Experimental Study On Grinding Of Nickel-based Superalloy And Polishing Of Magnetorheological Elastomer

Nickel-based superalloys have been widely used in aerospace,nuclear energy,ship preparation and other industries due to their high temperature strength,thermal fatigue resistance,and acid and alkali corrosion resistance.However,as a typical difficult-to-machine material,the traditional grinding process of nickel-based superalloy has the disadvantages of high processing cost,processing efficiency and low processing quality.How to improve the grinding performance of nickel-based superalloys and improve the surface integrity of workpieces after grinding has always been a concern of the Institute of Grinding and Processing of Nickel-base superalloys.This paper puts forward the research ideas for polishing nickel-based superalloys with flexible rubber wheels using silicon rubber magnetorheological elastomers as the matrix.Based on the grinding process tests of nickel-based superalloys,the construction of a magnetorheological elastomer grinding wheel polishing test platform was established.Conducted magnetic field-assisted polishing experimental research on nickel-based superalloys,and systematically studied and analyzed the preparation process and magnetomechanical properties of magnetorheological elastomer wheels,and finally demonstrated the magnetic field of magnetorheological elastomer wheels Under the condition of auxiliary polishing,it can effectively improve the surface integrity of the material after grinding.The main research contents of this article are as follows:(1)Describes the research status of nickel-based superalloy grinding at home and abroad.In view of the current research status of grinding processing,the idea of magnetorheological elastomer grinding wheel polishing nickel-based superalloy is proposed in order to achieve the improvement of grinding surface The effect of completeness,at the same time,reviews the current status of research on magnetorheological elastomers at home and abroad,and finds that magnetorheological elastomers have certain research prospects in the field of polishing.(2)The grinding surface integrity test of nickel-based superalloys GH4169 and DD6 was carried out.The grinding test was carried out with CBN,white corundum,and diamond wheels.The test used a single factor test method to study the wheel speed,the influence rules of workpiece feed rate,grinding depth,grinding wheel particle size and grinding wheel type on the surface morphology,surface roughness,and microhardness of the workpiece after grinding,and the corresponding research on grinding removal rate.(3)The nickel-based superalloy scoring model was established,and the scratch test was carried out on the nickel-based superalloy GH4169.The test used two different loading methods,namely constant load and variable load.The scoring length under load is 3mm,and the scoring length under variable load is 6mm.The test analyzes the effect of loading load and scoring speed on friction and acoustic emission signals.At the same time,the scratch contour curve and scratch shape were analyzed and discussed.(4)First,a set of polishing test device suitable for magnetorheological elastomer grinding wheel polishing nickel-based superalloy was designed and built,a set of preparation molds for magnetorheological elastomer grinding wheel was designed,and magnetorheological elastomer grinding wheel was prepared.Then the microstructure and hardness of the magnetorheological elastomer wheel are characterized.At the same time,the magnetic friction and wear performance of the grinding wheel sample was characterized,and the effects of magnetic field strength and loading load on the friction coefficient and wear scar profile were studied.Finally,the effect of magnetic field strength on the integrity of the polished surface is studied.