Study On Ring Diamond Wire Saw Cutting Technology For KDP Crystal

KDP crystal is the only suitable optical crystal in inertial confinement nuclear fusion device.With the development of controllable nuclear fusion technology in China,the demand for KDP crystal has increased year by year.In this paper,the physicochemical properties of KDP crystals were analyzed,and the cutting research was carried out.It was found that the "soft and brittle" properties brought great difficulties to the processing.The electroplated diamond wire cutting technology used in this paper has the advantages of high cutting efficiency and good quality,and is widely used in the cutting of brittle materials.The diamond wire saw used is a low-rigidity tool,which can effectively avoid KDP crystal cracking caused by machine vibration and the like.In this paper,the cutting mechanism of electroplated diamond wire saw is analyzed.The influence of wire sawing speed and feed rate on the surface quality and material removal rate of electroplated diamond wire saw cutting process is explored.It is found that high-speed cutting is to improve the cutting surface quality and cutting efficiency.One of the effective ways.This paper analyzes the advantages and disadvantages of three common diamond wire saw cutting machine structures(reciprocating,one-way reciprocating,one-way circulating),and finds that the one-way circulating diamond wire saw machine can be cut at high speed without reversing.The advantages of wire saw wire speed stability,etc.,can achieve precision ultra-precision cutting of hard and brittle materials,which is the mainstream of future development.The one-way circular wire saw cutting technology uses a circular wire saw as the cutting wire to effectively avoid the reversing action during the cutting process and ensure the stability of the wire sawing speed,so that a better surface quality can be obtained.Among them,the ring-shaped electroplated diamond wire saw is an important part of the one-way circular wire saw cutting machine.How to obtain the long-life,high-quality ring-consolidated diamond wire saw base material is a research difficulty.In this paper,a trial development of a ring-shaped electroplated diamond wire saw was carried out:the piano wire was welded into a ring by welding,and the diamond abrasive grain was electroplated by a sanding method.At the same time,the performance of the test was tested.It was found that the heat-affected zone near the solder joint could not meet the original machine tool operating parameters even after heat treatment.In order to avoid the defects of insufficient fatigue strength near the ring wire solder joint,this paper transforms the existing machine tool.Through the fatigue failure mechanism of the wire saw,it is found that increasing the radius of the wire wheel and reducing the number of wire wheels can effectively improve the service life of the wire saw.Based.on the XJ-850×1200 circular diamond wire saw cutting machine platform of the Crystal Materials Laboratory of Shandong University,this paper reconstructs the design.Due to the size limitation,four isometric ladders with a diameter of 350 mm(1 drive wheel,2 driven wheels,1 tensioner)are used.The cutting test of KDP crystal was carried out to study the effects of wire sawing speed,feed rate and tension on the surface quality of KDP crystal cutting.Due to the large number of experimental variables,this pap er uses the orthogonal control variable method.Through experiments,it is found that the higher the speed of the wire saw,the smaller the feed rate and the appropriate reduction of the tension,the better the quality of the cut surface.However if the tension is too small,the cutting of the wire saw will be severely skewed,and the feed rate will be too small,which will result in too low cutting efficiency.Therefore,increasing the speed of the wire saw and achieving high speed and ultra high speed cutting are the most effective factors for improving the cutting effect of the KDP crystal.