首页 馆藏资源 舆情信息 标准服务 科研活动 关于我们
历史 ASTM D1732-03(2008)
到馆提醒
收藏跟踪
购买正版
Standard Practices for Preparation of Magnesium Alloy Surfaces for Painting 制备镁合金表面的标准做法
发布日期: 2008-04-01
1.1这些实践涵盖了两类镁合金表面涂装前处理,如下所示: I类 — 化学处理。 II类 — 阳极处理。 总的来说,后一种治疗方法对这两类人更具保护性。机械(研磨)处理、溶剂清洗、碱性溶液处理和酸洗不会产生保护性转化涂层,仅适用于在轻度腐蚀(室内)暴露下暴露的金属。当需要高度防腐和油漆附着力时,如在许多室外环境中,通过上述转换之一进行表面处理- 涂层等级是必要的。不推荐使用基于六价铬的方法,因为六价铬是一种已知的致癌物。 笔记 1— 涂层测试 — 通常需要对涂层进行质量控制测试,这些测试通常包括暴露在盐雾、湿度或自然环境中(有油漆或无油漆),以及在固定时间间隔后评估破裂程度的适当程序。建议尽可能使用高纯度材料(例如AZ31A合金)进行涂层的质量控制测试,其固有腐蚀速率在批次之间相对一致,并且应采取预防措施,在涂覆涂层之前清除表面污染。 应通过酸洗至至少0.001英寸的深度来清除此类污染。(25 μ m) 每侧。 1.2 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和健康实践,并确定监管限制的适用性。 (见注释11。)
1.1 These practices cover two classes of treatment for preparation of magnesium alloy surfaces for painting, as follows: Class I — Chemical Treatments. Class II — Anodic Treatments. In general, the latter treatments are the more protective of the two classes. Mechanical (abrasive) treatments, solvent cleaning, alkaline solution treatments, and acid pickles not resulting in protective conversion coatings are suitable preliminary treatments only for metal to be exposed under mildly corrosive (indoor) exposures. When a high degree of corrosion protection and paint adhesion are desired, as in many outdoor environments, surface preparation by one of the above conversion-coat classes is necessary. The hexavalent chromium based methods given are not recommended as hexavalent chromium is a known carcinogen. Note 1— Testing of Coatings — Quality control tests of coatings are frequently desirable, and these generally consist of exposures, with or without paint, to salt spray, humidity, or natural environments, with suitable procedures for assessing the degree of breakdown suffered after fixed time intervals. It is recommended that quality control tests of coatings shall be made as far as possible with high-purity material (for example AZ31A alloy), the inherent corrosion rate of which is relatively consistent from batch to batch) and that precautions shall be taken to remove surface contamination before coatings are applied. Such contamination shall be removed by acid pickling to a depth of at least 0.001 in. (25 μ m) per side. 1.2 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 and health practices and determine the applicability of regulatory limitations prior to use. (See Note 11.)
分类信息
关联关系
研制信息
归口单位: B08.07
相似标准/计划/法规