Cl^—致脆对不锈钢磨蚀的影响及其判据研究

测定了ＡＩＳＩ３０４不锈钢在不同Ｃｌ＾－浓度的１ｍｏｌ／ＬＨ２ＳＯ４溶液中的静态腐蚀率及腐蚀损率。同时利用单摆冲击划痕实验机测定了不同条件下材料表面划痕的长度随冲击能耗的变化及其比能耗值,证明了随Ｃｌ＾－浓度的增加,材料表面的比能耗下降,即腐蚀及腐蚀磨损作用加剧原因系材料的表面变脆。     

鞍钢B级钢帘线盘条轧制工艺研究

根据钢帘线盘条对脱碳、氧化铁皮、金相组织、力学性能和表面质量的要求,制定了鞍钢B级钢帘线盘条轧制工艺,通过提高加热钢坯温度的控制精度,优化吐丝温度、吐丝圈径、辊道速度及佳灵装置开口度,减少在轧制、集卷、打包、装卸、堆放和运输等环节的表面划伤,生产出符合技术标准要求的B级钢帘线盘条,满足了用户需求。     

钨合金超声辅助划擦试验及仿真研究

目的 揭示钨合金在超声辅助磨削加工下的材料去除行为。方法 通过超声辅助划擦试验与有限元仿真相结合的方式,分析超声振动作用对材料表面形貌、截面轮廓、划擦力、温度、塑性应变及应变率的影响,探究超声振动作用下的材料去除和表面创成机理。结果 钨合金在划擦过程中发生严重的塑性变形,在划痕两侧出现由耕犁作用而形成的隆起现象。超声辅助划擦形成的划痕表面鳞刺更少且未出现犁沟现象,且划痕深度相较于普通划擦增大14.1%,划痕宽度增大39%。随着划擦深度的增加,试验划擦力与仿真划擦力均线性增大,且仿真值与试验值误差为18.1%,验证了有限元仿真模型的有效性。超声振动作用下的划擦力呈周期性变化特征,使平均划擦力降低了43.2%。此外,仿真结果表明,超声辅助划擦相较于普通划擦,温度最高降低50%,表面塑性应变最高降低20%,超声冲击过程中材料的塑性应变率相较于普通划擦提高1个数量级,分离过程中塑性应变率最大降低2个数量级。结论 超声振动作用可以有效降低划擦过程中的划擦力和划擦区域温度,增大冲击过程中材料的瞬时应变率,改善压头的切屑黏附现象,从而抑制划擦表面鳞刺的生成和犁沟的形成,改善表面质量。此外,超声振动作...     

Friction and multiple scratch behavior of polymer+monomer liquid crystal systems

We have studied in turn: polystyrene (PS), styrene/acrylonitrile (SAN) and Polyamide 6 (PA6), adding each time to the polymer 1, 3, 5, 7 or 10 wt% of 4,4′-dibutylazobenzene (LC1) which is a monomer liquid crystal (MLC). LC1 reduces both static and dynamic friction of PS and SAN against stainless steels or polytetrafluoroethylene (PTFE). By contrast, friction values are lower for pure PA6 than for PA6 modified with various MLCs or with MoS₂.Multiple scratching tests were carried out with a micro scratch tester on every system between 2.5 and 15 N. The presence of LC1 in PS reduces penetration depth and residual depth and increases the viscoelastic recovery. So far PS was the only polymer, which does not show strain hardening in multiple scratching. The present results confirms this, but it also shows that only 1 wt% of LC reduces the brittleness of PS so that strain hardening appears. This effect is maintained at all higher concentrations of LC1 investigated as well. For SAN or PA6, additions of LC1 reduce penetration depth values with respect to pure polymers, but do not have a significant effect on viscoelastic recovery. Scanning electron microscopy (SEM) was used to study the deformation and wear mechanisms, and to relate the data obtained in multiple scratch sliding wear tests. For PS we see in SEM that increasing the LC1 concentration causes a more ductile behavior, with less crack nucleation. For SAN the debris accumulation in sliding wear is mitigated by the presence of the liquid crystalline lubricant. No debris formation is observed in PA6, with or without a lubricant.     

膜—基界面结合性能激光划痕检测方法技术优势分析

提出红外激光划痕准静态测量新方法。在分析传统划痕试验法和激光检测技术研究与应用现状的基础上 ,进行了激光划痕法的技术优势分析。     

Investigation of the Synergism of Wear and Corrosion Using an Electrochemical Scratch Technique

Corrosive wear of materials is a complicated surface failure process. The synergism of wear and corrosion involves both the wear-accelerated corrosion and the corrosion-accelerated mechanical failure. In this work, attempts were made to determine mass losses from these two processes using an electrochemical scratch technique. 340 stainless steel and a cast iron were studied as sample materials. For both the materials, the wear-accelerated corrosion was significantly higher than the static corrosion, due to the failure of passive film or adsorption layer. Regarding the corrosion-accelerated wear, 304 steel showed higher resistance, attributed to its passivation capability and associated protective passive film.     

缓蚀剂对原子力显微镜探针刮擦铜镍合金加速溶解的作用

金属材料在缓蚀剂中受到刮擦会加速溶解,产生相应的腐蚀.采用原子力显微镜(AFM)探针刮伤技术研究了缓蚀剂对探针诱导铜镍合金加速溶解作用的影响.结果表明:在750 nN负载条件下,AFM探针在接触模式下对铜镍合金表面持续扫描,可以加速样品在1.5 mol/L NaCl溶液中的溶解,探针刮擦区域有蚀坑;作为缓蚀剂添加的有机化合物十二胺和无机盐铬酸钠能抑制探针刮擦引起的铜镍合金的加速溶解.     

Observing Conspecifics Scratching Induces a Contagion of Scratching in Japanese Monkeys (Macaca fuscata).

Although a large number of studies have examined self-directed behaviors (SDBs) such as scratching and self-grooming as nonverbal leakage of negative emotional arousal in humans, few studies have investigated the informative function of SDBs in nonhuman primates. The present study investigated whether viewing another monkey scratching itself elicited negative arousal from conspecific observers in Japanese monkeys (Macaca fuscata). An experimental situation was created in which the target monkey watched a stranger through a small peephole and the observer monkey(s) watched the target in turn. Scratching spread when conspecific observers watched the target scratching itself while performing monitoring behavior. The author proposes that the possible contagion of scratching by monkeys observing another's scratching may involve transmission of a psychological state, a primitive style of empathy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

改善酸轧机组测张辊表面划伤的研究

分析了宝钢 1 42 0冷轧酸轧机组 4#机架后的测张辊在正常轧制中产生的划伤问题 ,通过对测张辊的表面状态、辊径、安装高度以及轴承的改进 ,彻底解决了因测张辊表面划伤而直接导致带钢表面划伤的产品质量问题。