1.1 本试验方法定义了评估飞机维修化学品腐蚀性的程序，当飞机结构常用的铝合金接合面（三明治）之间存在腐蚀性时。本试验方法旨在用于鉴定和批准飞机维修作业中使用的化合物。 1.2 以国际单位制表示的数值应视为标准。括号中给出的值仅供参考。 1.3 本标准可能涉及危险材料、操作和设备。本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 具体危险说明见第节 9 . 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 本试验方法产生的数据应用于确定飞机结构铝合金是否容易因在日常维护操作中使用试验材料而受到腐蚀或损坏。 5.2 夹层腐蚀试验结果的解释基于对三组试件接合面外观的比较。一组试样仅在接合面中暴露于试剂水，以建立基线（对照），与暴露于试验材料的面板进行比较。 忽略试样切割边缘的腐蚀。 5.3 提供了相对腐蚀严重度评级系统，以允许对试验结果进行数字分类，并消除详细重量损失测量的必要性。点蚀为4级广泛（严重）腐蚀，其重量损失可以忽略不计。 5.4 相对腐蚀严重度评级系统: 外观/腐蚀: 0-无可见腐蚀和变色 1-极轻微腐蚀或极轻微变色，和/或高达5 % 面积的 A. 腐蚀 2-变色和/或高达10 % 面积的 A. 腐蚀 3-变色和/或高达25 % 面积的 A. 腐蚀 4-变色和/或超过25 % 面积的 A. 腐蚀和/或点蚀 目前 （A） “面积”是指滤纸下的面积，或者如果没有使用滤纸，则指施用试验材料的面积。

1.1 This test method defines the procedure for evaluating the corrosivity of aircraft maintenance chemicals, when present between faying surfaces (sandwich) of aluminum alloys commonly used for aircraft structures. This test method is intended to be used in the qualification and approval of compounds employed in aircraft maintenance operations. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information. 1.3 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements appear in Section 9 . 1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The data generated by this test method shall be used to determine whether aircraft structural aluminum alloys are liable to be corroded or damaged by application of the test material during routine maintenance operations. 5.2 Interpretation of the sandwich corrosion test results is based on a comparison of the appearance of faying surfaces of three sets of coupons. One set of test coupons is exposed with reagent water only in the faying surfaces, to establish the baseline (controls) against which the panels exposed to the test material are compared. Disregard corrosion at cut edges of the test coupons. 5.3 The relative corrosion severity rating system is provided in order to allow a numerical classification of the test results and to eliminate the necessity for elaborate weight loss measurements. Pitting corrosion, which is rated 4—extensive (severe) corrosion, may involve only a negligible weight loss. 5.4 Relative corrosion severity rating system: Appearance/Corrosion: 0—No visible corrosion and no discoloration present 1—Very slight corrosion or very slight discoloration, and/or up to 5 % of area A corroded 2—Discoloration and/or up to 10 % of area A corroded 3—Discoloration and/or up to 25 % of area A corroded 4—Discoloration and/or more than 25 % of area A corroded, and/or pitting present (A) ”Area” refers to area under the filter paper, or if no filter paper is used, the area where the test material was applied.