ISO 7625:2006规定了从待分析材料的一个或多个烧结部分制备样品的方法，以测定游离碳或总碳含量。结合碳被确定为总碳和游离碳之间的差异。本标准涵盖了根据ISO 437通过化学方法测定碳的样品制备，即在氧气中燃烧和测量产生的二氧化碳。它不包括通过物理方法（如金相或光谱学）测定碳的样品制备。

ISO 7625:2006 specifies methods for preparing a sample from one or more sintered parts of materials to be analysed for free or total carbon content. Combined carbon is determined as the difference between total and free carbon. This standard covers the preparation of samples for the determination of carbon by a chemical method, i.e. combustion in oxygen and measurement of the carbon dioxide produced, in accordance with ISO 437. It does not cover the preparation of samples for carbon determination by physical methods, such as metallography or spectroscopy.