摘要
激光武器进入实战应用阶段,空天武器的抗激光防护研究迫在眉睫。高能激光长时间辐照,造成如金属反射层氧化反射率降低、烧蚀层质量损失、隔热层韧性不足等问题。基于此,提出一种综合利用反射和隔热原理的复合型激光防护策略。通过调控喷涂功率、喷涂距离等参数,采用超音速火焰喷涂技术和等离子喷涂技术分别制备了NiCoCrAlTaY粘结层、氧化钇稳定氧化锆(YSZ)面层的双层涂层,探究表面粗糙度与孔隙率对反射率的影响规律,并考察了涂层的激光防护性能。结果表明:喷涂功率或喷涂距离越大,涂层的层状效果越明显,断面孔隙越多。涂层表面粗糙度随喷涂距离的增大先降低后增加。去除二次反射结构后的涂层表面Ra=1.8μm,当Ra=0.5μm时,涂层中的楔形结构使涂层反射率相较于Ra=1.8μm时的反射率提升了约2.4%。指出层状孔隙是高反射楔形结构的关键,球形孔隙是激光吸收点,孔隙率14.7%的工艺参数(39 kW,100 mm)为最优。在激光烧蚀试验中,激光功率密度的增加,涂层裂纹逐渐增多,直至烧蚀孔洞,线烧蚀率近似抛物线增长。低激光功率密度条件下(<3800 W/cm^(2)),表层组织轻微变化,功率增大,表层裂纹增多加深,重凝区花瓣状组织增大;大功率激光密度(>8050 W/cm^(2))条件下,涂层表层部分剥离与烧蚀孔洞致使涂层失效。
Laser weapons have entered the actual combat application stage,and the research on antilaser protection for air and space weapons is becoming increasingly urgent.Prolonged highenergy laser irradiation leads to problems such as reduced metal reflectance,mass loss of ablated layer of the ablative layer and insufficient heat insulation toughness.Based on this,a composite laser protection strategy based on the principles of reflection and heat insulation was proposed.In this study,by adjusting spraying power,spraying distance and other parameters,supersonic flame spraying technology and plasma spraying technology were used to prepare NiCoCrAlTaY bond coating and yttriastabilized zirconia(YSZ)top coating doublelayer coatings,to explore the influence of surface roughness and porosity on reflectivity,and to investigate the laser protection performance of the coatings.Results showed that the larger the spraying power or spraying distance,the more obvious the layer effect,and the more crosssectional pores were observed in the coating.The surface roughness of the coating decreased first and then increased with the increase in spraying distance.When the secondary reflection structure was removed,the coating surface had Ra=1.8μm.When Ra=0.5μm,the wedgeshaped structure of the coating increased the reflectivity by about 2.4%compared to that of the coating when Ra=1.8μm.It was pointed out that the layered pores were key to the highreflection wedge structure,the spherical voids were the laser absorption points,and the process parameter of 14.7%porosity(39 kW,100 mm)was the best.In the laser ablation experiment,with the increase in laser power density,the cracks in the coating gradually increased until holes were ablated.The line ablation rate increased approximately in a parabolic manner.With low laser power density(<3800 W/cm^(2)),the surface structure changed slightly;as the power increased,the surface cracks increased and deepened,and the petallike structure in the recondensing zone increased.With high laser power density(>8050 W/cm^(2)),partial peeling and ablation of the coating surface caused the coating to fail.
作者
李书文
吴凌峰
杨冠军
陈林
LI Shuwen;WU Lingfeng;YANG Guanjun;CHEN Lin(State Key Laboratory for Mechanica,Behavior of Materias,Xi’an Jiaotong,University,Xi’an 710049,China;Shanghai Institute of Space Propulsion,Shanghai 201100,China)
出处
《材料保护》
CAS
CSCD
2024年第12期84-95,共12页
Materials Protection
基金
细喷管内壁高反射-高隔热一体化防护涂层。
关键词
激光防护涂层
等离子喷涂
反射率
防护性能
laser protective coating
plasma spray
reflectivity
protective properties
