Single-Frequency Ultrasound And Micro-Particles On Ti-Ta Alloy Study On The Influence Of Cavitation Damage

Cavitation is a common phenomenon in fluid engineering machinery.Cavitation will not only affect the efficiency of mechanical work,cause noise,vibration,serious will cause surface damage of materials.In many engineering applications,the flow passage component in contact with liquid medium are subjected to cavitation corrosion.Ti-Ta alloy is an excellent biomedical metal material,but it is difficult to cut,difficult to process and low processing efficiency.At present,there are few reports on the use of cavitation erosion to micro-machining difficult-to-cut materials.This dissertation studies the influencing factors and inducing mechanism of cavitation erosion on the surface of Ti-Ta alloy,which has important engineering application significance for ultrasonic machining Ti-Ta alloy.The main research contents are as follows:1.Using an ultrasonic vibration cavitation experimental platform,the effect of ultrasonic cavitation time on the cavitation behavior of Ti-Ta alloy specimens was studied.The changes in surface morphology before and after cavitation were observed,and the changes in roughness and surface Vickers hardness were measured,which characterized the degree of cavitation damage and the important influence of experimental time on specimen surface morphology.As the cavitation time increased,the cavitation pit depth became deeper,and with increasing cavitation time,the surface roughness and Vickers hardness increased.The degree of cavitation damage increased with increasing cavitation time.Secondly,the effects of single-frequency and dual-frequency ultrasonic sources on cavitation of Ti-Ta alloy specimens in pure water were compared.Through systematic comparison,after dual-frequency cavitation,the depth of surface cavitation pits,roughness,and Vickers hardness of the test sample are all higher than those of single-frequency cavitation.Therefore,the longer the single-frequency cavitation time,the stronger the cavitation damage to the Ti-Ta alloy.The degree of cavitation damage caused by dualfrequency cavitation is significantly higher than that of single-frequency cavitation.2.Ultrasound cavitation experiments were conducted by adding micro-particles to liquid media to analyze the effects of micro-particle concentration,particle size,and material on cavitation of Ti-Ta alloy specimens.The number and morphology of cavitation pits on the test sample surface were observed,and the depth and roughness of the cavitation pits were measured.The study showed that the extent of cavitation damage on the surface of the Ti-Ta alloy specimen increased with an increase in the suspension concentration;as the particle size increased,the degree of cavitation damage decreased continuously,and the depth of the cavitation pit increased with an increase in the micro-particle size.The addition of different micro-particles worsened the degree of surface cavitation damage to the Ti-Ta alloy.The order of the strength of cavitation damage is: silica dioxide,silicon carbide,pure water and aluminum.