金属和合金的腐蚀 在氨蒸气中测定铜及铜锌合金的应力腐蚀开裂抵抗力

[中文适用范围]： 1 适用范围 本文件规定了在氨蒸气中测定铜及铜锌合金抗应力腐蚀开裂（SCC）性能的方法。本文件涵盖了取样方法、试样类型、加载程序、环境类型以及结果的解释。本文件旨在根据铜及铜锌合金的化学成分和制造方法，测定其抗SCC性能。本文件适用于以产品和零部件形式存在的加工铜及铜锌合金。本文件可用于对含有氨的气氛中材料的性能进行排序，并选择候选材料。然而，本测试的结果不应被视为合金质量的绝对标准。本文件规定了在与氨水溶液共存的氨蒸气中暴露试样的方法，并规定了环境条件和测试程序。本文件规定了两种加载方法：在总应变恒定条件下加载；在恒定载荷条件下加载。本文件不涵盖慢应变速率测试方法以及通过该方法确定最大允许应力的内容。 [外文原描述]： This document specifies a method for the determination of resistance to stress corrosion cracking (SCC) of copper and copper-zinc alloys in ammonia vapour. This document covers the method of sampling, the types of specimens, the loading procedure, the type of environment and the interpretation of results. This document is aimed at determining resistance to SCC as a function of the chemical composition, the method of manufacture of copper and copper-zinc alloys. This document applies to wrought copper and copper-zinc alloys in the form of products and parts. This document can be used to rank materials performance and select candidate materials under atmospheres containing ammonia. However, the results of this test should not be considered as an absolute criterion for the quality of alloys. This document specifies a method for exposing test specimens in ammonia vapour coexisting with an aqueous ammonia solution and specifies the environmental conditions and test procedures. This document specifies two methods of loading: under constant total strain; under constant load. It does not cover slow strain rate test methods and determination of maximum admissible stress by the method of permanent deformation for copper and copper-zinc alloys, although an effort is now being made to apply such methods to these alloys (see ISO 7539-7).