object.The studies are conducted to investigate the effect of heat treatment temperature on the service life of non-sticking pan coating by simulating the daily use of the environment.We also study of tribological performance and impact wear properties of ceramic coating in the medium of acid,alkali,salt and deionized water.We hope to provide technical support to the people for reasonable use of ceramic coating of non-stick pan.Some of the experimental results are as follows:?1?At heat treatment temperature lower than 400⁰C,non-sticking coating shows good compactness,small size and small stomatal aperture.The crack forms when the temperature is higher than 400⁰C,and becomes larger with the further increase of heat treatment temperature.The coating surface becomes more rough.They are not strongly sticky to the substrate at higher heat treatment temperature.When the heat treatment temperature is lower than 300⁰C,the coating is hydrophobic,showing good non-adhesive properties.The coating becomes hydrophilic at temperature of higher than 300⁰C.The thermal treatment can improve the tribological properties of the coating.When the heat treatment temperature is between 400⁰C-600⁰C,the wear resistance of the coating is improved.But the wear resistance become worse when temperature is over 600⁰C.?2?Contact angle of non-stick coating in deionized water and aqueous solution of sodium carbonate,sodium chloride,citric acid and acetic acid is greater than 90^o whereas close to 90⁰ in ethanol solution.Thus,hydrophobic ceramic coating shows non-stick properties for most food in daily use.Compared with dry friction,the friction coefficient is small in six kinds of food simulated medium.Especially,the friction coefficient in citric acid and acetic acid was between 0.1⁰.2.?3?The impact wear properties of non-stick coating is investigated in 5 food simulating media.As comparing to that in air environment,there is no obvious hardening layer formed in food simulating media.The impact depth becomes larger,due to the erosion of the liquid.When the ceramic material is worn out,the degree of wear will be enlarged obviously.Under the influence of chloride ion,corrosion of steel is accelerated,so the impact wear degree is more obvious.