Super-elasticity Design And Preparation Of NiTi Alloy Abortion Equipment

At present the main methods of pregnancy termination in our country are artificial abortion and drug-induced abortion, while the equipment of artificial abortion is mainly based by vacuum aspiration, that is, under negative pressure using a hard pipe to remove product of the pregnancy to make the termination of pregnancy, the biggest problem of vacuum aspiration is the expansion of cervical and uterine perforation, the vacuum aspiration flow instruments used in structural design, material selection to solve the above problems have a very important practical significance. Because of nickel-titanium shape memory alloy super-elasticity and excellent biocompatibility, as a new type material in artificial abortion nickel-titanium shape memory alloy is feasible.This paper chooses nickel-titanium shape memory alloy as the main instruments of abortion material, designs a kind of basket-type device termination of pregnancy, mainly including sheath, guide wire, basket and handle four parts. Using a nickel titanium alloy basket wilthout sharp objects remove the intrauterine pregnancy to terminate pregnancy, which avoid negative pressure, the original principle of expansion of cervical mouth, rigid catheter can not adapt to the uterus position and the shape of varicose and scraping through the second pull-out of uterine cavity.ANSYS software is used in this paper to calculate mechanical structure of nickel-titanium device. The results showed that in a given constraint case, the nickel-titanium device designed the mechanical structure. Through the use of nickel titanium wire basket carried out martensite phase and tensile properties of research, determine the shape of nitinol basket heat treatment at 520℃insulation 10min. This paper specifically designs a mold for nickel-titanium shape basket devices and laser welding, through the organizational analysis of welding, the welding performance comparison after the tensile test and fracture surface analysis, determine the basket of nickel-titanium laser welding technology, and prepare of the main part of anickel-titanium device-basket. This paper has completed the nickel-titanium alloy basket preparation, obtain a nickel-titanium super-elastic and the best welding process parameters, provide a technical basisfor the device in the clinical end abortion applications.