Aluminum based silicon carbide composite materials have the characteristics of high thermal con-ductivity,low thermal expansion,and good dimensional stability;therefore,the composites are widely used in space microwave component shell products.In order to meet the functional requirements of conductivity,welding,and heat dissipation when applied to antenna microwave components,aluminum based silicon carbide composite materials need to be chemically plated with nickel,which introduces hydrogen,thus requiring research on hydrogen release and control.Here,the hydrogen distribution of nickel plating on aluminum based silicon car-bide has been analyzed,and SEM,XRD and other methods are used to characterize the microstructure of aluminum based silicon carbide substrate and nickel plating layer.There are certain pore structures in both the sub-strate and plating layer,providing a place for hydrogen storage.The experimental method of hydrogen microprinting has been used to characterize the distribution of hydrogen.The results showed that the hydrogen distri-bution pattern in aluminum based silicon carbide nickel plating are as follows:after nickel plating on aluminum based silicon carbide,hydrogen is distributed in the nickel plating layer and the shallow substrate under the coating,and with the extension of time,hydrogen spontaneously diffuses to the deep substrate,and hydrogen is mainly distributed in the Al matrix and less on SiC particles,especially,distributed in micropores and dislocation defects in the substrate and Ni.Herein,TDS has been used to test the hydrogen release of aluminum based silicon carbide nickel plating after hydrogen removal at different temperatures.The results show that hydrogen release is significantly reduced after high temperature hydrogen removal,and high temperature is beneficial obviously for hydrogen release.
随着热塑性复合材料在航空领域的用量日益增加,如何解决结构复杂热塑性航空部件的连接问题引起了研究者的广泛关注.利用其可二次成型的特点可采用焊接,感应焊接是其中一种快捷、可靠的连接方式.感应焊接工艺过程稳定,可实现连续化焊接,是一种人为因素介入较少、小(焊接装置小)、快(焊接速度快)、灵活的焊接技术,也被视为热塑性复合材料连接技术未来最重要的发展方向.本文采用热电偶测温研究了连续碳纤维增强聚苯硫醚(CF/PPS)焊接试样厚度方向上温度分布及温度随时间的变化规律,确定了不同功率下焊接试样可焊的最长时间.采用定点焊接的方式研究了焊接功率及时间对单搭接剪切强度的影响,并探索了不同植入层用于CF/PPS热塑性复合材料感应焊接的可行性.
为某型民用飞机长桁结构设计选型提供参数,研究了复合材料T型长桁截面尺寸、冲击损伤对压缩性能的影响.对四种不同截面构型的复合材料T型长桁进行了压缩试验,得到了不同截面长桁的载荷-应变曲线.对四种不同截面构型的复合材料T型长桁引入了冲击损伤,研究了冲击损伤对不同截面长桁压缩性能的影响.基于ABAQUS软件建立了T型长桁的有限元模型,通过有限元分析方法和试验的对比,对模型进行验证,验证后的模型用于飞机长桁选型设计.
选择聚乙烯醇水溶性纤维(PVAF)作为增强剂,研究了PVAF不同添加量对医疗诊断试纸基纸性能的影响.实验结果表明,医疗诊断试纸基纸的干、湿强度随着PVAF添加量的增加而提高.当PVAF添加量超过7.5%时,基纸的干、湿强度提高趋势变缓,基纸的吸水速度随PVAF添加量的增加而有所下降,但下降幅度较小;当PVAF添加量超过5%时,基纸的吸水速度下降趋势变缓,添加PVAF对基纸的吸水率影响很小.
2 月5 日, 江苏新沂自然资源和规划局发布了晓星碳材料(江苏) 有限公司年产26400 吨碳材料项目建设项目用地预审与选址意见书.韩国晓星集团(中国) 碳纤维公司董事长朴前进表示, 投资徐州, 是集团经过多地考察、深思熟虑后作出的决策, 主要基于徐州得天独厚的区位优势、完备的基础配套, 以及优良的营商环境, 让企业坚信, 随着项目的深入实施, 碳纤维产业一定会迅速做大做强, 晓星集团也一定会在徐州实现跨越式的发展.
