目的 使Al/NiCr复合涂层之间发生改性反应，并原位生成具有一定抗氧化性能的Ni-Al金属间化合物防护涂层。方法 利用电弧喷涂结合等离子喷涂的工艺方法在工业纯钛表面制备了Al/NiCr组合涂层，对喷涂态Al/NiCr/Ti试件于炉中进行700 ℃加热改性处理，研究了加热改性处理前后涂层的微观组织形貌及Ni-Al金属间化合物的形成机理。此外，还对经加热和打磨处理后的Al/NiCr/Ti试件及无防护涂层的Ti块进行了800 ℃/100 h的高温氧化试验。结果 Ti基体表面Al/NiCr涂层经700 ℃炉中加热改性处理后，Al、NiCr涂层之间发生改性反应，并原位生成了固溶有一定Cr元素的Ni2Al3及NiAl金属间化合物。另外，在整个Al、NiCr扩散反应区中，弥散分布有Al液和Cr2O3、NiO组成的混合物组织。但是生成的Ni2Al3相金属间化合物有熔化现象发生，只有高熔点的NiAl金属间化合物能够稳定存在。结论 经改性反应所得的NiAl金属间化合物层对Ti基体起到了较好的高温防护作用。

The work aims to promote the modified reaction between Al/NiCr composite coatings and prepare a Ni-Al intermetallic compound protective coating with certain oxidation resistance through in-situ reaction. The Al/NiCr composite coatings were deposited on the surface of pure Ti substrate by arc spray technology and plasma spray technology, the sprayed Al/NiCr/Ti specimen was then heated in the furnace at 700 ℃, and the microstructure of the coatings before and after heat modification treatment and the formation mechanism of Ni-Al intermetallic compounds were studied. In addition, the oxidation tests of the Al/NiCr/Ti specimen (after heating and polishing treatment) and the uncoated Ti were conducted at 800 ℃ for 100 hours. By modifying Al/NiCr spray coatings on Ti substrate through furnace heating treatment at 700 ℃, Ni2Al3 and NiAl intermetallic compounds with certain Cr elements were formed through in-situ reaction between Al/NiCr composite coatings. In addition, the mixture organizations of Al liquid and Cr2O3 and NiO were dispersed in the entire Al and NiCr diffusion reaction zone. However, the generated Ni2Al3 intermetallic compound melted, and only the NiAl intermetallic compound with high melting point could exist stably. The NiAl intermetallic compound layer obtained by the modification reaction has a good high temperature protection effect on the Ti substrate.