激光快速制备Tix Aly-TiN复合涂层

采用激光气体氮化与同步送粉相结合的工艺方法,在Ti-6Al-4V合金表面原位合成了Tix Aly-TiN复合涂层。通过XRD,SEM,OM,EDS,显微硬度测试等手段研究了该复合涂层的物相组成、显微组织、元素分布及显微硬度。结果表明：涂层主要由TiN和Tix Aly 金属间化合物组成；沿激光熔深方向TiN含量下降；Tix Aly 金属间化合物含量上升；涂层无裂纹和孔隙,厚度较均匀,涂层与基体间形成良好的冶金结合；沿激光熔深方向N、Al元素的分布均匀；涂层显微硬度得到显著提高,且从涂层到基体逐渐降低。

Laser Rapid Preparation Tix Aly-TiN Composite Coating

The Tix Aly-TiN composite coatings were in-situ synthesized on Ti-6Al-4V alloy surface by using laser nitriding method. The phase composition, microstructure and microhardness were invesitigated. The results show that the coating is mainly composed of TiN reinforced particles and Tix Aly intermetal matrix. With increase of the depth from the coating surface, the volume fraction of TiN phase decreased and that of Tix Aly intermetal matrix increased. Moreover, the size of the TiN phase and the microhardness value of the coat-ing decreased with increase of the depth from the coating surface. The microcracks and pores cannot be found in the coating. The thick-ness of coating is uniform, and forms a good metallurgical combination between coating and substrate. Along the direction of laser melt-ing depth, the elements of N and Al distribute evenly. The microhardness of coating increases significantly, and gradually reduces from coating to the substrate.