Ni_2Cr(BO_3)O_2涂层的制备及其红外发射性能

Preparation and Infrared Emissivity of Ni_2Cr(BO_3)O_2 Coating

通过喷雾造粒和高温焙烧制备Ni_2Cr(BO_3)O_2粉末后利用等离子喷涂得到一种高红外发射涂层,并研究了该种涂层的红外发射性能。SEM观察涂层的表面、断面形貌,发现涂层与基体结合紧密、无脱落;XRD对焙烧后的粉末物相组成进行了表征,主要以Ni_2Cr(BO_3)O_2为主。对涂层红外波段发射率的测试表明,在0.76~2.5μm波段的发射率为0.896、2.5~14μm波段发射率为0.925,具有优异的红外发射性能。Ni_2Cr(BO_3)O_2晶胞内的畸变、非对称性以及电子转移跃迁是导致Ni_2Cr(BO_3)O_2这种材料具有高红外发射率的主要原因。Ni_2Cr(BO_3)O_2涂层能够经受37次"900℃~水冷"热震循环。该种涂层由于其高红外发射性能、优异的耐热震性能和热稳定性能而具有较高的实用价值。

Ni2Cr（BO3）O2 coating, a high infrared emitting coating, was prepared via atmospheric plasma spraying after Ni2Cr（BO3）O2 powder was prepared by spray granulation and calcining at high temperature. The infrared emissivity of the coating was studied. The surface and section morphology of the coating were observed by SEM and it is found that the coating is closely combined with the matrix. The phase composition of calcined powder was characterized by XRD, mainly containing Ni2Cr（BO3）O2. According to test result, infrared emissivity of the Ni2Cr（BO3）O2 coating in the wave band of 0.76-2.5 μm is 0.896 while that in the wave band of 2.5-14 μm is 0.925, which indicates that the coating possesses excellent infrared emission performance. Lattice distortion, asymmetry and electron transfer transition in the Ni2Cr（BO3）O2 structure cell are the main reasons for high infrared emissivity. Ni2Cr（BO3）O2 coating can withstand thermal shock circles of 37 times from 900℃ to 20℃ of water. The coating has high practical application value due to its high infrared emissivity, good thermal shock resistance and thermal stability.