钛合金表面激光熔覆h-BN固体润滑涂层

发布时间：2018-06-02 05:44

本文选题：激光熔覆 + TC钛合金　；参考：《表面技术》2015年08期

【摘要】：目的优化钛合金激光熔覆固体润滑涂层的熔覆工艺参数,提高钛合金表面耐磨性能。方法采用Nd∶YAG激光器,分别在高功率和低功率条件下,在TC4钛合金表面制备h-BN固体自润滑涂层。观察分析熔覆陶瓷层的宏观形貌、物相组成、显微组织和硬度,采用摩擦磨损试验仪对熔覆层的摩擦学性能进行研究。结果低激光功率下,熔覆材料上浮流失严重,熔覆层的相成分主要是Ti N,Ti B,Ti B2等硬质相,硬度较高,存在裂纹。高激光功率下,基材的熔化稀释较好地抑制了润滑相h-BN的上浮,减少了溅射损失,发生了包晶反应,生成了单质金属Ti,熔覆层硬度低,但摩擦磨损试验表明,涂层中润滑相h-BN含量的增加使得形成了更好的润滑膜,降低了摩擦系数。结论在输出电流400 A,脉宽5 ms,频率12Hz,扫描速度120 mm/min,搭接率50%~60%的条件下进行激光熔覆,所得熔覆层的表面状态平整,耐摩擦性能最好。
[Abstract]:Objective to optimize the cladding process parameters of laser cladding solid lubricating coating on titanium alloy and improve the wear resistance of titanium alloy surface. Methods Nd:YAG laser was used to prepare h-BN solid self-lubricating coatings on the surface of TC4 titanium alloy at high power and low power respectively. The macroscopic morphology, phase composition, microstructure and hardness of the cladding ceramic coating were observed and analyzed. The tribological properties of the cladding layer were studied by friction and wear tester. Results the floatation loss of cladding material was serious at low laser power. The phase composition of the cladding layer was mainly composed of hard phases such as Ti B B 2 and Ti B 2, and the hardness was high and cracks existed. At high laser power, the melt dilution of the substrate can effectively inhibit the floating of the lubricating phase h-BN, reduce the sputtering loss, produce the peritectic reaction, and form the simple metal Ti.The hardness of the cladding layer is low, but the friction and wear tests show that, With the increase of h-BN content in the lubricating phase, a better lubricating film is formed and the friction coefficient is reduced. Conclusion under the conditions of output current 400 A, pulse width 5 Ms, frequency 12 Hz, scanning speed 120 mm / min, lap ratio 50% and 60%, the surface of the cladding coating is smooth and the friction resistance is the best.
【作者单位】：西北有色金属研究院;
【基金】：陕西省青年自然基金(2015JM5252)~~
【分类号】：TG174.4

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