阿拉尔耕地沙土与65Mn摩擦行为的研究OA北大核心CSTPCD

The friction behavior between soil and metal widely exists in the work of the soil contact component of agricultural machinery,and the wear of the share parts of the high-speed plow is especially serious in the sandy soil.Because the composition of the soil is complicated,the material and processing technology of plow parts are different,and the working conditions change from time to time in actual farming,the friction behavior between sand and plow parts is very complicated.The work aims to explore the friction behavior of cultivated sand and 65Mn in Alaer,so as to provide a theoretical basis for structural design,optimization and material selection of high-speed plow.Friction and wear testing machine was used in this study.Soil water content(6％,10％,14％,18％,22％),mean particle size(0.1,0.2,0.3,0.4 mm),load(50,100,150,200,250 N),rotational speed(30,60,90,120,150 r/min)and friction duration(10,20,30,40,50 min)were selected to study the friction behavior of sand to 65Mn by single-factor multi-level tests,and the metal wear morphology was analyzed under each factor level. The results showed that with the increase of soil water content,the soil adhesion and lubricating water film increased,the friction coefficient showed an overall downward trend,and the wear amount showed a second-order parabola law.With the increase of average particle size,large-scale abrasive played the role of bearing load,the microscopic contact area decreased,and the friction coefficient and wear amount were negatively correlated.With the increase of load,the micro-cutting or abrasive breaking of the contact surface increased,the friction coefficient increased slightly,and the wear amount increased significantly.With the increase of rotational speed,the friction heat change caused by the speed did not cause the annealing and tempering effect of the metal,and the change of friction coefficient and wear amount was moderate.With the increase of friction time,the friction coefficient and wear amount increased due to the accumulation of heat,and the distribution of water between soils was uneven due to friction heat,so the friction between soil and metal gradually evolved into the friction between soils. At the same time,the wear morphology analysis found that the wear surface of 65Mn metal was always accompanied by furrow,fatigue and spalling caused by abrasive wear.After a long period of friction,it was found that the salt carried in the soil caused corrosion on the metal,the metal surface cracked,and the metal was corroded into metal salt crystals.Abrasive wear and corrosion wear interacted and aggravated the wear of 65Mn. In addition,the friction coefficient and wear amount under each factor level were analyzed by single-factor ANOVA.Compared with soil water content,load and rotational speed,the average particle size and friction time had greater effect on the friction coefficient between sand and 65Mn.The average particle size had the greatest effect on the wear of 65Mn.