【作者】 蒋啸林；

【导师】 陆辛；

【作者基本信息】 机械科学研究总院 ， 机械设计及理论， 2012， 博士

【摘要】 电爆炸定向喷涂法作为一种新兴的热喷涂技术，与传统的热喷涂技术相比具有独特的优势，对利用该技术来提高火炮身管内膛抗烧蚀性的机理进行研究十分具有现实意义。本文对已有的电爆炸喷涂设备进行了适当改造，采用气动装夹方式提高了喷涂效率，自制了环保的除尘系统，减少了有毒烟尘的危害。同时对金属丝电爆炸喷涂的原理及研究现状进行了综述。利用改造后的电爆炸喷涂装置制备了65Mn、0Cr18Ni9Ti、2Cr13涂层,利用光学显微镜和扫描电镜对涂层显微组织进行了观察，分析了显微组织和硬度，结果表明，涂层组织比原始显微组织明显细化，涂层/基体界面结合良好，存在明显的元素扩散现象，涂层的显微硬度比原始硬度显著提高。以0Cr18Ni9Ti涂层为例对喷涂过程中的工艺参数进行了分析，应用多种方法对不同喷涂条件下涂层厚度和孔隙率进行了比较，结果表明：随着喷涂电压的增加涂层的孔隙率降低，涂层的厚度增加，但增加幅值减小；随着喷涂距离的增加，涂层厚度减小，孔隙率增加；随着喷涂次数的增加，涂层厚度增加，孔隙率降低。以涂层FeCrBSi为例，从数值分析的角度对喷涂粒子冲击基体钢板过程中的应力变化情况及粒子的沉积过程进行分析，并通过有限元模拟手段针对不同喷涂距离、不同喷涂次数情况下，喷涂过程中对基体内部的应力影响及涂层厚度、温度的不同对涂层、基体温度及降温速率的影响进行了分析讨论。通过计算得出，电爆炸喷涂过程中产生的冲击波在不同喷涂距离、不同喷涂次数情况下，基体炮钢样片的内部应力变化很小，几乎对基体没有任何破坏。在涂层厚度相同的情况下，涂层初始温度越高，对涂层内同一点温度、温降速率影响越大。对涂层内不同深度处的温度、温度变化率的影响也越大，其中对涂层内靠近基体处影响最大。在涂层初始温度相同的情况下，涂层厚度越薄，对涂层内相同深度处温度、降温速率影响越大；对于涂层不同深度处，涂层内深度较大处的温降速率影响越大，其中对基体内靠近结合面处影响最大。通过对火炮身管内膛表面改性涂层应具备的特性进行分析后，利用电爆炸喷涂的技术优势制备涂层，与现有火炮身管内膛表面抗烧蚀采用的电镀铬镀层进行多项性能对比试验，试验结果表明利用电爆炸喷涂技术可制备出抗烧蚀性能显著优于镀铬层的涂层，从而得出电爆炸喷涂技术用于提高火炮身管寿命的机理研究成果。更多还原

【Abstract】 Electrical explosion directional spraying as a new kind of thermal sprayingtechnology has a unique advantage compared with the traditional hot sprayingtechnology. It is very significant to study the mechanism of using the technology toimprove anti-erosion in artillery barrel life. In this paper, appropriate improvementis made in the existing electric explosion spraying equipment. Pneumatic clampingway is used to improve the efficiency of spraying. The environmental protectivedust removal system is made in order to reduce the harm of toxic smoke. Wireelectrical explosion spraying principle and the present research status is also studiedin this paper.65Mn,0Cr18Ni9Ti,2Cr13coating is prepared by improved electricexplosion spraying equipment. Coating microstructure was observed with opticalmicroscope and scanning electron microscopy (SEM). The microstructure andhardness are analyzed. It is show that the coating organization is refined than theoriginal microstructure, and coating/substrate interface combined well. There isobvious element diffusion phenomenon, and micro hardness of coating issignificantly enhanced than the original hardness.Take0Cr18Ni9Ti coating for example, technological parameters of sprayingprocess are analyzed, the thickness and porosity in different spraying conditions arecompared by kinds of methods. It is showed that: with the increase of sprayingvoltage, coating porosity decreases and coating thickness increases, but the increaseamplitude decrease; Coating thickness decreases and coating porosity increases,with the increase of the spraying distance; Coating thickness increases and coatingporosity decreases with the increase of spraying times.Take FeCrBSi coating for example, using numerical analysis method toanalysis stress changes in the process of spray particle impacting the steel plate anddeposition process of spray particle. The influence of coating thickness, internalstress of substrate and coating temperature on the coating, substrate temperature andcooling rate are discussed by means of the finite element method. Calculations showthat shock wave of electrical explosion spraying process produced in differentspraying distance and times, the internal stress of steel plate substrate changes little,almost without any damage to substrate. When coating thickness is unchanged, thehigher coating initial temperature the greater influence is happened on substrate temperature of similar depth inner, temperature alteration ratio. In different depthsof substrate, the higher coating initial temperature the greater influence ontemperature and temperature alteration ratio of different depth inner substrate, thegreatest influence occur at near junction surface of substrate and coating. In case ofcoating with same initial temperature the thinner coating thickness, the greaterinfluence on temperature and temperature alteration ratio of different depth inner ofsubstrate. In different depths of substrate, the thinner coating thickness the greaterinfluence on temperature and temperature alteration ratio of different depth anddirection inner of substrate, the greatest influence occur at near junction surface ofsubstrate and coating.Some performance contrast test are made between coating prepared byelectrical explosion spraying technology and chromium coating of existingartillery barrel tube surface re-ablation after analysis on the characteristics ofartillery barrel tube surface modification coatings.Coating prepared by electrical explosion directional spraying is significantlybetter than chrome coating in anti-erosion when it is used in artillery chamber. Themechanism research results of improve artillery barrel life by electrical explosionspraying technology are got.更多还原