面向国家“推进资源循环利用和加强固体废弃物处理”的重大战略，针对大量废弃硅钼棒未能有效利用的问题，在前期选择性回收的基础上，提出废弃硅钼棒“全物质利用”的新思想，即以废弃硅钼棒为原料，采用等离子喷涂技术在钼合金表面制备耐高温涂层，使废弃硅钼棒得到整体再利用，实现零废物排放。为此，本项目将确定废弃硅钼棒的相组成、元素存在形式和分布状态，探明不同相的含量；建立并优化废弃硅钼棒粉末的等离子喷涂工艺，确立相关参数，明确喷涂过程原料颗粒的演化机制，揭示涂层的构建原理；阐明涂层的组织结构，明晰界面结合特征和性能；重点澄清涂层的高温静态氧化、循环氧化特性，理解Mo、Si、O等化学元素的迁移路径及其相结构的进展和转化规律，探明表面膜的成膜机理和表面膜/涂层/基体三界面发展规律，揭示涂层的抗高温氧化机制。为废弃硅钼棒的全物质再利用，建立“无废硅钼棒”理念，甚至构建“无废社会”提供必要的理论依据和技术支持。

In response to the national call for "promoting the recycling of resources and improving the treatment of solid waste", especial for the rare metal of molybdenum, moreover for waste MoSi2 heating elements, we create the novel idea for the recovering and reusing the waste MoSi2 heating elements without any separation and remove, which is not a selective recycling, and it is a 100% reusing. The waste MoSi2 heating elements will be the raw materials for the high-temperature anti-oxidation coating on the Mo-based alloys by atmospheric plasma spraying (APS), and the coating construction principle and high temperature anti-degradation mechanism will be pursued..The waste MoSi2 heating elements will be determine by advanced material methods, such as XRF, XRD, SEM, EPMA, etc. The phase composition, the mapping and contents of chemical elements and the microstructure will be investigated. The waste MoSi2 heating elements will be ground to the particles with the size about 100 μm, and as a candidate, the particles will be ground to the powders with the size of 5-10 μm, and then the agglomerated powders is prepared using a centrifugal spray drying and high-temperature treatment. The as-prepared powders were deposited on Mo substrates via APS, and the parameters of APS will be studied, and the phase and microstructure evolution of APS powders will be discussed, and the physical model will be founded. The waste MoSi2 coating will be characterized by SEM, TEM, 3D-XRM, XPS, etc, furthermore, the coating surface composition, valence state will be studied, and the cross-section microstructure will be analyzed, and the interface between the coating and substrates will be investigated..The static and cyclic oxidation test will be conducted in air from 1200 to 1500 ℃, the oxidation kinetic curve will be built, and the microstructure and chemical compositions development of the coating will be analyzed using SEM and EPMA, in addition, the interface of surface/coating/substrates will be investigated, the mapping and diffusion path of the chemical elements of Mo, Si and O will be revealed. The formation and growth mechanism of surface scale for the coating will be discussed. The oxidation-resistant and thermal shock performance and degradation mechanism for waste MoSi2 coatings at high-temperature are concluded..The present work will develop the novel recycling of waste MoSi2 heating elements, in particular, without any separation and removing, which is strong beneficial to the strategy of "no-waste society".