Copper Industry – Pure Cu and Alloys

Copper – Testing requirements

The Copper industry spans a vast range of applications. From OFE (Oxygen-free Electronic), OFC (Oxygen-free) and ETP (Electrolytic Tough Pitch) grades that need 99.95+% purity to high alloys like Brass and Cupro-Nickel, there is a vast array of testing requirements that an OES caters to. From ensuring full testing of the purity of Copper to helping drive dramatic cost savings for alloy makers, an OES is an invaluable aid for those in the Copper industry.

Pure Copper – ETP, OFC and OFE

Pure Copper is typically classed as being a minimum of 99.90% Copper. That though, is merely the tip of the iceberg, with requirements being highly specific for various grades and types of Pure Copper. For instance, all of ETP, OFC and OFE are classified as Pure Copper, but have dramatically different allowable levels of Oxygen. Similarly, allowable impurity levels in a grade are specified not only at an element-level, but also at a group-level for groups of elements. Most often, the combined impurity level is far below the summation of individual “max.” levels. This makes it critical for the OES to have analytical capabilities to cover as many elements as possible and single- or sub-ppm detection limits for each element to ensure that there is no ambiguity around the acceptability of the material.

Oxygen analysis

Oxygen of course is an absolutely critical element for all makers of Pure Copper. Across all of OFE, OFC and ETP, Oxygen is an element that is essential to quantify in order to be in conformance with grade requirements:

• OFE must have ≤5 ppm O
• OFC must have ≤10 ppm O
• ETP grades typically range from 200-400 ppm (this is the typical range, though newer grades may go as low as 50 ppm O and some grades may range above this too

For any manufacturer of Pure Copper therefore, Oxygen is as close to being an essential element as it gets!

Detection limits – lower the better

Pure Copper requirements are often far more stringent than a cursory look at the data sheet would reveal. For example, in most conductor requirements and for Cathodic Copper, Bi, Se and Te have individual “max” levels of 2, 2 and 1 ppm respectively, but total allowable content across all three is typically just 3 ppm instead of 5 ppm. Similarly, individual “max” levels of specified trace elements could add up to 84-90 ppm, but the total allowable level is just 65 ppm.

Here again, there is another added complexity. Limits are specified for only 14-15 elements for which ranges are specified, but alongside this, the overall purity level is specified too – and that encompasses a lot more elements; indeed, a good mid-range or high-end OES analyses over 30 elements!

All of this makes it critical to ensure that the OES used for analysis of Pure Copper has detection limits that are exceedingly low.

Copper Alloys

Alloy makers don’t focus on the overall purity of Copper, but on ensuring that all ranges are met for alloying elements and that all trace and tramp elements are maintained under the specified “max” level, which is typically less stringent than for Pure Copper. That said, this does not lessen the impact an OES makes for alloy makers in any manner. Indeed, if used well, an OES can add as much – or even more – value for alloy makers.

For every alloy, key elements like Zinc, Titanium, Nickel, Lead etc., have their target ranges. The elemental compositions must be within these ranges for the product to be acceptable. The firm therefore has the choice of whether to work at the absolute margin of these limits or to build safety buffers. The idea of safety buffers is appealing, but this comes at a cost! Staying above the min. level of expensive alloying elements like Ni (Nickel), Cu (Copper), Ti (Titanium) etc. would mean significantly higher raw material costs, without at the same time, resulting in higher revenue realization.

Hence, the best practice for profit-optimization is to be close to the minimum level specified – ensuring a safety margin, but also minimizing the material cost as much as possible. This requires knowing the actual concentration of these elements in the melt before casting which is where a spectrometer comes in. Process controls do not give full control – leading to users keeping a wide margin for error. An OES solves this issue. Using sampling moulds, a sample can be taken from the melt and tested within seconds, giving highly accurate analysis while the metal is still in the melt. If analysis results show that the melt is of the correct mix, then it may be poured. If not, then adjustments can be made rapidly and without going through any rejection / re-melting process. While the OES enables the firm to work closer to the lower limits of the ranges, the target concentration has to be kept within the Standard Deviation (SD) or Precision of the spectrometer at that particular elemental concentration level! A logical corollary is that for obtaining the best savings, the OES should not only be highly accurate (represent correct concentration) but also offer ultra-high precision even at low concentration levels. The higher the resolution of the OES, the better is its capability to support work closer to the margins, regardless of the limits and ranges involved.

Metal Power OES for the Copper Industry

With the world’s widest range of Laboratory and Mobile OES – in terms of applications as well as budgets, Metal Power offers solutions for every need across the value chain

High-end models – for high-purity applications:

The Metavision-10008X and the Metavision-1008i3 offer solutions for Copper companies seeking high-resolution, low detection limits and high-end features. Indeed, the Metavision-10008X, features virtually every feature required while also making it possible to analyse – quite literally – every element on the periodic table – all within a span of just 10 seconds! The Metavision-10008X and the Metavision-1008i³ both offer Oxygen analysis (1 ppm and 10 ppm limits respectively) as well! This makes these models absolutely ideal for those users that are focused on OFE, OF and ETP copper.

For OFE Copper, the Metavision-10008X is the go-to solution as its capabilities, particularly on critical elements like O, Se, Te, Bi etc. were designed specifically keeping in mind the needs of this segment! The Metavision-10008X offers 0.1-0.5 ppm LODs for Se, Te and Bi and 1 ppm for Oxygen, and delivers highly accurate and precise analysis of Pure Copper beyond 99.997% purity (including O).

For OFC, both the Metavision-10008X and the Metavision-1008i³ would meet requirements with the latter offering O down to 10 ppm and overall purity of 99.992+% (including O). Both the Metavision-10008X and the Metavision-1008i³ meet ETP Copper needs comfortably – and grade- specific requirements would determine the model of choice.

Workhorse models for alloy-makers

For those that do not work at the highest levels of purity and therefore do not require the lowest detection limits or features such as Oxygen analysis, Metal Power has two best-selling models – the Metavision-1008i that meet all the analytical needs for alloy makers while also offering great economy along with exceptional accuracy, precision and stability.

Economical solutions for entry-level

MOSS – Metal Power’s entry-level spectrometer offers the ideal solution for a wide range of copper alloy industries. For all manner of firms across various alloys such as brasses and bronzes, MOSS offers a truly breathtaking value proposition. The most compact and most economical OES in the world, MOSS still offer capabilities across 21 elements in Copper including Ag, Cd, Cr and Be! It is also fully scalable (including at-site)!

Mobile Solutions – Testing on Wheels

Copper firms as well as scrap dealers also have extensive need for mobile testing solutions; these OES are needed for multifarious tasks including:

• PMI (Positive Material Identification)
• Sorting (typically needed in large yards)
• Testing large parts that can’t be sampled for Laboratory testing
• Testing materials at Entry gates

The Metavision-108M and the Metavision-1008M³ offer ideal solutions for such needs and are available with a range of probes – arc, spark, UV and various combined probe options too.

Unique Metal Power solutions for the Copper industry

Metal Power has developed some truly unique and ground-breaking solutions which have key upsides for the Copper industry to tremendously enhance the value our spectrometers deliver:

Fine wire analysis

Our patented solution analyses (fully quantitatively) fine wires that as thin as 0.1 mm in diameter! This solution is particularly relevant in the Copper industry – where fine wires are routinely made / tested.

Foil analysis

For foils, we offer analysis of foils down to 20-micron (0.02 mm) thickness; a patented solution, this offers phenomenal value addition.

Direct-base analysis

It is well known that OES determine the base element by analyzing the rest of the elements and then getting the base element concentration by subtracting the total of the rest of the elements from 100%. This is fraught with the danger of getting higher base element values when all elements are not analyzed. When analyzing Copper Alloys, Metal Power analyzes the base element, that is Copper, directly.

Master Alloys analysis

Copper foundries use master alloys with extremely high levels of alloying elements. As standard OES are not calibrated to such high levels, most users don’t analyse these and rely on accepting the supplier’s certificate and trying to “manage” the melt. Similarly, those that make the master alloys also struggle to actually control the melt as they can’t assess the levels optimally. MPA has developed solutions and offers customized programs that enable customers to rapidly and accurately analyse even their master alloys! Customer experience shows that such analyses can save money and time – while they also help in quantitative vendor quality evaluations and actual pricing for Master Alloys

For more information, product details and application-specific information,
please contact us at sales@metalpower.net.