| With the continuous progress and development of modern engineering,higher requirements are put forward for modern engineering materials.In the field of modern engineering,materials are usually required to have the characteristics of light-weight and high strength to reduce the mass of materials as much as possible on the basis of meeting the strength requirements.Lighter material quality often means less energy consumption for the field of machinery and transportation engineering,which is great significance for energy conservation and emission reduction and realizing the national strategic objectives of"carbon peak"and"carbon neutralization".Therefore,the traditional metal materials can not meet the requirements of modern engineering for light-weight and high strength because of their relatively bulky characteristics.Because of their light-weight,good strength and toughness,resin matrix composites gradually replaces traditional structural materials.They are known as a dazzling"new star"in the field of engineering materials.They are widely used in aerospace,rail transit,automobile industry,sports and entertainment and many other fields.In the resin matrix composites,the fibers used to strengthen the resin matrix mainly include carbon fiber,glass fiber,basalt fiber,aramid fiber and so on.Although carbon fiber has been developed for many years and has good mechanical properties,it is expensive and not suitable for all occasions;Similarly,the mature glass fiber do not conform the current concept of green development because of its toxic,harmful and polluting characteristics;In contrast,basalt fiber has better mechanical properties than glass fiber,low price and environment-friendly characteristics,which has attracted more and more attention.Therefore,this paper selects basalt fiber and epoxy resin commonly used in engineering to design lightweight,high strength and toughness composites.In nature,organisms have achieved the unity of light-weight,high strength and toughness through billions of years of evolution.Mantis shrimp is a typical example.Mantis shrimp can be divided into"piercing type"and"crushing type"according to their different stomatopod dactyl club.The dactyl club at the end of the knuckle of the"crushing"mantis shrimp is hammer shaped.When it preys,its claw stick can produce a very high instantaneous speed,up to 23m/s.It can break extremely hard shells and has extremely high strength and extremely light weight;"Piercing"mantis shrimp has a spear shaped dactyl club at the end of its knuckles.It preys on its prey by stabbing.Its stabbing speed can reach 8m/s.It mainly bears bending and shear loads in the process of predation,and also has high strength and toughness.These two kinds of mantis shrimp will produce high instantaneous speed when attacking prey,so a large amount of energy will be transmitted to other tissues through the mantis shrimp's claw rod.There is a saddle shaped exoskeleton above the mantis shrimp's attached foot carpal bone to realize the slow-release and effective dissipation of impact energy,which has high toughness.Therefore,mantis shrimp is selected as the biological model for biomimetic composite design in this paper.In this paper,the mantis shrimp dactyl club with light-weight and high strength characteristics and the mantis shrimp saddle shaped exoskeleton with high toughness characteristics are selected as the research objects.They are deeply studied from the aspects of material composition,microstructure and mechanical properties,and their corresponding strength and toughness mechanism is revealed.Taking this as the bionic prototype,the bionic high strength and toughness materials are designed and prepared by using basalt fiber.In terms of the mechanism of light-weight and high strength and toughness of biomaterials:(1)The two mantis shrimp dactyl club and their load environment through comparing the characteristics of them,it is determined that the mantis shrimp through comparing the characteristics of have the characteristics of light weight,high strength and bending shear resistance,while the hammer mantis shrimp claws have the characteristics of light weight,high strength and bending resistance.It is revealed that the light-weight and high strength,bending and shear resistance of the mantis shrimp spear is mainly the result of the joint action of the fiber arrangement of its spiral structure and the gradient density distribution;The light-weight,high strength and impact resistance of mantis shrimp smasher is mainly due to the stress homogenization effect of sinusoidal fiber structure and energy dissipation of spiral fiber structure.(2)By analyzing the mechanism of saddle shaped exoskeleton of two kinds of mantis shrimp,it is revealed that the energy release characteristics and high toughness are mainly the result of the synergistic toughening of spiral fiber structure and interlayer fibril structure.Through the analysis and research of mantis shrimp dactyl club and saddle shaped exoskeleton,it provides a solid theoretical support for the design and preparation of biomimetic composites.Based on the analysis of the high strength and toughness mechanism of biomaterials,this paper further analyzes the similarities and differences between the biological living environment and the actual situation of composites,extracts the key elements for bionic design,establishes the corresponding engineering model,and designs the bionic composites for different load environments based on the engineering model through the analysis and optimization of the engineering model.Through a series of means such as numerical simulation and analysis,experimental testing and so on,this paper explores the effectiveness of scale effect on practical engineering materials,and reveals the complex failure process of bionic composites.The design and manufacture of composite materials based on the high strength and toughness mechanism of mantis shrimp biomaterials are mainly divided into the following aspects:(1)For the mantis shrimp spear,the spiral structure is extracted as the key feature,and the corresponding engineering model is established.After screening and optimizing the parameters of the model,the corresponding bending and shear composite materials are prepared by hot pressing with prepreg,in which the bionic composite with interlayer angle of 18°has the best comprehensive bending performance(1010.1±46.4Mpa),and the specimen with interlayer angle of 22.5°has the best comprehensive interlayer shear strength(21.67±0.84Mpa).(2)For the mantis smasher,the sinusoidal-helical composite fiber structure is selected as the key feature,and the corresponding engineering model is established.After selecting and optimizing the parameters of sinusoidal fiber structure and helical fiber structure respectively,it is determined that the interlayer angle of the helical fiber structure is 15°,and the stripe width of the sinusoidal fiber structure is 4mm,so as to make the corresponding bionic impact resistant composites by vacuum diversion method.Its impact toughness can reach199.8k J/m~2,which is about 45%higher than that of traditional samples.(3)For the saddle shaped exoskeleton of mantis shrimp,the spiral fiber structure and interlayer filament structure are selected as the key characteristics.The corresponding bionic model is established to obtain better parameters.The corresponding bionic high toughness composites are made by using electrospinning technology and vacuum diversion method.The type I and type II interlayer fracture toughness are increased by about 44%and 118%respectively.Based on the biological high strength and toughness mechanism of mantis shrimp and saddle shaped exoskeleton,the composite is designed and prepared,which significantly improves the mechanical properties of the composite and provides exploration and reference for the practical engineering application of bionic composite.Based on the previous design of high strength and toughness composite materials,inspired by biological perception of pain and damage,a new lightweight high strength and toughness composite material with high strength and toughness and damage self-monitoring function is designed and manufactured.This material not only has high strength and toughness,but also has the ability of self-monitoring engineering damage.It is applicable to key engineering parts that need to have the functions of light-weight,high strength and toughness and material damage monitoring at the same time.This paper studies and analyzes its response characteristics to different forms of damage and failure.To sum up,the main innovation of this paper is:starting from the biological characteristics,making innovative research on the applicable load environment and the high strength and toughness mechanism behind it.According to the mechanism of light-weight and high strength and toughness,the composite materials suitable for different working conditions,such as bending shear resistance,impact resistance and high toughness,are designed.According to different working conditions,the design and manufacture of high strength and toughness basalt are innovatively studied.Finally,inspired by the biological perception of pain and injury,a bionic composite applied to key parts is developed,which makes corresponding research and exploration for the design and application of new intelligent engineering materials. |
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