目的：在NiCr20 TiAl基体材料上进行镍基纳米TiN电沉积复合镀后再开展激光重熔工艺,研究激光重熔参数对镀层表面质量、结合力及硬度的影响。方法采用正交实验,研究不同激光重熔参数(扫描速率、搭接量、离焦量等)对重熔镀层的影响,采用显微硬度计、扫描电镜和划痕仪进行硬度、表面形貌和结合力检测,以得到较优工艺参数。结果通过控制重熔参数对镀层表面能量和表面形貌的影响,以降低表面性能差异,以得到了激光重熔较佳工艺参数为：电流115 A,脉宽为8 ms,频率为10 Hz,离焦量15 mm,扫描速度230 mm/min,使获得的镀层表面形貌比较平整,结合力提高到大于60 N,硬度值平均为632HV,并且硬度分布均匀。结论激光重熔工艺可消除纳米复合电沉积过程中产生的间隙,纳米复合镀层致密均匀,镀层与基体之间产生良好的冶金结合,镀层表面硬度分布均匀,力学性能趋近一致。
ABSTRACT:Objective Nickel-based nano TiN composite deposition coatings were remelted by laser process. The effects of laser remelting parameters on the surface quality, binding force and hardness of the coatings were researched. Methods Orthogonal ex-periments were used to study the effects of different laser remelting parameters ( scan rate, amout of overlap, defocus amount,etc) on the remelted coating, and the hardness, surface morphology and binding force were tested by using microhardness meter, SEM and scratch tester, in order to obtain optimal process parameters. Results By controlling the effects of remelting parameters on the coating surface energy and surface morphology in order to reduce the differences in surface properties, preferable laser remelting process parameters were obtained:electric current 115 A, pulse width 8 ms, frequency 10 Hz, defocus amount 15 mm, and scan-ning speed 230 mm/min. Under this condition, smooth surface morphology was obtained, with the binding force improved to 60 N, the average hardness value reaching 632HV, and the hardness distribution was uniform. Conclusion Laser remelting process could eliminate the gap produced by nano composite deposition, and the nano composite coating became compact and uniform. A good metallurgical bond could be formed between the coating and the substrate, the hardness distribution was uniform on the coating sur-face and the mechanical properties tended to be consistent.
参考文献
| [1] | 陈光霞.金属零件激光表面熔覆强化实验研究[J].机械研究与应用,2014(02):74-75,78. |
| [2] | 涂伟毅;徐滨士;董世运.复合电沉积机理现状及对纳米复合电刷镀机理研究的启示[J].中国表面工程,2003(4):1-6. |
| [3] | 袁庆龙;凌文丹.镍基纳米复合镀层的研究进展[J].电镀与环保,2012(3):1-4. |
| [4] | 封存利;杜鑫磊;袁庆龙.纳米颗粒增强型复合镀层的研究现状与展望[J].材料保护,2014(4):48-50,59. |
| [5] | 贺长林;陈少克;周中河.激光熔覆工艺对镍基碳化钛熔覆层组织的影响[J].金属热处理,2014(7):111-115,116. |
| [6] | 王东生;田宗军;沈理达;黄因慧.激光熔覆技术研究现状及其发展[J].应用激光,2012(6):538-544. |
| [7] | 李养良;金海霞;白小波;席守谋.激光熔覆技术的研究现状与发展趋势[J].热处理技术与装备,2009(4):1-5. |
| [8] | Telasang, Gururaj;Majumdar, Jyotsna Dutta;Wasekar, Nitin;Padmanabham, G.;Manna, Indranil.Microstructure and Mechanical Properties of Laser Clad and Post-cladding Tempered AISI H13 Tool Steel[J].Metallurgical and Materials Transactions, A. Physical Metallurgy and Materials Science,20155(5):2309-2321. |
| [9] | LIU ShuNv;LIU ZongDe;WANG Yang;YUE Peng.Ti-based composite coatings with gradient TiCx reinforcements on TC4 titanium alloy prepared by laser cladding[J].中国科学:技术科学（英文版）,2014(7):1454-1461. |
| [10] | 郑子云;马冰;依颖辉;郭昌明;冯胜强;刘光;潘力平.激光熔覆再制造镍基高温合金气门的组织和性能研究[J].兵器材料科学与工程,2013(3):101-104. |
| [11] | 袁庆龙;冯旭东;曹晶晶;苏志俊.激光熔覆技术研究进展[J].材料导报,2010(3):112-116. |
| [12] | 张坚;吴文妮;赵龙志.激光熔覆研究现状及发展趋势[J].热加工工艺,2013(6):131-134,139. |
| [13] | 赵兵;路远航;李章;骆芳.低碳钢表面激光熔覆Ni60合金的工艺及性能[J].金属热处理,2014(7):124-129. |
| [14] | 吴建峰;符轲;续晓霄;戴姣燕;徐金富.工艺参数对激光熔覆层结构的影响[J].兵器材料科学与工程,2014(03):106-109. |
| [15] | 刘建刚;秦茶;段松.45钢激光熔覆镍基合金组织及性能研究[J].河北冶金,2013(12):16-21. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%