铝热-离心法制备TiC/FeNiCr复合涂层的耐热性研究

Study on Heat-Resistance of TiC/FeNiCr Composite Coating Produced by Centrifugal-Thermite Process

采用铝热．离心工艺在碳钢钢管内表面制备了TiC／FeNiCr金属陶瓷涂层。借助XRD，DSC，FESEM和显微硬度仪等方法研究涂层材料经历不同加热时间后的组织及结构稳定性，并利用等离子烧蚀实验测量涂层的耐烧蚀性能。结果表明，涂层材料由口．FeNiCr，TiC，NiAl及Nj3Al4相组成，基体组织细小致密，无粗大枝晶，没有微裂纹；经加热处理后，基体α-FeNiCr中弥散分布的TiC相尺寸无明显变化，材料显微硬度略有降低：由室温加热到1300℃过程中，材料不会发生相变；TiC／FeNiCr涂层的线烧蚀率为4．53μm／s，抗烧蚀性能比45^＃碳钢提高了32％。

The TiC/FeNiCr coating was prepared by centrifugal-thermite process in a carbon steel pipe. The microstructure stability of the coating at elevated temperature was investigated by means of XRD, DSC and SEM. The ablation-resistance property of the coating was measured by plasma ablation test. Results show that the TiC/FeNiCr composite was composed of a-FeNiCr, TiC, NiAl and Ni3Al. The structure of the coating was thin and compact, having no large dendritical crystals, microcracks and micropore. In the heating process below 1300 ℃, phase transformation had not been found. After the heating process, the grain size of the TiC nearly didn＇t grow, the hardness of the material got slightly lower. The line ablation rate of the TiC/FeNiCr layer was 4.53 μm/s, raised 32% compared with the 0.45C% steel.