Vacuum brazing of alumina to stainless steel using femtosecond laser patterned periodic surface structure
Vacuum brazing of alumina to stainless steel using femtosecond laser patterned periodic surface structure
复制标题
使用飞秒激光图案化周期性表面结构将氧化铝真空钎焊至不锈钢
DOI：
10.1016/j.msea.2016.03.068
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发表时间：
2016-04-26
期刊：
影响因子：
6.4
通讯作者：
Zhou, Y. N.
中科院分区：
文献类型：
--
作者：
Zhang, Y.;Zou, G.;Zhou, Y. N.
陶瓷表面图案化由于不需要复杂的多层夹层，且成本低，是一种很有前途的降低陶瓷-金属接头残余应力的方法。然而，文献表明，先前检测的陶瓷-金属钎焊的表面图案在毫米尺度上，这限制了应用和增强程度。本研究采用飞秒激光烧蚀技术在陶瓷表面制备微尺度的周期性表面图案（凹槽）。烧蚀过程中未产生任何缺陷或损伤。通过控制烧蚀参数，实现了槽形尺寸的可调。采用工业用AgCuTi钎料对带有表面凹槽的Al2O3陶瓷进行了304不锈钢的高温真空钎焊。合理设计表面槽后，接头的平均强度为66 MPa，是平界面接头强度的2.75倍。有限元分析模型结合断裂路径检验表明，周期性表面图案引起的残余应力重分布是接头强度增强的主要原因。(C) 2016 Elsevier B.V.版权所有
Ceramic surface patterning is a promising method to reduce the residual stress of ceramic-metal joints, since it needs no complex multiple interlayer and is cost effective. However, literature shows that surface patterns previously examined for ceramic-metal brazing were at a millimeter scale, which limits the application and the degree of enhancement. In this study, femtosecond laser ablation was used to fabricate microscale periodic surface patterns (grooves) on ceramic surfaces. No defects or damage were induced during the ablation. The groove dimension was tunable by controlling ablation parameters. High temperature vacuum brazing of 304 stainless steel to the Al2O3 ceramic with surface grooves was performed using a commercial AgCuTi brazing filler metal. With properly designed surface grooves, the average joint strength was 66 MPa, 2.75 times of that of the flat-interface joints. Finite Element Analysis models combined with fracture path examination indicated that the redistribution of residual stress induced by periodic surface pattern accounted for the joint strength enhancement. (C) 2016 Elsevier B.V. All rights reserved.