Purity of copper

Standards

Testing

Purity of copper is defined by the contents of the basic substance and expressed in percentages defined as a difference between 100 % and the sum of supervised impurities. Supervised impurities - the list of elements are measured in the sample for definition of purity. As a rule, it is necessary to define not only the list of controlled elements, but also their limiting contents. Various elements differently influence characteristics of copper. That is, it is important not only the sum of impurity, but also their "portrait" (how many and what element).

Supervised impurities can be defined by various standards or specifications. The most known standards are GOST 859-2001 (Russia), ASTM B170 (USA), ISO (the International Organization of Standards: the European union and others). Under these standards it is the extremely complex to reach the stable guaranteed result above ~ 99,998 % (at correct calculation), at least, for one work cycle. Depending on a problem of the customer and opportunities of the manufacturer the controled  impurities can also will be defined by other specifications.

RESULT of testing is varied depending on supervised impurities,  from methods of the analysis, the equipment and qualification.  Result depends on  LABORATORY. Purity does not vary. Our material was tested at various leading laboratories (in Russia, the USA, China) by methods of LMS, AES, SSMS and GDMS. Not all methods, the equipment and qualification allow to measure  chemical purity of copper equally. Especially it concerns purity of 5N+ and above. Some methods and laboratories cannot measure certain elements or test exactly, like they are real.

CHEMICAL  PURITY  and   TRACE  IMPURITIES

Analysis of our Copper requires very good preparation of equipment appropriate to this level of purity, in super-quality and super-pure materials and instruments (chemical substances, cutters and other work tools) for preparation of the copper sample for analysis and  the highest qualification level of the laboratory personnel. According to GOST 859-2001,  ASTM B170:

Grade  \

Cu:

Cu + Ag:

Cu + 0:

Cu:

Cu + Ag:

Cu + 0:

New (2018)

5N2 - 5N3

5N2 - 5N3

5N4 - 5N5

5N7 - 7N+

5N7 - 7N+

6N- 7N+

5N - 5N3

5N2 - 5N3

5N2 - 5N5

5N5 - 6N+

5N6 - 6N+

5N6 - 6N+

LMS+AES (Institute of Inorganic Chemistry of the Siberian Branch of the Russian Academy of Sciences, Russia) are limited by methods and the equipment: excluding Fe and Ag, all impurities are always is Detection Limit of methods and the equipment, including metals and metalloids not entering into  ASTM B170 (limits are <0.08 - <0.2 depending on an element). Oxygen is measured and counted "< 2 ppm" as LMS Detection Limit of the current equipment. In reality, oxygen can be <0.05 - <0.1 - <1ppm.  Our technology is able to make it. It is necessary to find and use the equipment  capable of  such measuring.  Needed  Detection Limit  is <0.01ppm. SSMS+GDMS have deeper limits of detection, but has complexities with measurement of oxygen, sulfur and with measuring exactly sometimes of some other impurities like they are in a reality. Quality of a product demands very high level of a laboratory and the suitable methods. Limits " <x - <0.00x " were subtracted from 100 % at calculation of purity as corresponding quantity of impurities.

Sometimes some elements are not considered at definition of purity and/or calculation of purity is not correctly spent, and such Cu can be presented  as 5N-6N and above. Probably, in some tasks is admissible to not consider some elements, but these moments should be distinguished. Cu 5N-9N measured under the reduced list of elements or with dodges of calculation  can have characteristics worse than even 4N according ASTM B170.

Wishes of the customer to additional restrictions of impurities besides our specified current standards can be considered, if it is possible to fulfil it.  Own technology, an opportunity of achievement of the specified parameters.

Information about Cu 5-9N :