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碳布增强聚芳基乙炔新型防热材料 总被引:9,自引:1,他引:8
本文研究了新型高碳聚芳基乙炔树脂(PAA)的成碳率及其碳布增强防热材料(2DC/PAA)成型工艺,对复合材料的性能进行了表征.结果表明,聚芳基乙炔树脂的成碳率高于酚醛树脂,C/PAA材料烧蚀性能优异,氧-乙炔线烧蚀率0.004mm/s;但材料机械性能较低,剪切强度仅为5.8MPa. 相似文献
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酚醛改性聚芳基乙炔基复合材料探索 总被引:12,自引:0,他引:12
闫联生 《玻璃钢/复合材料》2001,(4):22-24,31
聚芳基乙炔(PAA)树脂具有残碳率高、吸水率低、固化反应为加聚反应、无低分子物副产物逸出等特点,是专为新一代树脂基热防护复合材料而研制的。但其与碳布的浸润性及粘接性能差,碳布增强复合材料的剪切强度较低。本文采用酚醛树脂对PAA树脂进行改性处理,在不降低残碳率的情况下,明显改善了PAA树脂与碳布的粘接性能。改性后碳/聚芳基乙炔复合材料的剪切强度由5.5MPa提高到11MPa以上。 相似文献
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热防护材料的新进展——芳基乙炔共聚物的碳纤维增强材料 总被引:11,自引:2,他引:11
芳基乙共聚物有很高的残碳率,在1000℃高温下残碳率可达85-90%,预聚物在9.7-1.4MPa压力下,于150-200℃固化交联,固化过程中没有小分子物产生。共聚物对碳纤维有较好的粘接力,可以用缠绕、模压工艺制备固体火箭发动机的热防护构件。这是进入90年代以后国内外烧材料和碳/碳复合材料领域中的重大进展。 相似文献
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Ö. Öztürk Cumhur Sipahi Simel Ayyildiz 《Journal of Adhesion Science and Technology》2013,27(10):1026-1038
Purpose: To compare the shear bond strengths of six different porcelain laminate veneer (PLV) materials cemented to enamel with two different MDP-containing resin cements. Materials and methods: Totally 120 disc specimens were fabricated with In-Ceram alumina (ICA), Turkom-CeraTM (TCR), IPS Empress (IPS), IPS Empress-II (IPS2), Finesse (FNS), and Ceramco-3 (CER) ceramic systems (n = 20). Sixty specimens were cemented with self-adhesive resin cement (Clearfil SA), and 60 specimens were cemented with self-etch resin cement (Panavia F2.0) to enamel. Thus, 120 PLV–enamel specimens were assigned to 12 experimental groups (ICA/Pv, ICA/Cf, TCR/Pv, TCR/Cf, IPS/Pv, IPS/Cf, IPS2/Pv, IPS2/Cf, CER/Pv, CER/Cf). Shear force was applied on PLV–enamel interfaces until failure. Obtained data were statistically analyzed with ANOVA and t-tests. Results: Obtained shear bond strength values (SBSV) ranged as follows, respectively; TCR/Cf (7.70 MPa), FNS/Cf (7.57 MPa), TCR/Pv (6.91 MPa), ICA/Pv (5.05 MPa), CER/Pv (4.75 MPa), IPS2/Cf (4.66 MPa), FNS/Pv (4.43 MPa), IPS2/Pv (3.97 MPa), CER/Cf (3.82 MPa), IPS/Pv (3.62 MPa), ICA/Cf (3.59 MPa), IPS/Cf (3.11 MPa). Highest SBSV were obtained in TCR groups (7.70 MPa for TCR/Cf and 6.91 MPa for TCR/Pv) and lowest SBSV were obtained in IPS groups (3.11 MPa for IPS/Cf and 3.62 MPa for IPS/Pv) in both resin cements. No significant bond strength difference was found between two resin cements. Conclusions: TCR groups showed highest SBSV; lowest SBSV were obtained with both IPS PLVs. The resin cement type did not significantly affect the bond strength value of a ceramic type, except for the Finesse system. 相似文献
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围绕常溧线航道升级改造需要,研发了一种固定式复合材料防撞护舷,通过ANSYS/LS-DYNA有限元软件计算了防撞消能效果,采用真空导入工艺实现了工业化制造,通过钢管混凝土定位桩和膨胀螺栓实现了防撞护舷与桥墩之间的连接。结果表明,设置端头防撞护舷后,桥墩受到的最大横桥向船撞力下降38.0%;设置侧面防撞护舷后,桥墩沿横桥向、顺桥向方向受到的最大船撞力分别削减了41.8%、29.3%。复合材料防撞护舷性能优异,能大幅削减船撞力,有效保护桥梁结构安全,适应航道升级改造的需要,为内河航道桥梁的防撞保护提供了新的思路。 相似文献
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纳米SiO_2改性环氧树脂胶粘剂的研究 总被引:3,自引:1,他引:2
选择纳米 SiO_2 作为增强材料改性环氧树脂基体, 以物理分散法将纳米 SiO_2 分散在环氧树脂中。通过力学性能测试和热稳定性能测试, 研究了不同含量的纳米 SiO_2 对改性环氧树脂胶粘剂的热性能、拉伸性能和冲击性能的影响; 通过 NOL环测试和扫描电子显微镜(SEM) 分析, 研究了不同含量的纳米 SiO_2 对国产芳纶纤维/改性环氧复合材料的界面性能和层间剪切强度的影响。实验结果表明, 基体树脂中当 w( 纳米SiO_2)=3%时, 改性环氧树脂胶粘剂的拉伸强度和冲击强度分别提高了 28.8%和 22.6%, 复合材料的层间剪切强度(ILSS) 达到最大值, 比未改性胶粘剂提高约 56.8%。 相似文献