王顺花
,
尚伦霖
,
张广安
,
耿中荣
,
刘千喜
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2014.06.005
采用闭合场非平衡直流磁控溅射技术和阴极电弧离子镀技术在轴承钢表面分别制备了DLC和CrN薄膜,在全配方发动机油(CF-4,15W/40)润滑条件下,选择DLC/钢、CrN/钢摩擦配副,用SRV-Ⅳ摩擦实验机考察了25℃和100℃时DLC与CrN薄膜在不同载荷下的摩擦因数和磨损率,并对摩擦界面进行分析.结果表明:DLC和CrN薄膜在油润滑条件下的摩擦因数都随着载荷的增加而降低;DLC和CF-4构成的固液复合润滑体系具有更加优异的摩擦学性能;活性较高的CrN薄膜与发动机油中的添加剂相互作用,在摩擦界面上发生摩擦化学反应形成摩擦化学反应膜,并且薄膜表面形成的氧化层有利于提高薄膜在高温时的耐磨性.
关键词:
DLC薄膜
,
CrN薄膜
,
摩擦因数
,
磨损率
,
摩擦学性能
,
固液复合润滑
,
摩擦化学反应
N. Afsar Kazerooni
材料科学技术(英文)
A plasma electrolytic nitrocarburising (PEN/C) process was performed on stainless steel 316L to improve the surface properties for using as medical implants. A bath was optimised to reduce the required voltage to 150 volts. Aqueous urea-based solutions with 10% NH4Cl were prepared with slightly different amounts of Na2CO3 to optimise the electrolyte composition. The surface and the cross-section morphologies were studied by scanning electron microscopy. The microstructure and the chemical composition of samples were investigated by X-ray diffraction (XRD) and energy dispersive X-ray (EDX) techniques. The microstructure of the outer layer of the coatings was found to be a complex oxide containing Cr and Fe. The wear properties
of the samples were examined by using a pin on disk wear test with Ringer0s solution and were compared with their wear properties in the ambient atmosphere. The Ringer0s solution acted as a lubricant, reducing friction coe±cient. Hardness and roughness were also studied. The bath with the composition of 10% NH4Cl and 3% Na2CO3 exhibited the best tribological properties. The results showed that the tribological properties of treated samples were improved and the wear mechanism was abrasion of the pin.
关键词:
Plasma electrolytic nitrocarburising
Zhong HAN
,
Yusheng ZHANG
材料科学技术(英文)
Nanostructured (ns) materials, i.e., polycrystalline materials with grain sizes in the nanometer regime (typically below 100 nm), have drawn considerable attention in the past decades due to their unique properties such as high strength and hardness. Wear resistance of ns materials, one of the most important properties for engineering materials, has been extensively investigated in the past decades. Obvious differences have been identified in friction and wear behaviors between the ns materials and their corresponding coarse-grained (cg) counterparts, consistently correlating with their unique structure characteristics and mechanical properties. On the other hand, the superior tribological properties of ns materials illustrate their potential applications under contact loads. The present overview will summarize the important progresses achieved on friction and wear behaviors of ns metallic materials, including ultrafine-grained (ufg) materials in recent years. Tribological properties and effects on friction and wear behaviors of ns materials will be discussed under different wear conditions including abrasive wear, sliding wear, and fretting wear. Their correlations with mechanical properties will be analyzed. Perspectives on development of this field will be highlighted as well.
关键词:
Nanostructured metals
,
metals
,
Friction
,
Wear
,
Mech
Yaxu JIN
材料科学技术(英文)
Nickel-phosphorus (Ni-P) composite coatings containing potassium titanate (K2Ti6O13) whiskers (PTWs) were prepared by electroless plating. The surface morphology and component of coatings were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), respectively before and after wear test. The tribological performance was evaluated using a pin-on-disk wear tester under dry conditions. It is found that the Ni-P-PTWs composite coatings exhibit higher wear resistance than Ni-P and Ni-P-SiC electroless coatings. The favorable effects of PTWs on the tribological properties of the composite coatings are attributed to the super-strong mechanical properties and the specific tunneling structures of PTWs. The PTWs greatly reinforce the structure of the Ni-P-based composite coatings and thereby greatly reduce the adhesive and plough wear of Ni-P-PTWs composite coatings.
关键词:
Potassium titanate whiskers
,
化学镀
,
复合镀层
,
摩擦学性能
霍丽霞
,
周晖
,
桑瑞鹏
,
张凯锋
,
蒋钊
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2015.01.013
对钛合金表面的PI/MoS2涂层进行了湿热老化试验,在70℃、98% RH条件下存储长达27 d.采用衰减全反射红外光谱和透射红外光谱分别对涂层表面及涂层进行分析测试,利用X射线光电子能谱对涂层表面成分进行分析.通过球盘摩擦试验机考察了湿热老化对润滑涂层的真空及大气摩擦性能的影响.采用拉脱法测试了湿热老化前后涂层附着力.结果表明,湿热会导致PL/MoS2润滑涂层表面的胶黏剂聚酰亚胺被水解侵蚀,膜层表面深度在50 nm以内的部分MoS2被氧化.湿热试验前后涂层的真空耐磨寿命降低13%,大气耐磨寿命降低16%;真空摩擦因数略有增加且波动增大,而大气摩擦因数显著增加,涂层附着强度也略显降低.
关键词:
湿热老化
,
聚酰亚胺
,
润滑涂层
,
摩擦学性能
,
红外光谱
李专
,
肖鹏
,
熊翔
,
黄伯云
新型炭材料
doi:10.1016/S1872-5805(09)60029-9
以针刺炭纤维整体毡为预制体, 联用化学气相沉积法与熔融渗硅法制得炭纤维增强C/SiC双基体(C/C-SiC)复合材料; 研究了C/C-Si材料的显微结构、力学性能和不同制动速度下的摩擦磨损性能及机理.结果表明: C/C-SiC材料具有适中的纤维/基体界面结合强度, 弯曲强度和压缩强度分别达240MPa和210MPa, 具有摩擦系数高(0.41~0.54), 磨损小(0.02cm3/MJ), 摩擦性能稳定等特点. 随着制动速度提高, C/C-Si材料的摩擦磨损机制也随之变化: 在低速制动条件下主要表现为磨粒磨损; 中速时以黏着磨损为主; 高速时以疲劳磨损和氧化磨损为主.
关键词:
C/SiC复合材料
,
摩擦磨损性能
,
制动材料
,
化学气相沉积法
,
熔融渗硅
王顺花
,
马新莉
,
郝耕
宇航材料工艺
doi:10.3969/j.issn.1007-2330.2016.06.015
采用非平衡磁控溅射技术在304L不锈钢和单晶硅基底上沉积WC/C多层复合涂层,利用扫描电镜、Raman光谱仪、X射线衍射仪等研究WC/C复合涂层的微观结构,采用纳米压痕仪、划痕测试系统测试涂层的力学性能,利用电化学测试系统和摩擦磨损试验机分别研究涂层在人工配置的海水环境的耐蚀性能和摩擦性能.结果表明:WC/C复合涂层内含有较多类石墨sp2键结构,存在WC1-x相并镶嵌在非晶碳基质中.较之于304L不锈钢基底,WC/C复合涂层在海水环境中表现出更好的耐蚀性与更优异的摩擦适应性.
关键词:
WC/C复合涂层
,
微观结构
,
海水环境
,
耐蚀性
,
摩擦性能
卢雪峰
,
肖鹏
新型炭材料
采用催化化学气相法在炭纤维表面原位生长纳米炭纤维后,再通过化学气相渗透法制备出纳米炭纤维改性C/C复合材料.采用微动摩擦磨损试验考察纳米炭纤维改性C/C复合材料的摩擦磨损性能,探讨原位生长纳米炭纤维对C/C复合材料摩擦磨损机理.结果表明,采用纳米炭纤维改性后C/C复合材料的摩擦过程更平稳,磨损量减小.纳米炭纤维与热解炭形成复合基体,这种复合基体在摩擦过程中形成高强度高模量的摩擦膜,从而影响复合材料的摩擦性能.
关键词:
C/C复合材料
,
纳米炭纤维
,
摩擦性能