In 2014 Cathodic Anodes Australasia (CAA) purchased the benchtop optical emission spectrometer FOUNDRY-MASTER Xpert from Oxford Instruments. Here we examine their experience and what drove their decision to purchase the instrument.
Russell Northey is a Metallurgist at CAA and was the decision maker behind instrument purchase and commissioning.
I have recently had the privilege of commissioning a new OES (Optical Emission Spectrometer) for CAA and have used it for over two years... I believe the Oxford Instruments FOUNDRYMASTER Xpert was the best possible choice for our process requirements and working with it has been a very positive experience.
Russell Northey, Metallurgist, CAA
Initial situation
Decision Process
Cathodic Anodes Australasia (CAA) manufacture Galvanic (Sacrificial) Anodes for Cathodic Protection, and in 2014 they needed to replace a 30 year old OES instrument that was used for QA/QC. Russell has the task of finding the correct solution for current processes that would also be future proof against obsolescence.
We had two goals to fulfill – obtain an instrument to give us a possible market edge and avoid the heartache of a breakdown that was not possible to repair. The instrument we were using was a retro-fit in 2001 of a mid-80’s instrument and was nearing 30 years old. Spare parts were becoming very rare to obsolete and we knew we could be without OES in the event of a breakdown.
Russell Northey, Metallurgist, CAA
The use of OES is commonplace in “hot metal” companies, such as CAA, and provides rapid quality control of metal components. Russell is highly experienced in OES, having been involved in the installation of seven different OES instruments at different companies in the last thirty years.
The Directors of CAA were able to place their full trust in his experience and choice of new OES system. Russell was able to take some time to ‘do his homework’ and find the right instrument to satisfy the company’s requirements.
I have gained a lot of experience in OES and I generally learn a great deal from instrument manufacturers. Metallurgy and OES have a lot of cross-over and it was priceless to work with Oxford Instruments.
Russell Northey, Metallurgist, CAA
OES Technology Then and Now
OES instruments have evolved a great deal since the 1980’s. The older instruments used PMT’s (Photo-Multiplier Tube) and were generally very bulky, some required a purpose built building to house them. Modern OES instruments use CCDs (Charge Coupled Device) and generally have a much smaller footprint. As well as detectors there is also a choice of the optics themselves.
Traditional instruments tend to use vacuum optics, and others where low wavelength elements are not required use air optics. For more specialized applications Argon purged optics are also available.
After studying all the differences and learning a little more about CCD instruments and knowing the quality expected by Cathodic Anodes Australasia I had to choose the Oxford instrument.
Russell Northey, Metallurgist, CAA
Decision Factors
Calibration was one of the major factors that influenced the decision to choose an Oxford Instruments OES. Factory calibration can often be a double-edged sword; it is convenient but often new users have to purchase additional Certified Reference Materials (CRM) to satisfy their requirements.
The expense or availability of CRM’s can be a problem for smaller companies. “In our product there is very little certified material available with some of the micro-alloys we use; hence one is left to make their own.” The FOUNDRY MASTER Xpert is different as it has access to a comprehensive CRM database, which provides the ability to provide accurate analyses straight out of the box.
I was discussing factory calibration with Oxford and they invited me to send some samples to the factory giving them no clues on the composition – they would run them on an instrument straight off the line… I was overwhelmed when an E-mail came showing 12 regressions of each sample. Everything was right – To see an analytical range is one thing – to get a correct analysis is another.
Russell Northey, Metallurgist, CAA
Oxford Instruments Calibration
Oxford Instruments provide a comprehensive service to calibrate and set up the chosen instrument in the way required by the customer.
Oxford discussed commissioning with me if I were to get an instrument. All we had to do was have a sample of the material which we would normally be testing on the instrument. If buying an instrument with multiple bases, a sample from each base. The installation technician simply runs a Drift Correction and then runs the sample.
Russell Northey, Metallurgist, CAA
According to Russell the instrument installed for CAA has three bases: Aluminum, Zinc and Magnesium but is capable of handling ten bases. The Aluminum base has seven sub-programs, which are the ‘series alloys’ groups. The Al-Zn program, which accounts for the majority of Aluminum work, has 96 CRM’s that make up 55 curves to display 32 elements. There are up to 19 Aluminum reference (lines) intensities available in these CCD instruments.
For some one used to just one channel this is an amazing amount of analysis capability.
Russell Northey, Metallurgist, CAA
Vacuum Optic
Detection limits and optics are important for CCD OES. Russell purchased the Foundry Master due to its ability to display at 0.00006 above the bottom point value of a curve, and also because of the availability of extremely stable vacuum optics.
I believe the vacuum optic has not only provided rock solid stability but also delivered the superior detection limits we require in our process. This instrument pushes the boundaries of the available CRM. The vacuum optic also helps keep argon costs to a minimum. The Vacuum Optic is a good alternative to have for stability and future proofing and the instruments argon use overall is very low.
Russell Northey, Metallurgist, CAA
Automatic Profiling
The Foundry Master Xpert has an ‘automatic profile’ every burn and this is known as PPA (Peak Position Alignment). This alignment is performed for each burn integration to avoid drift. Drift correction or Recalibration is one of the most important abilities of the new Xpert, the instrument comes with a set of SUS (Set Up Standards) or Recal ‘blocks’ for each base. These blocks apply a correction factor to each curve to ensure the master calibration remains constant.
The instrument can also do a ‘global’ Recal, where several different alloys are constantly analyzed, or a partial Recal, where the same alloy is analyzed day in day out. The software also has a ability to use a new set of blocks in the future, but maintain the initial factory calibration. The software also has the ability to create an entire new analytical program using additional standards. The Xpert can also carry out ‘Type Correction’ as a minor every day correction using Recal blocks to assess if drift correction is required.
Orientation scans are an excellent feature of the Xpert and for some bases such as iron and aluminum there are sub-programs, which can be used if there is uncertainty about the program to use. The orientation process uses a series of simple scans, and the instrument (software) will decide which program (set of curves) is best for the ‘unknown or unexpected sample’. This is particularly good for copper base alloy systems.
The Xpert proves that small footprint CCD instruments have the quality to provide excellent results. There is no compromise – the Xpert is believed to have the widest spectral range of ‘benchtop’ instruments - from 130 to 750 nm.
Easy Reports
The software is based on Windows 7 and provides a great many important functions:
- There is an A4 ‘document’ that can be customized – you can add company logo’s, letterheads, as well as ‘splash’ the analysis results, average, specifications and any or all of 20 available data fields.
- The software has an internal database to recall stored analysis.
- Data files can be used to report large groups of analysis - it stores all 20 data fields, date, time, program, grade check, and most important the results.
- A copy of the calibration unique to every instrument is held by Oxford Instruments, and a USB stick with them on is included.
Low Maintenance
Maintenance is minimal and argon use is very low. The vacuum optic has a ball valve on both the lens side, and at the rear on the pump side. The system can be isolated to hold vacuum whilst the lens is cleaned. Spark stand maintenance is simple and well documented in the manual. The software has a counter with a pop up as a reminder to clean the stand. The electrodes can be changed without opening the stand, as it is necessary to change electrodes when changing bases, for the PPA to work effectively.
Conclusion
The Foundry Master Xpert is a superlative instrument with a number of innovative features to save both time and money in OES analysis.
I have no hesitation in recommending these instruments to any manufacturer looking to secure their future. Oxford Instruments have produced a masterpiece.
Russell Northey, Metallurgist, CAA
This information has been sourced, reviewed and adapted from materials provided by Oxford Instruments.
For more information on this source, please visit Oxford Instruments.