C/C复材与高温合金异种材料蜂窝结构钎焊界面组织及力学性能

Microstructure and Mechanical Properties of Brazing Interface Between C/C Composite and Superalloy Dissimilar Material Honeycomb Structure

在钎焊温度为1040℃,保温时间为15 min的条件下,采用BNi-2钎料钎焊连接C/C复合材料面板和GH3536高温合金异种材料蜂窝结构,研究了不同钎料层厚度对板–芯界面微观组织变化和板–芯拉脱性能影响。结果表明,焊后板–芯接头由钎料与C/C母材反应区、钎料与蜂窝反应区和钎料凝固区3个区域组成,钎料与C/C母材反应生成了Cr_(3)C_(2)反应层,钎料与蜂窝反应区内生成了Si的金属间化合物和Cr_(3)C_(2)颗粒。随着钎料厚度的增加,接头拉脱性能先升高后降低,当钎料厚度为0.12 mm时,板–芯接头拉脱强度达到最高9.69 MPa,断裂位置主要发生在C/C基体内。

BNi-2 braze was used to brazing C/C composite panel and GH3536 superalloy honeycomb under the brazing parameter at brazing temperature of 1040℃and holding time 15 min.The influence of the thickness of brazing braze on the microstructure and flatwise tensile strength of C/C composite and superalloy honeycomb sandwich structure was analyzed.Results show that the panel-honeycomb interface can be divided into reaction zone between C/C composite and braze,reaction zone between braze and honeycomb and braze solidification zone.Cr_(3)C_(2) reaction layer is formed between braze and C/C composite.Intermetallic compounds of Si are formed within the reaction zone between braze and honeycomb.With the increase of thickness braze,flatwise tensile strength increases first and then decreases.When the braze thickness is 0.12 mm,flatwise tensile strength reaches the maximum level at 9.69 MPa.The fracture site mainly occurs in the C/C composite base material.