碳钢制品仓储周转期间的防锈方案设计

碳钢材质汽车零部件产品在生产的全过程中,仓储周转是必不可少的环节.为了避免锈蚀发生,同时兼顾经济性,仓储周转期间的产品防锈方案必须和生产计划紧密结合,在满足生产的前提下达到防锈方案的优化.根据不同存储周期的要求,通过试验选择合理的防锈材料,为有效解决零件的锈蚀问题提供适用、经济的防锈方案.采用水基防锈剂、水基防锈剂与气相防锈纸(复膜)配合、碳氢防锈剂与塑料袋配合3种防锈方案,分别可实现零部件仓储周转期间1个月、6个月及12个月存储期的防锈.     

一种环保型水基防锈剂的性能研究

以往的水基防锈剂不仅对环境不利,同时会影响后续的工艺质量。研制了一种环保型水基防锈剂,主要组成为30 g/L聚马来酸酐,20 g/L苯甲酸钠,6 g/L钼酸钠,8 g/L三乙醇胺及0.3 g/L苯并三氮唑。通过对其防锈性能、焊接性能及与油漆的配套性能的综合研究,结果表明:该环保型水基防锈剂不仅较某品牌防锈剂具有更好的防锈性能,对金属基材的使用性能,如焊接性能、与各类油漆配套性能也没有不利影响,具有较好的推广应用前景。     

环保型水基防锈剂的研制

为了克服目前水基防锈剂防锈效果差、含亚硝酸盐等有毒物质以及成本较高等缺点,以硅酸盐为主料,与多种不同类型的防锈助剂进行复配,制备了环保型水基防锈剂.通过外观表征、NaCl盐水浸泡、湿热试验、Tafel极化曲线测试和扫描电镜观察等方法对制备的防锈剂的性能进行评价,选出了与硅酸盐具有协同作用的物质.通过正交试验确定了防锈剂...     

钢铁件涂装前处理除锈防锈剂的研制

为了解决涂装前处理人工除锈效率低、普通酸除锈易返锈和积留残酸等问题,通过探讨除锈防锈剂的作用机理和进行成分筛选试验,研究了除锈防锈剂的成分和工艺条件对其除锈防锈性能的影响,确定了除锈防锈剂的最佳配方和工艺,除锈防锈效果优良.该除锈防锈剂在金属表面形成磷酸盐保护膜,既可作为普通金属除锈防锈剂使用,也可作为金属涂装前处理剂使用.     

水基切割液防锈剂的复配及其防锈效果

水基切割液钼酸盐防锈剂防锈效率低、对电导率影响大。以油酸、二乙烯三胺合成咪唑啉,经烷基化合成水溶性咪唑啉季铵盐,并与钼酸铵、葡萄糖酸钙一起复配成水基切割液防锈剂。采用电导率仪和电化学方法分析了水基切割液的电导率和腐蚀参数。结果表明:水溶性咪唑林季铵盐和钼酸铵起主防锈作用,葡萄糖酸钙起协同作用;钼酸铵含量对水基切割液电导率的影响最大;水基切割液的最优配比为1 000.0(水基切割液)∶2.0(水溶性咪唑季铵盐)∶1.0(钼酸铵)∶0.1(葡萄糖酸钙);水基切割液呈黄色;45钢在含防锈剂水基切割液中的腐蚀速率为0.240 9 mm/a,缓蚀效率达77.58%,电导率仅增加13.00%。     

铬锰合金钢防锈包装实验研究

为了对铬锰合金钢的防锈包装设计提供基本参数,通过实验研究了铬锰合金钢锈蚀与环境相对湿度及时间的关系,对几种典型的防锈包装技术的防锈效果进行了对比分析。结果表明:在自然环境下,铬锰合金钢自身的防锈性能可以保证至少35 d的防锈期,35 d后锈蚀就会出现并随着相对湿度的增加而加速;防锈包装以防锈剂和防锈膜组合为最佳。将研究结果应用到某铬锰合金钢制品的防锈包装,并通过加速试验进行了防锈效果验证。结果表明,该防锈包装至少可保证被包装产品1年内不出现锈蚀现象。     

三乙醇胺硼酸酯的合成及其防锈性能

以n(硼酸)/n(三乙醇胺)=1.0∶1.2,温度140~145℃,时间4 h为条件合成三乙醇胺硼酸酯。用傅里叶变换红外光谱和元素分析对合成物进行表征,并且对其水解稳定性进行了测试,考察了其水溶液的防锈性能。结果表明:以不同的含量加入水中,室温下将20钢、45钢和灰口铸铁浸入其中10 d,0.5%三乙醇胺硼酸酯溶液对20钢有良好的防锈效果,0.6%对45钢有较好的防锈效果,0.8%对灰口铸铁有良好的防锈效果;2.5%的三乙醇胺硼酸酯水溶液对20钢、45钢、灰口铸铁具有良好的防锈性,可作为金属加工防锈剂使用。     

新型无痕水基防锈剂的制备及其在刹车盘前处理工艺中的应用

为了解决刹车盘工序间防锈的问题,采用单乙醇胺、二十一碳三元脂肪酸、二元有机磷酸等制备了一种刹车盘专用无痕水基防锈剂;通过电化学分析、QB/T 2117-95和JB/T 9181-2016的检测以及在刹车盘生产线的应用试验对该水基清洗剂进行了检测表征.结果表明:该防锈剂具有较强的防锈性能,添加浓度为1％时即可通过标准要求,最佳添加浓度为1％～2％,可应用于有磷化工艺的前处理生产线中.     

热塑性树脂在机床、刀具表面防锈上的应用

介绍了以热塑性树脂为主要成膜物质 ,加入防锈剂和改性剂制成热熔型和溶剂型可剥离防锈包装材料 ,并叙述了其在刀具和机床防锈方面的应用情况。     

环保型水基防锈剂的合成及其性能

苯丙乳液成膜性、耐候性、耐水性及耐盐雾性能均较好,而目前用其制备防锈剂的研究较少。采用丙烯酸丁酯、苯乙烯、丙烯酸等单体合成了固含量为48%,粒径为100~140 nm的改性苯丙乳液,以其为主要原料,与缓蚀剂苯并三氮唑和乌洛托品、助剂乙二醇和三乙醇胺等复配,制备了改性苯丙乳液水基防锈剂。通过电化学测试、中性盐雾腐蚀、油漆配套性试验和扫描电镜观察等方法对制备的防锈剂的性能进行评价。结果表明:Q235钢涂抹该水基防锈剂后,腐蚀电位正移,腐蚀电流密度降低了约2个数量级;与市售403防锈剂相比,该水基防锈剂具有良好的防锈性能,防锈膜与油漆配套性能良好,附着力达到1级。     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Effect of Permeable Crystalline Material on Steel Reinforcement Corrosion of Concrete

Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion.     

The Research and Application About "Dry Peeling Off" Technology for Airplane Surface Paint Layer

In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment.     

Quality Study of Honeycomb Core Shaping Without Wax Stabilization

Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

In-process thermal treatment of polylactic acid in fused deposition modelling

Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets.