1.1本指南涵盖了计算机化材料性能数据库中金属和合金的识别。它建立了用于唯一识别和描述特定金属或合金样品以及识别给定金属或合金的属性的基本和理想数据元素。 1.1.1本指南不一定提供足够的数据元素来描述焊接金属、金属基复合材料或连接金属。 1.1.2本文中确定的数据元素并非与每个金属或合金组都密切相关。 1.1.3根据特定于该金属或合金组的条件或应用，也可在给定金属或合金组内应用不同的数据元素集。此外，在特定金属或合金组内，可以使用不同的数据元素集来识别特定的材料条件。 1.1.4本指南末尾显示了关于推荐数据元素的表1和关于特定数据元素值的表2-17。 1.2本指南中的一些数据元素可能对其他目的有用。然而，本指南不试图记录用于任何目的的必要和可取的数据元素，除非在计算机化材料特性数据库中识别金属和合金。其他用途，如材料生产、材料采购和材料加工，每种用途可能有不同于本指南所涵盖的材料数据报告要求。一个具体的例子是合同要求的材料性能测试系列报告。此类报告可能不包含对特定计算机化数据库至关重要的所有数据元素；相反，本指南可能不包含合同测试报告所需的所有数据元素。 ====意义和用途====== 本指南描述了在计算机化数据库中唯一识别金属或合金所必需的信息类型。其目的是便于使用计算机对信息进行标准化存储和检索，并允许对不同来源的数据进行有意义的比较。 许多金属和合金的编号系统是根据其化学成分开发的。为了缩小其描述范围，还发展了单独的系统来描述金属和合金的热机械条件。将这些复杂、具有历史意义和重叠的识别系统分离为逻辑数据元素是在计算机化数据库中识别金属和合金的挑战。 本指南旨在为材料特性数据库的设计者和建造者提供一个共同的起点。 本指南通常根据数据元素确定数据库的内容，但不推荐任何特定的逻辑或物理数据库设计。数据库生成器在设计数据库模式时具有相当大的灵活性，本指南旨在支持这种灵活性。 众所周知，材料属性数据库将针对不同级别的材料信息和不同目的进行设计。例如，由行业贸易组织开发的数据库可能只识别通常代表特定金属或合金的典型特性，而不是在特定样本上测量的实际值。另一方面，企业可能希望管理其采购的特定批次的数据，甚至管理批次中特定零件或样品的属性。因此，本指南中确定的一些数据元素可能不适用于每个数据库实例。 在特定数据库中实现的材料识别程度取决于其特定用途。单个组织可能在其数据库中包含大量详细信息。出于商业和其他考虑，一些组织使用的通用数据库中可能包含较少的细节。由于金属和合金种类繁多，技术也在不断变化，因此不应将建议视为排除了用于材料识别的其他数据元素。如果要记录用于识别材料的其他详细信息，则应扩展推荐的数据元素。 许多数据元素对于任何数据库都是必不可少的，并且需要存在于数据库中。如果用户需要有足够的信息来解释数据，并确信能够比较不同来源材料的数据集，则数据元素被认为是必不可少的。 未能完成基本数据元素可能导致记录在数据库或数据交换中无法使用。本质是指记录数据的质量或完整性，不一定具有与数据库结构相关的直接含义。在某些情况下，已识别的数据元素可能包含在特定数据库中，而不明确包括仅用于基本数据元素的字段。此外，数据库模式可能要求其他数据字段不为null，以保持数据记录完整性或实现强制数据关系。这些附加字段超出了本指南的范围。最后，还需要注意的是，本指南中确定为关键的数据元素可能与为有限范围的特定应用创建的数据库无关。 本指南提供了数据元素的列表，并不打算定义在数据库的逻辑或物理模型中使用的数据元素的任何单一组织。 数据元素列表按组标题划分，仅供讨论之用。组标题不是为了识别数据库模型的规范化；这由数据库设计者决定。 可能需要重复本指南中列出的许多数据元素，以识别哪怕是单个材料。根据数据库的用途或设计，可能适合将数据库设计为启用其他可重复数据元素。数据库应该如何为给定的数据元素容纳多个值是留给数据库设计者的另一个问题。

1.1 This guide covers the identification of metals and alloys in computerized material property databases. It establishes essential and desirable data elements that serve to uniquely identify and describe a particular metal or alloy sample as well as properties that identify a given metal or alloy in general. 1.1.1 This guide does not necessarily provide sufficient data elements to describe weld metal, metal matrix composites, or joined metals. 1.1.2 The data element identified herein are not all germane to every metal or alloy group. 1.1.3 Different sets of data elements may also be applied within a given metal or alloy group depending on conditions or applications specific to that metal or alloy group. Further, within a particular metal or alloy group, different sets of data elements may be used to identify specific material conditions. 1.1.4 Table 1 on Recommended Data Elements and Tables 2-17 on values for specific data elements appear at the end of this guide. 1.2 Some of the data elements in this guide may be useful for other purposes. However, this guide does not attempt to document the essential and desirable data element for any purpose except for the identification of metals and alloys in computerized material property databases. Other purposes, such as material production, material procurement, and material processing, each may have different material data reporting requirements distinct from those covered in this guide. A specific example is the contractually required report for a material property testing series. Such a report may not contain all the data elements considered essential for a specific computerized database; conversely, this guide may not contain all the data elements considered essential for a contracted test report. ====== Significance And Use ====== This guide describes the types of information that are indispensable for uniquely identifying a metal or alloy in a computerized database. The purpose is to facilitate standardized storage and retrieval of the information with a computer, and allow meaningful comparison of data from different sources. Many numbering systems for metals and alloys have been developed which are based on their chemical compositions. Separate systems have also evolved to describe the thermomechanical condition of metals and alloys in order to narrow their description. It is the separation into logical data elements from these complex, historically significant, and overlapping systems of identification that is the challenge in the identification of metals and alloys within computerized databases. This guide is intended to provide a common starting point for designers and builders of materials property databases. This guide generally identifies the contents of the database in terms of data elements, but does not recommend any particular logical or physical database design. A database builder has considerable flexibility in designing a database schema, and it is intended that this guide support that flexibility. It is recognized that material property databases will be designed for different levels of material information and for different purposes. For example, a database developed by an industry trade group might only identify typical properties generally representative of those for a particular metal or alloy, and not actual values measured on a specific sample. On the other hand, a business might desire to manage data on specific lots it procures, or even properties of a specific piece or sample from a lot. Consequently, some of the data elements identified in this guide might not be applicable in every database instance. The extent of material identification implemented in a particular database depends on its specific purpose. A single organization may include substantial detail in its database. Less detail may be included in a common database used by several organizations because of commercial and other considerations. Since metals and alloys are diverse and the technologies are always changing, recommendations should not be regarded as exclusive of additional data elements for material identification. The recommended data elements should be expanded if additional detailed information which serves to identify materials is to be recorded. A number of data elements are considered essential to any database and need to exist in the database. Data elements are considered essential if they are required for users to have sufficient information to interpret the data and be confident of their ability to compare sets of data for materials from different sources. Failure to complete an essential data element may render the record unusable in a database or in data exchange. Essential refers to the quality or completeness of recorded data, and does not necessarily have direct meaning relative to database structure. In some cases, the identified data element might be accommodated within a particular database without explicitly including a field just for the essential data element. Additionally, a database schema may require additional data fields to be not null to maintain data record integrity or to implement a mandatory data relationship. These additional fields are beyond the scope of this guide. Finally, it is also noted that a data element identified as essential in this guide might not be relevant for a database created for a specific application of limited scope. This guide presents a listing of the data elements and does not intend to define any single organization of the data elements to be used in either a logical or physical model for the database. The data element lists are divided by group headings for discussion purposes only. The group headings are not intended to identify normalization of the database model; this is left to the database designer. Numerous data elements listed in this guide may need to be repeated to identify even a single material. Depending on the database purpose or design, it may be appropriate to design the database to enable additional repeatable data elements. How the database should accommodate multiple values for a given data element is another question left to the database designer.