Preparation of ZrB_2-MoSi_2 high oxygen resistant coating using nonequilibrium state powders by self-propagating high-temperature synthesis
Preparation of ZrB_2-MoSi_2 high oxygen resistant coating using nonequilibrium state powders by self-propagating high-temperature synthesis
复制标题
非平衡态粉末自蔓延高温合成制备ZrB_2-MoSi_2高抗氧涂层
DOI：
10.1007/s40145-021-0485-y
复制
发表时间：
2021
影响因子：
16.9
通讯作者：
Feng Peizhong
中科院分区：
文献类型：
--
作者：
Zhang Menglin;Ren Xuanru;Zhang Mingcheng;Wang Songsong;Wang Li;Yang Qingqing;Chu Hongao;Feng Peizhong
为了使ZrB_2-MoSi_2涂层在碳结构材料上具有高阻氧结构，以自蔓延高温合成（SHS）技术合成的ZrB_2-MoSi_2复合粉体为原料，采用火花等离子烧结（SPS）法制备了ZrB_2-MoSi_2涂层。研究了ZrB_2-MoSi_2涂层在1973 K下的阻氧机理。与工业粉末相比，SHS粉末制备的涂层具有更高的密度和更低的氧化活性，显著提高了涂层在活性氧化阶段的结构阻氧能力，从而具有更高的氧化防护效率。MoSi_2含量的增加有利于过渡金属氧化物纳米晶（5 ~ 20 nm）在SiO_2玻璃层中的分散，导致黏度增加，从而增强了复合玻璃层在惰性氧化阶段的惰化作用。而SHS粉末制备的ZrB_2-40 vol%MoSi_2涂层样品的氧渗透率最低，为0.3%，碳损失率为0.29×10~(-6) g·cm~（-2）·s~（-1）。由于涂层内部存在梯度氧分压，在复合玻璃层下形成贫硅层，造成急性氧侵蚀。
To achieve high oxygen blocking structure of the ZrB_2-MoSi_2 coating applied on carbon structural material, ZrB_2-MoSi_2 coating was prepared by spark plasma sintering(SPS) method utilizing ZrB_2-MoSi_2 composite powders synthesized by self-propagating high-temperature synthesis(SHS) technique as raw materials.The oxygen blocking mechanism of the ZrB_2-MoSi_2 coatings at 1973 K was investigated.Compared with commercial powders, the coatings prepared by SHS powders exhibited superior density and inferior oxidation activity, which significantly heightened the structural oxygen blocking ability of the coatings in the active oxidation stage, thus characterizing higher oxidation protection efficiency.The rise of MoSi_2 content facilitated the dispersion of transition metal oxide nanocrystals(5-20 nm) in the SiO_2 glass layer and conduced to the increasing viscosity, thus strengthening the inerting impact of the compound glass layer in the inert oxidation stage.Nevertheless, the ZrB_2-40 vol%MoSi_2 coating sample prepared by SHS powders presented the lowest oxygen permeability of 0.3% and carbon loss rate of 0.29×10~(-6) g·cm~(-2)·s~(-1).Owing to the gradient oxygen partial pressure inside the coatings, the Si-depleted layer was developed under the compound glass layer, which brought about acute oxygen erosion.