%A CAI Wenjun, LU Wenzhuang, WANG Han, ZHU Yansong, ZUO Dunwen %T Microstructure and property of surface layer produce during rare earths solid-state boriding of TC21 titanium alloy %0 Journal Article %D 2015 %J Acta Aeronautica et Astronautica Sinica %R 10.7527/S1000-6893.2014.0206 %P 1713-1721 %V 36 %N 5 %U {https://hkxb.buaa.edu.cn/CN/abstract/article_15667.shtml} %8 2015-05-15 %X

The rare earths (RE)-boronizing experiments are carried out for surface strengthening of TC21 titanium alloy. Microstructure, hardness, worn surfaces and specific wear rate of boride layers are studied. Results show that the boride layer with 7wt% content of CeO2 in the agent is continuous and compact and it has better wear resistance. Boronizing temperature has a significant effect on the thickness of TiB2 layer and the thickness of boride layer tends to significantly increase with it. As boronizing time goes on, the TiB2 layer in surface becomes deeper and more continuous, whereas the thickness of boride layer increases slowly after a certain time. The microhardness of top layer is significantly increased by raising boronizing temperature, but it rises gently with time passing. At 1 000 ℃, the microhardness of top layer is about 3 200 HV0.01 and the depth of high microhardness area is over 20 μm. The boride layer has a good wear resistance and specific wear rate of boride layers is 50-60 times lower than that of untreated specimen.