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1、1.0introduction 介绍介绍 1.1test scope 试验范围 this standard specifies an accelerated laboratory atmospheric corrosion test. the testing environment addressed is similar in effect to that of the salt load/ climatic part of the proving ground corrosion test procedure, cetp 00.00-r-343 and yields correspondi
2、ng results. the objective of the test is to allow evaluation of the corrosion resistance of metals in environments where there is a significant influence of chloride ions, mainly as sodium chloride from a marine source or by winter road de-icing salt. the laboratory test provides full exposure to th
3、e salt load and humidity environment. it does not attempt to simulate other engraving factors such as mud loads, temperature stresses or wear. it serves as a general purpose atmospheric corrosion test and applies to a variety of materials, coatings, and interactions of materials, both as test specim
4、ens or in designed components. the test can be used as a design verification method in order to (a) develop and qualify new corrosion resistant products, (b) develop new pre- treatments and finishing processes, (c) select materials and, (d) perform quality control of the final product. 本标准是关于一项在实验室里
5、加速进行的大气腐蚀试验。本文所述的试验环境类似于 试验场腐蚀试验程序cetp00.00-r-343中的盐负荷/环境影响部分,得出相应的结 果。试验目的在于评估金属在富含氯化物的环境中(主要是海水中的盐或冬天用于融雪 的盐)的抗腐蚀性。该实验室试验主要是将试验件完全暴露在湿润的盐负荷环境中,而 非模拟其他摩擦因素如泥负荷、温度压力或磨损。该试验主要作为一项大气腐蚀试验, 适用于各种各样的材料、涂层、试样或设计零部件材料的相互作用。该试验可作为一种 验证设计的方法,用于(a)开发并验证新的抗腐蚀产品;(b)开发新的预处理和表面处理工 艺;(c)选择材料;(d)对最终产品的质量控制。 the sta
6、ndard specifies controlled conditions for equipment and procedures to allow the test to be performed with a high degree of repeatability and reproducibility. it is designed to be suitable to run in various climate chambers, either as a fully automated procedure or with partial manual operations. 本标准
7、说明了设备和程序的受控条件,让实验具有高度的重复性和再现性。本标准适用 于多种环境试验箱,包括全自动试验或部分手动操作的试验。 1.2summary of test content 试验内容摘要 the workday test procedure consists of: 工作日的试验程序由以下几个方面组成: a 6 h wet phase at room temperature. with intermittent exposure to salt solution (0.5% nacl). a 2.5 h transition phase with drying under climat
8、e control. a 15.5 h phase with constant temperature and humidity (50c, 70% rh). 室温下6小时的加湿阶段,间歇曝露到0.5%的氯化钠溶液中 2.5小时的过渡阶段,通过环境控制进行烘干 15.5小时的恒温恒湿阶段(50c, 70% rh) after repeating this procedure mon-fri a 48 h weekend phase under continued constant climate control is added. 从周一到周五重复该试验程序后,在周末加入持续恒定环境控,进行4
9、8小时的试验。 1.3commonality 共通性 this is a control test and can be used to qualify components throughout the world. the test may be conducted at any location having the necessary equipment and facilities. proposed revisions to this procedure must be submitted per fap03-179. 这是一项可验证世界上所有的零部件的控制试验,可在任何地方进行,
10、只要具备所需的 设备仪器。对本试验程序的修改建议必须按fap03-179提交。 2.0instrumentation 仪器仪器 the following elements are usually required to conduct the test procedure: 进行试验程序一般需要以下仪器: 2.1compressed, clean air of 4 - 6 bars for cleaning salt solution from spray nozzles, as a source for the renewal of chamber air and for humidifi
11、cation, supplied by spray humidifiers. 2.1 4-6 bar的干净的压缩空气,用于清理喷嘴上的盐溶液、箱内换气和喷雾加湿器进行加 湿。 2.2a low conductivity water supply (20 s max) for humidification or evaporative spray humidifiers and for the preparation of salt solutions. 2.2 一根低导电率的供水管(最大20 s),用于加湿或喷雾加湿器以及准备盐溶液。 2.3a tank for preparation and
12、 storage of salt solution or, alternatively, a system for direct on-line mixing of water and saturated nacl solution to the actual concentration (0.5 0.05% by weight) 2.3 一个用于准备和存储盐溶液的水槽,或者一套直接在线按实际浓度(0.5 0.05%,按重 量)混合水和饱和氯化钠溶液的系统。 2.4a conductivity meter with built-in temperature compensation for p
13、reparation and control of the 0.5% nacl salt solution (conductivity: 8.3 ms/cm + 0.80 at 20c). a 0.50% by weight nacl solution is used as a calibration standard at each measurement. 2.4 一个带内置温度补偿的电导仪,用于准备和控制0.5%的氯化钠盐溶液(温度为20c时的 导电性:8.3 ms/cm + 0.80)。 一份按重量为0.50%的氯化钠溶液,作为每次测量时的校 正标准。 2.5a high qualit
14、y device for independent control of temperature and relative humidity shall be accessible. this instrument shall on a stipulated regular interval (ref 5.4) be used for independent monitoring and calibration of the conditions in the very test plane of the exposure chamber. the total measurement error
15、 must not exceed 0.1c. 2.5 一套高质量的设备,用于独立控制温度和相对湿度。该设备按照规定的时间间隔(参考 5.4),独立监控和校正试验箱李的试验平面上的各项条件,测量总误差不超过0.1c。 2.6racks of inert material for support and aligned fixation of test specimens must not hamper a free air-flow around the test objects, nor collect standing wetness. the test objects in a rack
16、must not screen one another from the salt solution downfall and they should be exposed with the stipulated exposure angle to the spray (15- 20 degrees inclination from vertical). 2.6 由惰性材料制成的夹具,用于支撑、排列和固定试样,但不得妨碍试样周围的空气流 通,不得累积水分。夹具上的试样不得相互遮蔽导致盐溶液淋不到试样上。试样应按规 定的角度曝露到喷雾中(偏离垂直线15-20度)。 2.7pressurized
17、hand-spray equipment for application of the 0.5% nacl solution if a manual spray procedure is used. the capacity must be sufficient to meet the downfall requirement (ref. 3.3.1). 2.7 如需采取手动喷洒,应使用适用于0.5%盐溶液的加压型手动喷雾器,喷雾器的容量必须 能满足喷洒要求(见3.3.1)。 2.8funnels, beakers/ measuring glasses and a balance with a
18、t least 0.1 g accuracy for monitoring and calibration of salt solution downfall throughout the test plane of the exposure chamber. 2.8 漏斗、烧杯/量杯以及精确度至少为0.1g的天平,用于监控和校准曝露箱中试验平面上落 下的盐溶液。 2.9all test measurement equipment must be calibrated and maintained per fap03-015, control, calibration, and mainten
19、ance of measurement and test equipment. 2.9 所有试验的测量设备的校准和维护必须按照fap03-015测量和试验设备的控制,校准 和维护程序。 2.10all applicable safety guidelines and procedures must be followed. 2.10 试验须遵守所有适用的安全指引和安全程序。 3.0equipment and facilities 设备设施设备设施 the necessary, permanently installed facility to conduct the test consists
20、 of a programmable humidity chamber of good quality. it is preferably equipped with an integrated rig for spraying salt solution of the required amount and accuracy, cooling capacity and a good internal circulation system for the conditioned air (fig. 1). the exposure chamber shall be designed so th
21、at the test conditions described in the subsequent paragraphs can be obtained, controlled, and monitored during the test. 试验所需的永久性安装的设施包括一个可编程的高质量湿度箱。湿度箱中最好能配备一 套喷量准确度高的综合性盐雾喷洒装置、冷却装置和一套性能良好的空气内循环系统 (如图1)。曝露箱应按要求设计,以使下文所述的试验过程中的各项条件能在得到满 足、控制和监控。 1 3 6 6 8 7 7 4 11 5 2 8 9 10 fig. 1 schematic view o
22、f a climate chamber equipped with functions suited for performance of the described test procedure: 1. chamber test space, 2. climatization unit, including fan, heating, cooling and humidification, 3. test plane with samples, 4. temperature/ humidity sensor for regulation, 5. insulated walls/ lids,
23、6. diffusors for improved air distribution, 7. fresh air inlet/ bleed, 8. rain rig with nozzles and motor for swaying mode, 9. gutter, 10. control/ steering/ recording unit, 11. position for monitoring/ calibration of climate with independent temperature/ humidity sensor. 图1 环境试验箱的图示,配备了进行本文所述的试验程序所
24、需的功能:1. 试验空间;2. 环境系统,包括风扇、加热器、冷却器和加湿器;3. 放置试样的平面;4. 温湿传感器 (调节用);5. 隔热壁/盖; 6. 空气扩散器(改善空气分布);7. 新鲜空气进气口; 8. 带喷头和摇摆模式驱动马达的喷洒器;9. 排水口;10. 控制/操作/记录系统;11. 带独立 温室感应器的环境监控/校正位置。 3.1climate control 环境控制 the humidity and temperature levels of the chamber during the test cycle shall be continuously monitored.
25、the sensors should reflect the climate conditions in the test plane (fig. 1, item 4). the mean value of the constant temperature/ relative humidity climate conditions must be within 0.4c and 2% relative humidity (rh) respectively vs. the real, set value, i.e. these are the max tolerable mean offsets
26、 caused by the sum of calibration errors. at annual calibration this degree of accuracy must be fulfilled for the following three constant conditions: 25c, 95% rh, 50c, 95% rh and 50c, 70% rh. at bimonthly control, during normal operation, this accuracy should be fulfilled at the constant climate co
27、nditions (50c, 70% rh) during a work- day cycle. 试验过程中应连续不断地监控试验箱的湿度和温度水平。传感器会反映试验“平面”上 的环境(如图1中第4项)。恒定温度/相对湿度的均值必须在0.4c范围内,相对湿度 (rh)在2%,分别对应实际值、设定值,这些就是由于累积的校正误差造成的平均偏 移值的最大允许范围。 在年度校正过程中,这一精确度必须得到满足,以保证以下三 项恒定条件:25c, 95% rh, 50c, 95% rh以及50c, 70% rh。在进行两月一次的正常 控制时,工作日循环中的恒定环境条件(50c, 70% rh)应能到达这一精
28、度。 the maximum allowed short-term fluctuations in relative humidity overlaid on the calibrated mean value is 3% rh, which implies a maximum allowed short-term temperature fluctuation of 0.6c. figure 2 is exemplifying the requirement on relative humidity. 叠加到校正平均值的相对湿度短期波动最大范围是3% rh。这意味着短期温度波动的 最大范围只
29、能是 0.6c。图2举例说明了相对湿度的要求。 fig. 2 accuracy requirement on humidity deviations from set value 图2 湿度偏差离设定值的精确度要求 the chamber controlling software/ hardware must be designed so that the relative humidity may be changed linearly with time as depicted in the illustrated test conditions, see figure 5. in the
30、 2-stage ramping from a wet chamber at 25 2c to humid conditions at 50c, 70% rh, the first heating stage to 40c should be reached within 30 minutes without sample drying, which is secured by a nominal relative humidity setting to 95% rh. the second 2 h ramp must reach the stipulated final 50c, 70% r
31、h at the end of the ramp. 控制试验箱的软件/硬件必须设计成能使相对湿度随时间呈线性变化,如图5所示。从试 验箱温度为25 2c的湿润状态到50c, 70% rh的湿润状态需经过两个阶段。第一阶段 应通过将相对湿度读数设定到95%rh,以保证温度在30分钟内达到40c而试样不干燥。 第二阶段为两小时,必须在结束前达到规定的50c, 70% rh。 set rh value 相对湿度设定值相对湿度设定值 trueness: max allowed absolute calibration error: 2% rh 真实:最大允许的校正误差绝对 值:20%rh actual
32、 mean rh value 相对湿度实际均值 actual fluctuation around mean rh value 相对湿度均值上下的实际波动 precision: max allowed variation around actual mean value: 3% rh 精确度:实际均值上下允许的最大变 动范围是:3% rh note: for each new exposure situation this condition must be verified by an independent monitoring device (paragraph 2.5) with th
33、e sensor positioned among the actual test objects in their actual average plane of exposure (fig. 1 item 11). for monitoring : deploy the sensor directly after the last spray event of the work-day wet phase. 注意:每次曝露的条件必须经过独立监控设备验证(见第注意:每次曝露的条件必须经过独立监控设备验证(见第2.5段),也就是实际试验物体段),也就是实际试验物体 所在的曝露平面之间的传感器(
34、如图所在的曝露平面之间的传感器(如图1,第,第11项)。在工作日湿润阶段的最后一项)。在工作日湿润阶段的最后一 次喷洒后直接调节传感器来进行监控。次喷洒后直接调节传感器来进行监控。 in automated testing, forced cooling is necessary when proceeding from 50c, 70 % rh controlled, constant conditions to macro-wet conditions at 25c. the chamber must achieve a cooling from 50c to 30c within 30
35、minutes with the targeted 25c met within 1 hour. if spraying is applied manually, then cooling the samples by letting the chamber be open with test objects kept wet may provide an option that does not require the use of a built-in cooling unit. it must be verified by temperature monitoring that cool
36、ing requirements are fulfilled under such conditions for the actual chamber type and test specimen load. 在自动试验过程中,要使试验箱从受控恒定条件50c, 70 % rh变化到25c下非常湿的条 件,需要进行强制冷却。试验箱必须在30分钟内从50c冷却到30c,然后在1小时内到 达目标温度25c。如果是手动喷洒,可以打开试验箱同时让试样保持湿润,这样就不必 使用内置冷却系统。在这种条件下要满足该类试验箱和试样负荷的冷却要求,必须通过 温度监控保证。 3.2recommendations o
37、n test chamber functionality 关于试验箱功能的建议 in order to meet the temperature and humidity accuracy requirements throughout the test area, the chamber should be equipped with means to provide well distributed circulation of conditioned air (meaning a local air velocity of at least a few cm/s over all par
38、ts of the test area, - fig. 1 is exemplifying such a condition). sufficient insulation of the chamber walls and lids is required in order to avoid excessive condensation on these surfaces. the more efficient air circulation, the less insulation is required. 为了在整个试验过程中满足温度和湿度的精确度要求,试验箱应配备能使经调节温湿 度、空气
39、流动性好的装置(试验区域内各部分的内部气流速度至少是若干厘米/秒-例如 图1。)试验箱的四壁和盖板要求得到有效隔热,以避免这些表面出现过渡冷凝。空气 流动性越好,隔热需求越少。 wall heating should be avoided, due to that heating by radiation tends to keep test object close to the chamber walls locally too dry to be within humidity specification (or a screen shall be installed to avoid
40、such an effect). provided the internal air circulation is efficient, wall heating is not required. the chamber air must be continuously renewed by a purge of not less than 1 m3/ h per m2 of test area (exemplified by fig. 1, item 7). this to assure that the co2-level is not significantly depleted und
41、er any exposure conditions. fresh air can be added dry from a compressed source or taken from ambient conditions, unless significantly polluted ( 50 ppb so2). 由于热量辐射会使靠近箱壁的试样过度干燥,达不到湿度要求,因此应尽量避免试验箱 壁受热(或者添加遮挡板来避免受热)。如果内部空气流动良好,就不必进行箱壁加 热。应配备1 m3/ h每m2的空气净化器使试验区域内的空气不断更新(例如图1第7项)。 这是为了保持co2水平,避免其在曝露条
42、件下被耗尽。干燥的新鲜空气可以由压缩机提 供,或使用室内的空气(除非空气被严重污染( 50 ppb so2)。 3.3exposure to salt solution 曝露到盐溶液中 3.3.1for a fully automated procedure , the chamber shall be equipped with a spray device capable of producing a finely distributed, uniform spray falling on the test objects. the most reliable way of receivi
43、ng a fairly uniform downfall is by installing a moving spray device, like the swaying rail with overlapping nozzles, depicted in fig. 3. the spraying device shall be made of corrosion resistance materials. plastic is recommended. 3.3.1 对于全自动的试验,试验箱内应配备喷洒装置,能使溶液得到妥善分配,均匀喷洒到试 样上。最能有效使溶液均匀喷洒的方法是安装一套可移动
44、的喷洒装置,如带交叉喷头的 摇摆轨道,如图3所示。喷洒装置应由耐腐蚀材料制成,最好是塑料。 fig. 3 example of spray rig for obtaining uniform salt solution downfall. 图3 使盐溶液均匀喷洒的喷洒装置示例 a target average precipitation rate distributed over the workday 6 h wet period of this test procedure period is 5 l/m2, and shall not exceed 10 l/m2. for any lo
45、cal position the total precipitation over the 6 h period must not be lower than 3 l/m2 and not exceed 15 l/m2. suggested nozzles type: spraying systems uni jet 800050vp. mount the nozzles on a supporting tube 50-60 cm apart and about 1 m above the test objects. the nozzles shall be adjusted so that
46、the fan plumes are in line with the tube/ supporting rail. an individual filter at each nozzle is strongly recommended to avoid any contaminations in the tiny slots. these low- cost plastic nozzles have a reliable function, but must be inspected in microscope at delivery in order to discard such wit
47、h defect slot cuts. stainless nozzles, even in 316 alloy, will be impaired by corrosion under the actual test conditions. atomizing salt-spray nozzles should not be used, since they generate a too low precipitation rate to give sufficient leaching effect on the test objects. achieving a uniform down
48、fall with these types of nozzles can be difficult. 在本试验的工作日的6小时加湿阶段,平均喷洒密度的目标值为5 l/m2,且不能超过10 l/m2。在6小时周期内,箱内任何位置的喷洒密度都必须不低于3 l/m2,不高于15 l/m2。建议喷头类型:uni jet 800050vp喷洒装置。将喷头装在支承管上,相隔56- 60cm,处于试样上方1米左右。调整喷头,使扇叶与支承管/支承轨成一直线。强烈建议 在给每个喷头装上过滤器,以避免小槽中的污染物。虽然这些喷头价格低廉、功能可 靠,但是发货时还须经过显微镜检验,以淘汰那些小槽切割不良的喷头。不锈
49、钢喷头, 就算是用316合金制成的,在也会在实际试验条件下受到腐蚀而损坏。雾化盐雾喷头喷 洒密度过低,无法为试样起到有效的过滤作用,故不宜使用。这几类喷头喷洒都不均 匀。 3.3.2an automated spray-rig is allowed to be separated from the humidity chamber, i.e. the test objects are moved between two units on a work-day basis. 3.3.2自动喷洒装置可从加湿箱中拆出来。也就是说,试样在一个工作日内在两套设备之间移 动。 3.3.3if there
50、is no possibility to use an automated device for spraying, a manual spraying of the test object is allowed, either in or outside the test cabinet, provided: 1. the minimum precipitation rate of 5 l/m2 per 6 h wet session is fulfilled, 2. the spraying events are distributed over the 6 h period, so th
51、at the test object are kept constantly wet, and 3. the temperature requirement is fulfilled. 3.3.3如果不能采用自动喷洒装置,可采用手动喷洒,在箱内箱外皆可,条件是:1. 在6小时 加湿阶段完成前,喷洒密度至少为5 l/m2。2. 喷洒将分布在6小时周期内,以使试样保 持湿润;并且;3. 保持要求的温度。 note: salt solution sprayed onto test objects must not be reused. 注意:喷洒到试样上的盐溶液不得重复使用。注意:喷洒到试样上的盐溶
52、液不得重复使用。 4.0sample preparation 试样准备试样准备 sample preparation before exposure, the sample orientation during exposure and the evaluation after exposure are usually stipulated in the engineering test standards addressing this test procedure. 曝露前试样准备,曝露期间的朝向和曝露后的评估方法一般会在本试验程序相关的工程 试验标准中关于有所规定。 4.1painted
53、 and scribed panels: the test is optimized for exposing scribes in horizontal position on panels oriented to the angle stipulated in paragraph 5.1.1. scribe orientation has a similar effect on salt collection as the panel orientation. the scribe, or other type of damage, shall be positioned, so that
54、 a collecting area for precipitation is left above the exposed area of interest. 4.1 喷漆板和划线板:本试验已针对水平划线的板材按第5.1.1段所规定的角度朝向曝露进行 了优化。划线的朝向的作用类似于板材朝向的盐聚集。划线或其他损伤都应定好位置, 以便喷洒液收集区域位于目标曝露区域之上。 4.2component parts are to be in vehicle orientation position if at all possible. the salt solution spray should r
55、each the areas of interest. 4.2 如果可能,零部件应尽量按照汽车朝向放置,并使盐溶液能淋到达目标区域。 4.3interested parties should agree on the location within the components where the corrosion is to be observed. 4.3 相关各方需商定零部件上将出现腐蚀的位置。 4.4interested parties should agree to any pre-conditioning, masking of edges, pre-testing, clean
56、ing, or any other sample preparations. 4.4 相关各方需商定预处理、要遮盖的边缘、预测试、清洁或其他试样准备工作。 4.5interested parties should agree to any photographic details throughout the test and the areas to be examined and any assessments that are required. 4.5 相关各方需商定试验过程的具体细节、检测的区域以及要求的评估。 5.0operation 操作操作 5.1before test sta
57、rt 试验开始之前 prepare test objects according to the instructions in paragraph 4, which may include additional procedures, like preconditioning in other test equipments (e.g. heat treatment). 按照第4段的说明准备试样,也许将包括附加步骤,如在其他试验设备中进行预处理 (比如热处理)。 5.1.1 test object orientation: components or test objects in the c
58、hamber shall be placed on/ mounted to non-corrosive surfaces in the appropriate agreed upon position. if the item is flat the test surface shall be within an 15-20 angle from vertical. note that the inclination determines the amount of wetness collected on the panel and hence, the salt load when thi
59、s film is subjected to climate control, which in turn influences the test result. 5.1.1 试样的朝向:试验箱中的零部件或试样应按照商定的朝向,放置或固定在防腐蚀的表面 上。如果试样是平的,那么试验表面应在离垂直线15-20角度范围内。请注意,板的倾 角决定了溶液的收集量,从而影响试验片受环境控制时的盐负荷,进而影响试验结果。 5.1.2test object support: if it is necessary to suspend the objects, the material used shall be made of non-metallic inert materials. the test stands must not obstruct passing of air, nor disable proper drainage (the photo in fig. 4 shows an example of open well-drained supports for flat panels) 5.1.2试样的夹具:如需将试样托起,夹具应采用非金属的惰性材料,而且不得阻碍空气流通 或排水(图4就是一
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