等离子体表面处理对碳纤维增强树脂基复合材料(CFRP)胶接性能及表面特性的影响EI北大核心CSCD

为改善碳纤维增强树脂基复合材料(CFRP)表面润湿性能及表面活性,提高其胶接强度,采用旋喷式空气等离子体处理设备对CFRP进行表面处理,通过拉伸试验探究等离子体表面处理距离、处理速度对CFRP胶接性能的影响,并利用接触角测量仪、原子力显微镜(AFM)、X射线光电子能谱分析仪(XPS)等测试技术,探究等离子体处理对CFRP表面润湿性、表面形貌、表面化学组分等表面特性的影响。结果表明:CFRP表面经等离子体处理后,胶接强度逐渐提高,处理距离h为10mm,处理速度v为2mm/s时,接头强度最大。接头破坏模式从界面破坏转变为混合破坏模式。随等离子体处理距离及速度的降低,复合材料表面水接触角降低,表面自由能及极性分量增加,表面润湿性及吸附性能提高。经等离子体处理后,CFRP表面产生微米级沟壑,表面积增加,但当处理距离较近时,部分表面树脂因等离子体热响应产生损伤,不利于胶接性能的进一步提升。复合材料基体与等离子体中活性粒子相互作用后,表面含氧基团增多,并产生C—O/C—O、C=O/O—C=O等较为活泼的含氧基团,有利于复合材料与胶粘剂形成牢固的化学键合。等离子体处理可以显著提高复合材料表面润湿性、表面活性及胶接性能。     

冷等离子体射流中微细电火花加工特性研究

采用晶体管脉冲电源,在氧气辅助氮气等离子体射流、氮氧混合等离子体射流及外部压缩空气辅助氮气等离子体射流等不同冷等离子体介质中进行了微细电火花加工特性的实验研究,以期确定加工过程稳定的工艺条件,达到提高加工效率和加工质量的目的。在氧气辅助氮气等离子体射流实验中发现,随着氧气流量的增加,材料去除速度和表面粗糙度值均有增大趋势;采用压缩空气辅助氮气等离子体射流的电火花加工在表面质量、边缘质量方面均优于氧气辅助氮气等离子体射流加工。     

低温空气等离子体处理对铝合金表面粘接性能的影响

为了提高铝合金与高分子材料之间粘接强度,采用低温空气等离子体预处理技术,对5083型铝合金表面进行活化处理。对铝合金表面的显微形貌、接触角、表面能、化学元素的成分及价态等理化性能进行了分析,对铝合金与环氧树脂的粘接性能进行了测试。结果表明:低温等离子体处理后铝合金表面的活性显著增加,水接触角由88.7°最低降至10.1°,表面能由19.21 mJ/m~2增加到74.04 mJ/m~2,表面氧元素含量明显增加,显微形貌及粗糙度未发生明显改变。铝合金板粘接后的拉剪强度随处理时间增加而增加,最高值达到12.4 MPa,较处理前提高了约4倍,表面氧元素的含量及活性增加是树脂与铝合金粘接性能提升的重要因素。     

冷等离子体处理工艺对丁腈橡胶表面性能的影响

目的采用冷等离子体处理工艺(CPT)改善丁腈橡胶(NBR5080)的表面润湿性。方法采用Ar、空气和O2等3种气氛,通过调整工艺参数对NBR5080进行表面处理,测试NBR5080的静态接触角、计算表面能;用扫描电子显微镜(SEM)及原子力显微镜(AFM)观察表面形貌;X射线光电子能谱(XPS)测试分析表面的化学元素。结果 3种气氛处理后,NBR5080的静态接触角由91°分别降到25°,27°,35°,表面粗糙度由16.37 nm分别提高到97.78,75.12,59.58 nm;与聚四氟乙烯薄膜之间由不能粘接到剥离强度分别提高到44.2,40.6,32.3 N/m。结论 3种处理气氛均能改善NBR5080的表面润湿性,其中Ar气氛的处理效果最佳,处理工艺参数为功率100 W、时间600 s、压强30 Pa;处理后的NBR5080与PTFE的粘接性能明显提高;处理后NBR5080的表面润湿性变化存在时效性。     

开放式低温等离子体对树脂基复合材料表面处理性能研究

目的 采用开放式低温等离子体对树脂基复合材料表面处理,研究其对树脂基复合材料粘接性能的影响。方法 运用响应曲面法,对开放式低温等离子体加工工艺与树脂基复合材料表面自由能交互性进行研究。采用接触角测量仪、扫描电子显微镜(SEM)、三维形貌仪、X射线光电子能谱仪(XPS)、傅里叶红外光谱仪(FT-IR)等仪器对开放式低温等离子体处理前后复合材料的接触角与表面能、表面微观形貌与表面粗糙度、表面化学成分进行分析,使用万能试验机对处理前后复合材料的粘接强度进行研究。结果 输入功率、喷枪距离与试样移动速度3个响应因子中,喷枪距离对试样表面能的影响最为显著,其次是试样移动速度与输入功率。当开放式低温等离子体加工工艺为P=800 W,d=11.8 mm,v=10 mm/s时,表面能最大,从24.8 mJ/m²增加到78.3 mJ/m²,表面粗糙度与未处理试样相比提高了约2.5倍。处理后试样表面的氧元素含量明显增加,氧元素主要以含氧官能团的形式存在,材料表面极性增加。开放式低温等离子体对树脂基复合材料处理后,粘接试样平均拉伸剪切强度从16.6 MPa增加到27.5 MPa,粘接强度提高了约65.7%,粘接接头破坏形式从界面破坏到材料基材破坏。结论 开放式低温等离子体对树脂基复合材料表面处理后,能够有效地增加其粘接强度,树脂基复合材料润湿性与表面能、表面粗糙度以及表面含氧官能团数量增加,是粘接强度提高的主要因素。     

大气压氧等离子体净化溶胶-凝胶TiO_2膜的研究（英文）

用溶胶-凝胶法制备了TiO_2薄膜,对经针状电极预电离产生的非平衡大气压氧等离子体射流净化该TiO_2膜进行了研究。用水接触角、表面形貌和X射线光电子能谱检测了氧等离子体与薄膜的相互作用。在氧等离子体和薄膜相互作用2 min后,经XPS观察到新的Sn3d与Nl s峰,但没有Ti3p信号,这说明经2min等离子体处理后,50nm厚的TiO_2薄膜已被除去。而涂有油和硬脂酸污染物的膜,经1min等离子体处理后,Ols和Ti3p信号没有改变。水接触角的减少和表面形貌的光滑可视为污染物的去除。从大气压氧等离子体中激发态氧能有效地除去污染物,证明这是清洗TiO_2膜上污染物的新途径。     

聚四氟乙烯射频等离子体表面改性研究

采用氧等离子体对PTFE粘接件进行处理,测试了压剪粘接件和拉伸粘接件的粘接强度,分析了氧等离子体处理前后PTFE的接触角变化情况,同时,采用了AFM对PTFE进行了表面形貌的观察.     

等离子体处理对CFRP筒状件内壁活化效果的影响∗

为解决碳纤维增强树脂基复合材料（CFRP）筒状件内壁表面化学惰性较高导致与金属涂层结合强度差的问题，采用射频辉光放电对其内表面进行活化处理来提高其表面活性。通过接触角测试和红外光谱分析，探究等离子体处理气压、射频电源功率、处理时间和离子种类对活化效果的影响。结果表明，经射频辉光放电等离子体处理后 CFRP 筒状件内壁表面等离子体活化效果明显，表面能显著提高。其他工艺参数相同情况下，活化效果随气压增大先提升后降低，随射频电源功率和处理时间的增大而提高，以氧等离子体活化效果最佳。其中，在处理气压 0.5 Pa、射频电源功率 500 W、处理时间 60 min、氧等离子体条件下效果最为显著，水和二碘甲烷的接触角分别由 71.29°、49.36°降低到 4.93°、5.39°，表面能从 38.85 mJ·m^?2 提升到 74.73 mJ·m^?2 。通过红外光谱分析，经等离子体处理后的 CFRP 中 C-H 和 C≡C 等非活性键被打断，带有 C=O 的醛基和羧基活性基团增多，浸润性大幅提高。活化后的 CFRP 基体与金属薄膜的膜基结合力由不足 0.1 MPa 提升至 0.49 MPa。研究通过射频辉光放电对 CFRP 筒状件内壁表面进行活化处理，为制备高结合强度的金属涂层打下基础。     

硬质聚氨酯泡沫塑料表面等离子体改性研究

测试了三种泡沫塑料表面（含脱模剂但经等离子体处理、含脱模剂不经等离子体处理和不含脱模剂不经等离子体处理）与涂层之间的结合力,采用XPS表面分析手段分析了涂层附着力提高的原因。     

大气压冷等离子体射流辅助微铣削纯钛试验研究

纯钛具有良好的机械性能和较高的应用价值,但其塑性高、导热性差的特点导致切削加工时存在切削力较大、表面质量较差等问题。为提高金属零部件微铣削加工质量,一些辅助加工手段被提出,但未能改变材料特性、未能解决冷却介质浸润性差和材料塑性高的问题,且改善材料表面质量的效果有限。大气压冷等离子体射流可在短时间内将材料表面改性为超亲水状态且可降低材料强度、促进材料断裂,故提出将大气压冷等离子体射流引入纯钛材料的微铣削过程,并在研究冷等离子体射流辅助加工机理的基础上,于不同冷却润滑环境下开展微铣削纯钛试验。结果表明:冷等离子体射流通过改善冷却介质浸润性、促进材料断裂,可有效提高加工表面质量、缓解刀具磨损,从而显著改善纯钛的切削加工性能。     

常压空气等离子处理对铝合金胶接接头强度的影响

为改善铝合金表面润湿性与胶接强度,采用常压空气射流等离子体对5052铝合金进行表面处理。通过接触角测试,表面自由能计算和胶接接头剪切强度测试表明处理时间对铝合金表面改性效果影响不大,随着处理距离减短,铝合金表面自由能、胶接接头强度均逐步提升。处理距离为5 mm时等离子处理铝合金获得最佳表面改性效果,铝合金胶接接头剪切强度由10.6 MPa提升至19.3 MPa,失效模式由界面失效转变为内聚失效。利用SEM,XPS,傅立叶变换红外光谱等检测手段分析不同处理距离对应表面理化特性的变化,结果表明:处理距离较远时,等离子体并未改变铝合金表面物理形貌,其主要改性效果体现为表面清洗;处理距离较近时,铝合金表面高温熔融产生复杂微结构的粗糙氧化层,同时氧化层表面吸附羟基等极性官能团,显著提升了其表面自由能与胶接强度。     

Surface modification of high performance PBO fibers using radio frequency argon plasma

The radio frequency argon plasma was applied to improve surface properties of the PBO fiber. The fiber tensile strength was measured, and the surface chemical components, topography and wettability were analyzed by X-ray photoelectron spectroscopy (XPS), atomic force microscopy and dynamic contact angle analysis (DCAA), respectively. Results suggested that over 90% of the fiber tensile strength was reserved after treatment at lower power levels. The surface oxygen atoms increased with a very small extent and the O/C ratio increased from 0.25 to 0.29. The plasma sputtering caused scission of chemical bonds and damage to the surface crystallizing layers, and thus created many active functional groups and roughened surface. However, at high power conditions the more effective ablation and sputtering effects dramatically reduced the tensile strength, surface oxygen contents and roughness. The fiber surface wettability was markedly increased as a result of the functionalization and roughening effects, but the calculated polar and dispersive free energy did not agree well with the measured surface chemical components due to the different effective depths of the surface layers analyzed by DCAA and XPS. The increased roughness was considered to be another reason. The treated fiber exhibited better adhesion with bismaleimide resin, but the maximum interlaminar shear strength of the PBO/bismaleimide composite could not be reproduced by increasing the treatment time at lower power level conditions.     

Evaluation of surface and bonding properties of cold rolled steel sheet pretreated by Ar/O2 atmospheric pressure plasma at room temperature

In this study, cold rolled steel sheet for automotive was pretreated by the Ar/O₂ atmospheric pressure plasma at room temperature to improve the adhesive bonding properties. Through the analysis of contact angle and calculation of work of adhesion, the change of surface properties related to the plasma power, treatment time, and flow rate of O₂ gas were investigated before and after plasma treatment. Contact angle was degreased and work of adhesion was increased after plasma treatment. Meanwhile, the changes of surface roughness and morphology were observed by atomic force microscopy (AFM). And the chemical compositions of the steel sheet before and after plasma treatment were characterized by X-ray photoelectron spectroscopy (XPS). Surface roughness was slightly changed and new functional group, oxides, appeared on the surface of steel sheet after plasma treatment. Based on design of experiments and artificial neural network (ANN), the single lap shear test was performed to analyze the effect of plasma treatment parameters gas on adhesive bonding strength. From the result of the single lap shear test, the adhesive bonding strength of joint which was treated by Ar/O₂ atmospheric pressure plasma was improved about 23% compared with that of untreated sheet.     

Physico-chemical characteristics of high performance polymer modified by low and atmospheric pressure plasma

In this work, the effect of low pressure plasma and atmospheric-pressure plasma treatment on surface properties and adhesion characteristics of high performance polymer, Polyether Ether Ketone (PEEK) are investigated in terms of Fourier Transform Infrared Spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Atomic Force Microscopy (AFM). The experimental results show that the PEEK surface treated by atmospheric pressure plasma lead to an increase in the polar component of the surface energy, resulting in improving the adhesion characteristics of the PEEK/Epoxy adhesive system. Also, the roughness of the treated surfaces is largely increased as confirmed by AFM observation. These results can be explained by the fact that the atmospheric pressure plasma treatment of PEEK surface yields several oxygen functionalities on hydrophobic surface, which play an important role in increasing the surface polarity, wettability, and the adhesion characteristics of the PEEK/Epoxy adhesive system.     

Penetration depth of atmospheric pressure plasma surface modification into multiple layers of polyester fabrics

Penetration depth of plasma surface modification of polyester fabrics was investigated. An eight-layer stack of woven polyester fabrics was exposed to a helium/oxygen atmospheric pressure plasma jet. Water-absorption time was used to evaluate surface hydrophilicity on the top and the bottom sides of each fabric layer and water capillary rise height was recorded as a measure of modification effectiveness for each fabric layer. Surface morphology and chemical compositions of each fabric layer in the stack were analyzed by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). After atmospheric pressure plasma jet treatment, the top side of the polyester fabric became more hydrophilic. The penetration of plasma surface modification into the fabric layers was deeper for fabrics with larger average pore sizes. It was found that helium/oxygen atmospheric pressure plasma jet was able to penetrate 8 layers of polyester fabrics with pore sizes of 200 μm.     

Influence of aging behavior of Armos fiber after oxygen plasma treatment on its composite interfacial properties

This work concerns the aging behavior of Armos fiber and Armos fiber reinforced poly (phthalazinone ether sulfone ketone) (PPESK) composite after oxygen plasma treatment. Armos fiber surface chemical composition, surface morphology and roughness, and surface wettability as a function of storage time in air after oxygen plasma treatment were measured by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and dynamic contact angle analysis (DCAA) system, respectively. The fiber surface aging behavior could be detected obviously in chemical composition and surface wettability, whereas the surface morphology and roughness remained nearly stable after storing in air as long as 10 days after oxygen plasma treatment. The effects of surface aging behavior after oxygen plasma treatment on Armos fiber reinforced PPESK composite interfacial properties were evaluated by interlaminar shear strength (ILSS) test and humid resistance measurement. It was found that the values of ILSS reduced and the composite humid resistance properties decayed. The polar functional groups that were reoriented from the surface into the bulk of the fibers or moved away from the fiber surfaces, maybe responsible for the weak interfacial strength between the fiber and the matrix in composite system.     

表面形貌对TB8钛合金/环氧树脂粘结性能的影响

目的 通过在基体表面构建出不同的微观结构,提升环氧树脂与钛合金的粘结强度。方法 采用等离子刻蚀设备,调节气体流量、处理时间、RF功率对TB8钛合金样品进行处理,并对处理过的样品进行单搭接接头制备。利用扫描电子显微镜对等离子刻蚀前后的样品表面形貌进行研究,利用XPS分析刻蚀前后样品表面化学成分变化,利用水接触角表征样品表面润湿性,利用电子万能试验机对等离子刻蚀处理后的样品与环氧树脂的粘结强度进行研究。结果 采用CF4对样品进行等离子化学刻蚀,不同的刻蚀时间形成了不同类型的表面微观结构,其中圆粒状结构比蜂窝坑结构表面的粘结性能优越。采用Ar对样品进行等离子溅射刻蚀,样品表面形成纳米级片状微坑结构。等离子刻蚀后,基体表面更加洁净,活性增强,水接触角基本降为0°,润湿性显著提升。等离子刻蚀处理前,样品与环氧树脂的粘结强度为5.32MPa;等离子刻蚀处理后,样品与环氧树脂的粘结强度可达23.25 MPa,而经喷砂后,等离子刻蚀处理的样品与环氧树脂的粘结强度高达30.29 MPa。最佳等离子刻蚀处理工艺参数为RF功率540 W,气体流量120 mL/min,处理时间50 min,喷砂后最佳等离子刻...     

Aging of surface properties of ultra high modulus polyethylene fibers treated with He/O2 atmospheric pressure plasma jet

To investigate the relationship between aging of the treatment effect and the gas composition of atmospheric pressure plasma treatment, ultra high modulus polyethylene (UHMPE) fibers were selected as a model fiber to study the aging behavior of fiber surface treated by atmospheric pressure plasma jet (APPJ) with pure helium, helium + 1% oxygen, and helium + 2% oxygen. Atomic force microscopy showed increased surface roughness, while X-ray photoelectron spectroscopy revealed increased oxygen contents after the plasma treatments. The plasma treated fibers had lower contact angles and higher interfacial shear strengths to epoxy than those of the control fiber. Adding 1% of O₂ to helium increased effectiveness of the plasma in polymer surface modification and suppressed aging after the treatment, while adding 2% of O₂ had a negative effect on the APPJ modification results and accelerated aging. In addition, no significant difference in single fiber tensile strength was observed between the control and the plasma treated fibers.