Study On Bionic Design And Mechanical Properties Of Basalt Fiber Disc Spring

In recent years,the isolation device with disc spring has become an important part in the field of architecture,and it plays an important role in the energy absorption of buildings.Therefore,it is of great significance to enhance the ability of isolation and energy absorption by increasing the load and stiffness of the disc spring.Disc springs are traditionally made of metal,and there are some problems of heavy weight,easy corrosion and increased post-maintenance.As a new kind of material,composite materials have excellent characteristics of light weight,corrosion resistance and outstanding mechanical properties,it has a good application prospect to replace metal disc spring with composite disc spring.With condition of same size,the load value of composite disc spring is often lower than that of metal disc spring.Therefore,it is of great significance to improve the load of composite disc spring.In the nature,the exoskeletons of crustaceans are relatively hard,and they have excellent mechanical properties.This phenomenon is mainly related to their special helical layer structure.In this paper,we were inspired by helical layer structure of exoskeletons?mantis shrimp?of crustaceans to explore the influence on the load of composite disc spring by changing the layer angle of composite material.The results of the research were as follows:?1?Unidirectional basalt fiber disc spring:with finite element?FE?analysis,we found that the load value of unidirectional basalt fiber disc spring with 90°helical layer angle was maximum,the load value increased by 63.6%compared to the balanced symmetrical layer angle with 45°?the layer angle with minimum load?.The results showed that the layer angle had a great influence on the load value of the basalt fiber disc spring.However,according to the maximum stress theory,they were both failed about unidirectional basalt fiber disc springs with the helical layer angle and balanced symmetrical layer angle during compression.The unidirectional basalt fiber disc springs with a helical layer angle of 90°?the layer angle with maximum load?were formed,and the compression tests were carried out.The load values of the disc springs obtained by the experiment were basically consistent with the FE analysis with the difference of 8.6%.The crack was found on the surface of the disc spring after the compression.Thus,the failure analysis of maximum stress theory was verified,and it proved that the compression performance of unidirectional basalt fiber disc spring was unstable and it was prone to fail;.?2?Diagonal composite disc springs:with FE analysis,we found that the load value of diagonal basalt fiber disc spring with 0°helical layer angle was maximum,the load value increased by 58.6%compared to balanced symmetrical layer angle with 45°?the layer angle with minimum load?.According to the maximum stress theory,there were no failure behavior of diagonal basalt fiber disc springs with the helical layer angle and balanced symmetrical layer angle during compression.Commonly used composite materials also include glass fiber and carbon fiber composite materials.In order to further increase the load value of the disc spring,the mechanical properties of diagonal glass fiber disc spring and diagonal carbon fiber disc spring under the layer angle with maximum load values were analyzed by FE analysis,and it found that the load values of glass fiber disc spring and carbon fiber disc spring were 4.4%and 45.0%higher than that of the basalt fiber disc spring,respectively.The diagonal basalt fiber,glass fiber and carbon fiber disc springs with the helical layer angle of 0°?the layer angle with maximum load?were obtained by experiment,and the compression tests were carried out.It found that the load values of three kinds of composite disc springs were basically consistent with the FE results,and the difference was less than 10.0%.There was no crack on the surface of the basalt fiber disc spring after compression.It was consistent with the failure analysis of maximum stress theory,which proved that the diagonal composite disc springs had better compression stability and higher safety margin compared to unidirectional basalt fiber disc spring;?3?Composite disc springs:the load of the single disc spring often does not reach the requirements of application.In order to further increase the load value of disc spring,the combined disc springs were proposed.Taking basalt fiber disc spring as the research object,the diagonal basalt fiber disc spring with more stable mechanical properties were combined with different combination types,the mechanical properties of combined disc springs with different friction coefficients were studied by FE analysis.It found that load values of combined disc springs with congruence combination,involutive combination and compounded combination were both higher than that of single disc spring.The load values of the combined disc springs gradually enhanced with the increase of friction coefficient.Three kinds of composite disc springs including diagonal basalt fiber,glass fiber and carbon fiber disc springs were also tested with experiment,and the above-mentioned disc springs were combined with congruence combination and involutive combination.They were tested in the condition of the dry friction?without lubrication medium?and the addition of MoS₂lubricant with compression test.The maximum load values obtained by experiment of combined disc springs were consistent with FE results,and the difference was within15.0%.It showed that in congruence combination,the maximum load values of diagonal basalt fiber,glass fiber and carbon fiber disc springs with MoS₂ lubricant were 19.8%,15.4%and 9.0%lower than those without MoS₂ lubricant,respectively.In involutive combination,the load values of three kinds of disc springs with MoS₂lubricant were 6.3%,8.2%and 7.0%lower than those without MoS₂ lubricant,respectively.Thus,the friction had a great effect on the load values of disc springs.With the increase of friction,the load values of the combined disc springs also increased,but the increase of the friction could reduce the service life of the disc spring.