1.1 本规程涵盖了挤压型材或模制SP零件中残余应力的评估。残余应力的存在和相对大小通过浸入一个或多个系列化学试剂中时试样零件的开裂来表示。之前使用环境应力开裂（ESC）技术校准了指定的化学试剂，以在指定的应力水平下导致砜塑料（SP）开裂。 1.2 本规程仅适用于以下熔体流动速率所示的高分子量的未填充注塑和挤出级材料:PSU 9 g/10 min，max.，PESU 30 g/10 m，max，和PPSU 25 g/10 min，max。较低分子量（较高熔体流动）的材料将在低于中所示的应力水平下开裂 表1- 3. . （见规范 D6394 对于熔体流动速率条件。） 表1 PSU残余应力测试用液体试剂 混合物 混合物成分 临界应力，MPa（psi） %按体积计算的乙醇 %按体积计乙酸乙酯 1. 50 50 15.2 (2200) 2. 43 57 12.1 (1750) 3. 37 63 9.0 (1300) 4. 25 75 5.5 (800) 表2 PESU残余应力测试用液体试剂 混合物 混合物成分 临界应力，MPa（psi） %按体积计算的乙醇 %按体积计MEK 1. 50 50 17.9 (2600) 2. 40 60 10.3 (1500) 3. 20 80 6.9 (1000) 4. 0 100 5.9 (850) 表3 PPSU残余应力测试用液体试剂 混合物 混合物成分 临界应力，MPa（psi） %按体积计算的乙醇 %按体积计MEK 1. 50 50 22.8 (3300) 2. 25 75 13.8 (2000) 3. 10 90 9.0 (1300) 4. 0 100 8.0 (1150) 1.3 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。 注1: 本标准没有已知的ISO等效标准。 1.4 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。 1.5 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 热塑性模塑件包含由于模塑件厚度的不同冷却速率而产生的残余应力。由于应力松弛，已发现残余应力随成型后的时间而变化。零件中存在的残余应力水平会影响许多零件性能参数以及零件故障。 残余应力会导致收缩、翘曲和环境应力抗裂性下降。本规程估计了由一系列砜塑料（SP）即聚砜（PSU）、聚醚砜（PESU）和聚苯砜（PPSU）材料生产的零件中残余应力的相对大小。 5.2 通过本规程测定残余应力的结果与零件性能之间未建立直接相关性。因此，不建议将本规程作为其他试验的替代品，也不建议将其用于零件的采购规范中。尽管存在这一限制，但这种做法在指示残余应力的存在和塑料零件的相对质量方面确实产生了有价值的信息。 5.3 残余应力不容易计算，因此采用实验方法（如本实践）来估计残余应力很重要。 5.4 对于希望评估SP零件中残余应力的挤出机和注塑机来说，这种做法很有用。这可以通过在浸入一种或多种化学试剂后进行目视检查来完成，以评估是否发生开裂。成型或挤压后应力会松弛。因此，如果比较零件，则必须在处理后相同的时间和条件下浸入测试介质和进行目视检查。注意零件历史中的差异很重要。因此，该技术适合作为塑料加工质量的指标。 5.5 该方法主要用于指示表面附近的残余应力。

1.1 This practice covers the evaluation of residual stresses in extruded profile or molded SP parts. The presence and relative magnitude of residual stresses are indicated by the crazing of the specimen part upon immersion in one or more of a series of chemical reagents. The specified chemical reagents were previously calibrated by use of Environmental Stress Cracking (ESC) techniques to cause crazing in sulfone plastics (SP) at specified stress levels. 1.2 This practice applies only to unfilled injection molding and extrusion grade materials of high molecular weight as indicated by the following melt flow rates: PSU 9 g/10 min, max., PESU 30 g/10 m, max, and PPSU 25 g/10 min, max. Lower molecular weight (higher melt flow) materials will craze at lower stress levels than indicated in Tables 1- 3 . (See Specification D6394 for melt flow rate conditions.) TABLE 1 Liquid Reagents for Residual Stress Test for PSU Mixture Mixture Composition Critical Stress, MPa (psi) % by volume Ethanol % by volume Ethyl Acetate 1 50 50 15.2 (2200) 2 43 57 12.1 (1750) 3 37 63 9.0 (1300) 4 25 75 5.5 (800) TABLE 2 Liquid Reagents for Residual Stress Test for PESU Mixture Mixture Composition Critical Stress, MPa (psi) % by volume Ethanol % by volume MEK 1 50 50 17.9 (2600) 2 40 60 10.3 (1500) 3 20 80 6.9 (1000) 4 0 100 5.9 (850) TABLE 3 Liquid Reagents for Residual Stress Test for PPSU Mixture Mixture Composition Critical Stress, MPa (psi) % by volume Ethanol % by volume MEK 1 50 50 22.8 (3300) 2 25 75 13.8 (2000) 3 10 90 9.0 (1300) 4 0 100 8.0 (1150) 1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. Note 1: There is no known ISO equivalent for this standard. 1.4 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. 1.5 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 Thermoplastic moldings contain residual stresses due to differential cooling rates through the thickness of the molding. Changes in residual stress have been found to occur with time after molding due to stress relaxation. Many part performance parameters as well as part failures are affected by the level of residual stress present in a part. Residual stresses cause shrinkage, warpage, and a decrease in environmental stress crack resistance. This practice estimates the relative magnitude of residual stresses in parts produced from the series of sulfone plastics (SP), namely polysulfone (PSU), polyethersulfone (PESU), and polyphenylsulfone (PPSU) materials. 5.2 No direct correlation has been established between the results of the determination of residual stresses by this practice and part performance properties. For this reason, this practice is not recommended as a substitute for other tests, nor is it intended for use in purchasing specifications for parts. Despite this limitation, this practice does yield information of value in indicating the presence of residual stresses and the relative quality of plastic parts. 5.3 Residual stresses cannot be easily calculated, hence it is important to have an experimental method, such as this practice, to estimate residual stresses. 5.4 This practice is useful for extruders and molders who wish to evaluate residual stresses in SP parts. This can be accomplished by visual examination after immersion in one or more chemical reagents to evaluate whether or not cracking occurs. Stresses will relax after molding or extrusion. Accordingly, both immersion in the test medium and visual examination must be made at identical times and conditions after processing, if comparing parts. It is important to note the differences in part history. Thus, this technique is suitable as an indication for quality of plastic processing. 5.5 The practice is useful primarily for indicating residual stresses near the surface.