1.1这些实践包括以下五项测试: 1.1.1 练习A -奥氏体不锈钢蚀刻结构分类的草酸蚀刻试验（第3节至第7节，包括在内）， 1.1.2 实践B -检测奥氏体不锈钢晶间腐蚀敏感性的硫酸铁-硫酸试验（第8节至第14节，包括在内）， 1.1.3 实践C -检测奥氏体不锈钢晶间腐蚀敏感性的硝酸试验（第15至21节，包括在内）， 1.1.4 练习E -检测奥氏体不锈钢晶间腐蚀敏感性的硫酸铜-硫酸铜试验（第22至31节，包括在内），以及 1.1.5 实践F -硫酸铜-50%硫酸试验检测钼晶间腐蚀敏感性- 轴承铸造奥氏体不锈钢（第32至38节，包括在内）。 1.2以下因素制约着这些实践的应用: 1.2.1在所有六个试验中，都很容易检测到与碳化铬沉淀有关的晶间腐蚀敏感性。 1.2.2变形铬镍钼钢中的Sigma相可能在微观结构中可见，也可能不可见，只能在硝酸中导致高腐蚀速率。 1.2.3钛或铌稳定合金和铸造含钼不锈钢合金中的Sigma相在微观结构中可能可见或不可见，可导致硝酸和硫酸铁-硫酸溶液中的高腐蚀速率。 1.3草酸蚀刻试验是一种通过简单蚀刻快速识别某些不锈钢等级的试样的方法，这些不锈钢等级基本上不易受到与碳化铬沉淀物相关的晶间侵蚀。 在某些腐蚀试验中，这些试样的腐蚀速率较低，因此可以从试验中消除（筛选）为“可接受” 1.4硫酸铁-硫酸试验、硫酸铜-硫酸铜-50%试验和硝酸试验基于失重测定，因此，提供了评估样本相对性能的定量测量。相反，硫酸铜-16%硫酸试验基于弯曲试样的目视检查，因此，仅将试样分为可接受或不可接受。 1.5在大多数情况下，24小时硫酸铜-16%硫酸试验或120小时硫酸铁-硫酸试验，结合草酸蚀刻试验，将在最短时间内提供所需信息。 附表中列出的所有不锈钢等级可在这些筛选和腐蚀试验组合中进行评估，但含钼等级（例如316、316L、317和317L）的试样除外，这些试样代表拟在硝酸环境中使用的钢。 1.6 240小时硝酸试验必须适用于拟在硝酸中使用的稳定和含钼牌号，以及所有可能在硝酸中受到端粒腐蚀的不锈钢牌号。 1.7表1中仅列出了草酸蚀刻试验的应用数据及其在各种定量评估试验中的性能数据。 1.8参考文献（1）中公布了根据这些实践评估的各种类型不锈钢的广泛试验结果。 1.9以国际单位制表示的数值应视为标准值。英寸-磅当量在括号中，可能是近似值。 1.10 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和健康实践，并确定监管限制的适用性。 （具体预防说明见5.6、11.1.1、11.1.9和35.1。）

1.1 These practices cover the following five tests: 1.1.1 Practice A — Oxalic Acid Etch Test for Classification of Etch Structures of Austenitic Stainless Steels (Sections 3 to 7, inclusive), 1.1.2 Practice B —Ferric Sulfate-Sulfuric Acid Test for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels (Sections 8 to 14, inclusive), 1.1.3 Practice C —Nitric Acid Test for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels (Sections 15 to 21, inclusive), 1.1.4 Practice E —Copper-Copper Sulfate-Sulfuric Acid Test for Detecting Susceptibility to Intergranular Attack in Austenitic Stainless Steels (Sections 22 to 31, inclusive), and 1.1.5 Practice F —Copper-Copper Sulfate-50% Sulfuric Acid Test for Detecting Susceptibility to Intergranular Attack in Molybdenum-Bearing Cast Austenitic Stainless Steels (Sections 32 to 38, inclusive). 1.2 The following factors govern the application of these practices: 1.2.1 Susceptibility to intergranular attack associated with the precipitation of chromium carbides is readily detected in all six tests. 1.2.2 Sigma phase in wrought chromium-nickel-molybdenum steels, which may or may not be visible in the microstructure, can result in high corrosion rates only in nitric acid. 1.2.3 Sigma phase in titanium or columbium stabilized alloys and cast molybdenum bearing stainless alloys, which may or may not be visible in the microstructure, can result in high corrosion rates in both the nitric acid and ferric sulfate-sulfuric acid solutions. 1.3 The oxalic acid etch test is a rapid method of identifying, by simple etching, those specimens of certain stainless steel grades which are essentially free of susceptibility to intergranular attack associated with chromium carbide precipitates. These specimens will have low corrosion rates in certain corrosion tests and therefore can be eliminated (screened) from testing as "acceptable." 1.4 The ferric sulfate-sulfuric acid test, the copper-copper sulfate-50% sulfuric acid test, and the nitric acid test are based on weight loss determinations and, thus, provide a quantitative measure of the relative performance of specimens evaluated. In contrast, the copper-copper sulfate-16% sulfuric acid test is based on visual examination of bend specimens and, therefore, classifies the specimens only as acceptable or non-acceptable. 1.5 In most cases either the 24-h copper-copper sulfate-16% sulfuric acid test or the 120-h ferric sulfate-sulfuric acid test, combined with the oxalic acid etch test, will provide the required information in the shortest time. All stainless grades listed in the accompanying table may be evaluated in these combinations of screening and corrosion tests, except those specimens of molybdenum-bearing grades (for example 316, 316L, 317, and 317L), which represent steel intended for use in nitric acid environments. 1.6 The 240-h nitric acid test must be applied to stabilized and molybdenum-bearing grades intended for service in nitric acid and to all stainless steel grades which might be subject to end grain corrosion in nitric acid service. 1.7 Only those stainless steel grades are listed in Table 1 for which data on the application of the oxalic acid etch test and on their performance in various quantitative evaluation tests are available. 1.8 Extensive test results on various types of stainless steels evaluated by these practices have been published in Ref (1). 1.9 The values stated in SI units are to be regarded as standard. The inch-pound equivalents are in parentheses and may be approximate. 1.10 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. (Specific precautionary statements are given in 5.6, 11.1.1, 11.1.9, and 35.1.)