涂层结构设计对等离子喷涂陶瓷层结合强度及其应力的影响

用等离子在45#碳钢上喷涂了不同涂层设计的Al2O3以及Al2O3+130mg·g-1TiO2陶瓷层.用X-射线衍射法和拉伸实验测量了涂层表面层中的残余应力及结合强度.增加粘结层和过渡层能大大地克服陶瓷涂层与基材机械的以及热的不匹配性,使涂层的应力和结合强度都得到明显改善.此外,SiO2能改善ZrO2陶瓷层与基材以及陶瓷层内部的结合程度,使涂层内应力松弛并使其结合强度提高.然而SiO2添加剂只有在高熔点陶瓷层中(如ZrO2),"液相烧结"作用才明显,而在熔点较低的陶瓷层中(如Al2O3),这种作用并不明显.在用等离子喷涂低熔点Al2O3陶瓷时,添加适量的低熔点TiO2陶瓷是必要的.     

Al2O3涂层碳纤维/环氧基复合材料的性能研究

采用溶胶-凝胶法在碳纤维的表面涂覆了一层Al2O3涂层,透射电镜分析表明涂层中粒子的大小约为10nm,接触角分析表明涂层后碳纤维的表面张力有大幅提高.通过比较涂层前后碳纤维/环氧复合材料的力学性能发现,Al2O3涂层后复合材料的层间剪切强度,拉伸强度和弯曲强度分别提高了17.7%,4.8%和3.1%.扫描电镜分析表明,Al2O3涂层后的碳纤维与环氧树脂基体的结合更加紧密.且在碳纤维表面形成的Al2O3涂层在350℃～700℃能有效地减缓碳纤维环氧基复合材料的氧化失重速率.     

自蔓延高温合成反应热喷涂Al2O3基复相陶瓷涂层的性能

为了改善AZ31B镁合金的耐磨性,以Al2O3-13%TiO2为陶瓷骨料,在其中加入Al/CuO铝热荆,采用普通氧乙炔火焰自蔓延高温合成反应热喷涂技术在镁合金表面制备Al2O3基复相陶瓷涂层.通过X射线衍射分析了陶瓷涂层的组成.结果表明,所得复相陶瓷涂层具有良好的抗热震性,涂层内有Cu4MgO5,CuAlO2等新的物相产生.磨粒磨损试验、黏着干磨损试验和黏着油磨损试验表明:自蔓延反应热喷涂陶瓷涂层的耐磨性是AZ31B基体的6.48,3.32,6.04倍,普通热喷涂层的耐磨性是AZ31B基体的3.60,1.76,1.67倍,自蔓延反应热喷涂陶瓷涂层的耐磨性比普通热喷涂层有较大提高.     

Al2O3涂层相变对石英纤维及其磷酸铬铝复合材料性能影响

采用溶胶-凝胶法制备了Al2O3溶胶,通过TG-DTA-DSC、FT-IR、XRD、SEM等测试手段研究了Al2O3涂层相变规律,探讨了涂覆在石英纤维上的Al2O3涂层在不同温度处理下,石英纤维的耐酸性、抗拉伸强度和抗氧化性能及其复合材料性能的影响。结果表明,经过300℃处理后的Al2O3涂层,能均匀地包覆在石英纤维表面,增强石英纤维的耐酸性、抗拉伸力和抗氧化性能,改善石英纤维与酸性磷酸盐基体材料的结合,增强复合材料的力学性能。     

等离子喷涂Al_2O_3-13%TiO_2涂层微观组织结构与力学性能分析

采用等离子喷涂技术在钢基体上表面制备了Al2O3-13%TiO2涂层,喷涂粉末分别采用微米和纳米结构,测试了涂层的显微硬度;采用定量分析软件测定了涂层孔隙率并通过扫描电镜分析了涂层的显微组织;采用拉伸试验机测试了涂层的结合强度。结果表明,微米粉制备的Al2O3-13%TiO2涂层具有明显的层状结构,纳米粉制备的Al2O3-13%TiO2涂层在层状结构的基础上镶嵌有大量的未融化和部分融化的粒子;纳米Al2O3-13%TiO2涂层粒子间结合紧密,孔隙率低,结合强度高,显微硬度高。     

耐锌蚀陶瓷防护层的制备与腐蚀机理初探

采用电弧喷涂法预先在Q235钢试样基体上喷涂FeCrAl粘结层,再利用等离子弧喷涂制备Al2O3陶瓷涂层,分析了陶瓷涂层在500℃静态锌液腐蚀试验中的腐蚀机制及影响因素.通过SEM和XRD分析可知,Al2O3陶瓷涂层与锌液为不互溶材料,起隔离基体与锌液、防止铁锌发生互扩散反应的作用.试验结果表明,等离子喷涂的Al2O3陶瓷涂层能极大地延缓Q235钢腐蚀失效的时间,耐液锌腐蚀性极好;陶瓷涂层的结合强度和涂层厚度是影响耐锌蚀性能的主要因素.     

等离子喷涂制备铪酸钇热障涂层及其性能的研究

采用大气等离子喷涂(APS)设备在高温合金(GH49)基体上制备了Y2Hf2O7热障涂层.采用金像显微镜对所制得涂层的截面进行观察,并对其孔隙率进行测量,测得结果为13.77％.采用对耦拉伸法对制得涂层的结合强度进行测试以检验涂层基本性能,所得结合强度为25.13MPa.为检验涂层抗热冲击性能,对涂层试样实施整体热冲击实验,经10次整体热冲击后表现为边缘处出现少量的剥落,其失效主要是在陶瓷层粒子与黏结层的界面处.陶瓷层与金属黏结层界面处因热膨胀系数差异导致的热应力和陶瓷层自身强度较低是涂层失效的主要原因.     

钛合金表面阴极微弧电沉积Al2O3-SiC复合涂层

通过高温烧结法在TC4钛合金表面制备了起弧阻挡层,然后采用阴极微弧电沉积工艺在TC4钛合金表面制备了Al2O3-SiC复合陶瓷涂层,重点研究了复合陶瓷涂层的制备工艺及影响因素,并采用扫描电镜、能谱仪等观测了起弧阻挡层及复合陶瓷涂层的表面微观形貌及成分组成。结果表明,阴极微弧电沉积技术能够在钛合金表面制备出Al2O3-SiC复合涂层,且起弧阻挡层至关重要,为起弧必备条件,SiC在Al2O3基体中的分散性较好,涂层较厚且分布均匀。     

Ti(CN)/TiC/Al2O3/TiN多层涂层的结构和界面结合力研究

采用中温、高温复合化学气相沉积技术(MHCVD)在WC- (6％wt)Co硬质合金基体表面制备了Ti(CN)/TiC/Al2O3/TiN 多层陶瓷涂层.通过光学显微镜(OM)、扫描电镜(SEM)、X射线衍射仪(XRD)和数显显微硬度计等手段分析多层陶瓷涂层的表面及断面形貌、物相组成、显微硬度;采用表面划痕实验,结合形貌观察及X射线能谱分析(EDS)研究多层陶瓷涂层/硬质合金基体的界面结合力及其影响因素.结果表明:Ti(CN)/TiC/Al2O3/TiN 多层陶瓷涂层结构均匀致密,涂层后硬质合金的显微硬度明显提高,约2600 HV,多层陶瓷涂层与基体界面结合良好,划痕实验显示临界载荷高达105 N,多层陶瓷涂层界面间的原子扩散作用对涂层/基体界面附着力有较大贡献,而涂层内部少量Ti2O3、W6Co6C 等物相的存在对提高界面结合力也有帮助.     

Ti-Al球磨粉反应等离子喷涂涂层的组织与性能

为制备Ti-Al金属间化合物复合涂层并研究其性能,以机械球磨的Ti-Al混合粉在Q235钢表面进行反应等离子喷涂实验,分别采用X射线衍射、扫描电子显微镜对涂层的成分、显微组织进行了分析,并测试了涂层的结合强度、显微硬度和耐腐蚀性能.结果表明:涂层由Al3Ti、TiN、Al2O3、少量TiAl与Ti3Al、以及残留的Al和Ti组成;球磨可促进喷涂时的反应,但喷涂时Al和Ti仍未完全反应,且在空气环境中喷涂容易氧化和氮化;涂层与基体之间是镶嵌式的机械结合,结合强度平均为30.24 MPa;涂层表面的显微硬度平均为206.1 HV,涂层的耐腐蚀性优于基体.总体上看,当球磨时间较长、电流较大、喷涂距离较大、气流量较小时,喷涂时的反应较充分,且涂层比较均匀、致密,其强度、硬度以及耐腐蚀性能较高.     

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.     

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.     

Investigation of the Corrosion Behaviors of HVOF-Sprayed Carbide Cernet Coatings in Molten Al-Zn-Si Alloy Bath

In continuous hot-dip galvanization process the corrosion and chemical stability of the sink roll in the galvanizing bath are important problem which effects on the quality and productivity. In order to protect the sink roll the carbide cermet and/or ceramic coatings were deposited on the surface of the sink roll. The WC-, Cr3 C2-cermet coatings were deposited by high velocity oxygen fuel (HVOF) spray, respectively. The coating samples were immersed in molten Zn-alloy containing 50 wt % aluminum at 833 K for 24 hr and 144 hr, respectively. The inter-diffusion and inter-reaction of Zn, Al and elements in coating and corrosion behaviors of these coatings were investigated by XRD, SEM and EPMA etc. The corrosion mechanisms of the carbide cermet coatings and ceramic coatings in molten High Al-Zn-alloy were approached.     

Fundamental study of adhesion of ice to cooling solid surface (Discussion on influence of copper oxide layer on ice adhesion force)

In many situations, ice often adheres to a cooling solid surface, frequently causing serious accidents. It is critical to clarify the mechanism of ice adhesion to the cooling surface in order to prevent ice adhesion. In a past study, the shearing stresses of two kinds of test plates with a copper surface having the higher thermal conductivity were measured. The shearing stress corresponds to ice adhesion force. Both shearing stresses were significantly different; however, the cause remains unclear.Therefore, the present study focuses on an oxide layer as the main factor causing the difference of both shearing stresses; the influence of the oxide layer formed on shearing stress was discussed. And in the removal and reformation processes of the oxide layer, the time variation of the shearing stress was clarified. Moreover, the relationship between the state of the copper surface and the shearing stress was also clarified by surface analysis.     

重塑标准推行格局 推动LED照明的普及（英文）

正When you are enjoying the green,energy-saving and healthy lighting of IKEA LED luminaire,you may not realize that most of IKEA’s LED bulbs are produced by the LED luminaire smart manufacturing system of Hangzhou Zhongwei Photoelectricity CO.,LTD(ZVISION).No longer enclosed in the laboratory,the product standards are brought into the factory workshop and even to the entire production process.Thus,the standards are promoted and applied in a favorable way by enterprises,benefitting consumers with high quality products.     

Chinese Experts Contribute to ISO＇s New Toy Standards

正The international standard,ISO 8124-6,Safety of toys–Part 6:Certain phthalate esters in toys and children’s products,was officially issued by ISO worldwide on August 15.It was the first time for Chinese experts to lead the ISO standard development in toys industry.The standard was drafted by a group of Chinese experts from SAC/TC for toys and relevant Chinese departments and finally completed by a dedicated international group of experts.ISO 8124-6 makes a substantive breakthrough in the aspects of the scope of toys,limitation of plasticizer types,control of test cost,accuracy of test,operation convenience,etc.,offering the operational guidance for toy manufactures and testing laboratories.     

中国质量(北京)大会(英文)

正Themed on"quality,innovation,development",the first China Quality Conference(Beijing)was held in the Great Hall of the People on September 15.Chinese Premier Li Keqiang delivered an important speech at the conference.State Councilor Yang Jing and Wang Yong attended the conference with over 600 domestic and international representatives from foreign,regional and international quality organizations     

National Working Meeting on Land and Resources Standardization

正The National Working Meeting on Land and Resources Standardization was held in Beijing on July 15,2014.Wang Min,the Deputy-Minister of the Ministry of Land and Resources,and Yin Minghan,the Chief-Engineer of SAC addressed the meeting.Representatives from relevant competent departments and technical committees were present.The meeting aims to summarize work,discuss existing problems and make clear working thoughts,promoting standardization work of land and resources to a new level.Wang Min pointed out that the standardization work of land and resources should be centered on the basic principles of"protecting land and resources dutifully,intensively and economically utilizing land and resources,and making all-out efforts to safeguard the public’s rights and interests",highlighted the